Merge pull request #1735 from bilawalsidhu/manjunath/rail-panels

Side rails: Visual on the left rail, edge mode and edge scrolling

changelog.d/1735-side-rails-edge.md

@@ -0,0 +1,5 @@
+- Move Visual to the left rail, after Data Layers, Utilities and Authoring, and
+  lead the right column with Context; an open Context or CCTV panel takes the
+  column's full height. A switch in each panel header moves that side's panels
+  over their rail to the screen edge, and the scroll wheel at a screen edge
+  steps through that side's panels (manjunath22466, samehkhamis, #1735).

docs/CURRENT-STATE.md

@@ -627,6 +627,36 @@ panel that holds its row, and `set_panel_open` reaches it as
 `utilities-panel` or by "utilities", "draw", "drawing" or "import". On a phone
 it sits collapsed in the Layers sheet under Data Layers.
 
+## Side rails and the screen edge — November 14, 2026
+
+Visual (`#pp-toggles`, the display settings, rail item `palette`) is the last
+panel of the left column, after Data Layers, Utilities and Authoring, and
+opens from the left rail like them (`PanelLayoutController`, falling back to
+the right column in a host without a left stack). Context leads the right
+column, followed by CCTV, Street Level and the other right panels. An open
+Context or CCTV panel takes the column's full height; the other right panels
+keep the content-sized layout and its hysteresis band. With nothing open, a
+rail's icons and their names show as two glass pieces side by side; once a
+panel opens, the icons stay in place and a highlight slides to the open one.
+
+Each collapsible panel header has an edge switch (`UiPanelEdge.vue`,
+`src/ui/panelEdge.js`): it moves that side's panels over their rail to the
+screen edge, with the rail as a row of icons above the open panel, and back.
+The choice is per side, kept in `localStorage` (`gev.panelEdge`), and applies
+on the desktop shell only: phones and Cockpit keep their own layouts and do
+not show the switch.
+
+Scrolling the wheel at a screen edge (`src/ui/railEdgeScroll.js`, from the
+edge to just past the rail, at most 84 px) steps that side's rail to its next
+or previous panel instead of zooming the globe, wrapping round at either end.
+One gesture is one step, trackpad coasting included, with at least half a
+second between steps; a step that comes too soon is held until then and is
+dropped if the pointer leaves the strip. Panels, controls, dialogs and the
+world timeline in the strip keep their own wheel. The strip is off on phones
+and touch screens, while the rails are hidden (clean view, recording), and it
+follows the rails' sides in a right-to-left language. On a phone, Visual is in
+the More sheet with the dock's Visual Presets, as before.
+
 ## God's Eye View in conversations — October 2, 2026
 
 Tool answers that can be shown in God's Eye View include a view: camera, layers,

index.html

@@ -26,7 +26,7 @@
        with the sources: src/materialSymbolsSubset.test.mjs fails when a source
        names a glyph this list is missing, because a missing glyph does not draw
        a box — the ligature never forms and the element renders the literal word. -->
-  <link href="https://fonts.googleapis.com/css2?family=Material+Symbols+Outlined:opsz,wght,FILL,GRAD@20,400,0,0&icon_names=adjust,arrow_drop_down,arrow_forward,arrow_left,arrow_right,bolt,bug_report,category,chevron_left,chevron_right,close,close_fullscreen,dark_mode,delete,directions_boat,draw,east,eco,egg_alt,flare,flight,handyman,layers,layers_clear,light_mode,local_fire_department,location_on,more_horiz,movie,my_location,navigation,normal,on,open_in_full,partly_cloudy_day,pause,pentagon,pest_control,pets,play_arrow,public,question_mark,radar,radio,raven,right_panel_close,right_panel_open,rocket_launch,satellite_alt,search,set_meal,settings,skip_next,skip_previous,streetview,timeline,traffic,tune,umbrella,upload_file,videocam,view_in_ar,visibility,visibility_off,water_drop,zoom_in_map" rel="stylesheet" />
+  <link href="https://fonts.googleapis.com/css2?family=Material+Symbols+Outlined:opsz,wght,FILL,GRAD@20,400,0,0&icon_names=adjust,align_horizontal_left,align_horizontal_right,arrow_drop_down,arrow_forward,arrow_left,arrow_right,bolt,bug_report,category,chevron_left,chevron_right,close,close_fullscreen,dark_mode,delete,directions_boat,draw,east,eco,egg_alt,flare,flight,handyman,layers,layers_clear,light_mode,local_fire_department,location_on,more_horiz,movie,my_location,navigation,normal,on,open_in_full,palette,partly_cloudy_day,pause,pentagon,pest_control,pets,play_arrow,public,question_mark,radar,radio,raven,right_panel_close,right_panel_open,rocket_launch,satellite_alt,search,set_meal,settings,skip_next,skip_previous,streetview,timeline,traffic,tune,umbrella,upload_file,videocam,view_in_ar,visibility,visibility_off,water_drop,zoom_in_map" rel="stylesheet" />
 </head>
 <body>
   <div class="gev-view" data-gev-view="scene-chrome"></div>

scripts/format-scope.json

@@ -1449,5 +1449,13 @@
   "src/data/fleetModelInstances.test.mjs",
   "src/testSupport/fleetGlb.mjs",
   "src/testSupport/fleetModelFakes.mjs",
-  "scripts/measure-fleet-trail-anchors.mjs"
+  "scripts/measure-fleet-trail-anchors.mjs",
+  "src/ui/panelEdge.js",
+  "src/ui/railEdgeScroll.js",
+  "src/ui/railEdgeScroll.test.mjs",
+  "src/ui/kit/UiPanelEdge.vue",
+  "src/ui/styles/rail-edge.css",
+  "src/ui/styles/rail-split.css",
+  "src/ui/styles/left-tools.css",
+  "src/ui/styles/panel-edge.css"
 ]

scripts/package-boundaries.json

@@ -154,6 +154,8 @@
       "src/ui/kit/UiSegmented.vue",
       "src/ui/rail/RailPanel.vue",
       "src/ui/kit/UiPanel.vue",
+      "src/ui/kit/UiPanelEdge.vue",
+      "src/ui/panelEdge.js",
       "src/ui/kit/UiPanelToggle.vue",
       "src/ui/stores/panelChrome.js",
       "src/ui/rail/PanelCollapseButton.vue",
@@ -1136,6 +1138,7 @@
       "src/styles/surveillance.js",
       "src/styles/thermal.js",
       "src/ui/applicationShell.js",
+      "src/ui/railEdgeScroll.js",
       "src/ui/localePicker.js",
       "src/ui/cyberSonarControls.js",
       "src/ui/locationNavigation.js",
@@ -3087,6 +3090,7 @@
       "src/styles/surveillance.js",
       "src/styles/thermal.js",
       "src/ui/applicationShell.js",
+      "src/ui/railEdgeScroll.js",
       "src/ui/mobileShell.js",
       "src/exclusiveSurfaces.js",
       "src/ui/localePicker.js",

src/contextTabKeyboard.test.mjs

@@ -4,18 +4,31 @@ import { _selectContextMode } from './ui/contextTransactions.js';
 import { _initGlobalContextPanel } from './ui/contextBindings.js';
 import { clearSelectedLayers } from './ui/contextActions.js';
 import { readFileSync as readRadioSource } from 'node:fs';
-const radioBindings = readRadioSource(new URL('./ui/radioBindings.js', import.meta.url), 'utf8');
+const radioBindings = readRadioSource(
-const contextView = readRadioSource(new URL('./ui/views/ContextView.vue', import.meta.url), 'utf8');
+  new URL('./ui/radioBindings.js', import.meta.url),
+  'utf8',
+);
+const contextView = readRadioSource(
+  new URL('./ui/views/ContextView.vue', import.meta.url),
+  'utf8',
+);
 import { readFileSync } from 'node:fs';
 import { test } from 'node:test';
 import assert from 'node:assert/strict';
 
-const html = await renderApplicationHtml(readFileSync(new URL('../index.html', import.meta.url), 'utf8'));
+const html = await renderApplicationHtml(
+  readFileSync(new URL('../index.html', import.meta.url), 'utf8'),
+);
 const css = readStylesheet(new URL('../style.css', import.meta.url));
 
 test('Contacts and Space Missions both participate in the ordinary Tab sequence', () => {
-  for (const id of ['global-context-flights-btn', 'global-context-missions-btn']) {
+  for (const id of [
-    const button = html.match(new RegExp(`<button id="${id}"[\\s\\S]*?</button>`));
+    'global-context-flights-btn',
+    'global-context-missions-btn',
+  ]) {
+    const button = html.match(
+      new RegExp(`<button id="${id}"[\\s\\S]*?</button>`),
+    );
     assert.ok(button, `${id} is missing`);
     assert.match(button[0], /role="tab"/);
     assert.match(button[0], /tabindex="0"/);
@@ -23,7 +36,10 @@ test('Contacts and Space Missions both participate in the ordinary Tab sequence'
 
   // The view keeps both tabs' tabindex static and never disables them; the
   // transition itself is covered over happy-dom in ui/contextPanel.test.mjs.
-  for (const id of ['global-context-flights-btn', 'global-context-missions-btn']) {
+  for (const id of [
+    'global-context-flights-btn',
+    'global-context-missions-btn',
+  ]) {
     const tag = contextView.match(new RegExp(`<button id="${id}"[^>]*>`))?.[0];
     assert.ok(tag, `${id} is missing from the view`);
     assert.doesNotMatch(tag, /:tabindex|:disabled|\sdisabled/);
@@ -34,9 +50,22 @@ test('Context activation and Clear All never native-disable tabs and guard repea
   const init = _initGlobalContextPanel.toString();
   const select = _selectContextMode.toString();
   const clear = clearSelectedLayers.toString();
-  assert.equal((init.match(/if \(\s*this\.destroyed\s*\|\|\s*this\._contextModeChanging\s*\|\|\s*this\._clearSelectedLayersPromise\s*\)\s*return;/g) || []).length, 2);
+  assert.equal(
-  assert.doesNotMatch(select, /_globalContext(?:Flights|Missions)Btn\.disabled\s*=\s*true/);
+    (
-  assert.doesNotMatch(clear, /_globalContext(?:Flights|Missions)Btn\.disabled\s*=\s*true/);
+      init.match(
+        /if \(\s*this\.destroyed\s*\|\|\s*this\._contextModeChanging\s*\|\|\s*this\._clearSelectedLayersPromise\s*\)\s*return;/g,
+      ) || []
+    ).length,
+    2,
+  );
+  assert.doesNotMatch(
+    select,
+    /_globalContext(?:Flights|Missions)Btn\.disabled\s*=\s*true/,
+  );
+  assert.doesNotMatch(
+    clear,
+    /_globalContext(?:Flights|Missions)Btn\.disabled\s*=\s*true/,
+  );
 });
 
 test('Context tablist retains Left, Right, Home, and End keyboard navigation', () => {
@@ -45,40 +74,62 @@ test('Context tablist retains Left, Right, Home, and End keyboard navigation', (
   assert.match(initSource, /event\.key === 'ArrowLeft'/);
   assert.match(initSource, /event\.key === 'Home'/);
   assert.match(initSource, /event\.key === 'End'/);
-  assert.match(initSource, /contextTabs\[nextIndex\]\.focus\(\{ preventScroll: true \}\)/);
+  assert.match(
+    initSource,
+    /contextTabs\[nextIndex\]\.focus\(\{ preventScroll: true \}\)/,
+  );
   assert.match(initSource, /contextTabs\[nextIndex\]\.click\(\)/);
 });
 
 test('Context tabs draw a visible keyboard-focus outline including active tabs', () => {
   const rules = [...css.matchAll(/([^{}]+)\{([^{}]*)\}/g)];
-  const focusRule = rules.find(([, selector, body]) => (
+  const focusRule = rules.find(
-    selector.trim().endsWith('.context-mode-button:focus-visible')
+    ([, selector, body]) =>
-      && /outline:\s*2px solid var\(--text-primary\)/.test(body)
+      selector.trim().endsWith('.context-mode-button:focus-visible') &&
-  ));
+      /outline:\s*2px solid var\(--text-primary\)/.test(body),
-  assert.ok(focusRule, 'Context focus-visible rule must draw a two-pixel outline');
+  );
+  assert.ok(
+    focusRule,
+    'Context focus-visible rule must draw a two-pixel outline',
+  );
   assert.match(focusRule[2], /outline-offset:\s*-3px/);
 
-  const activeRule = rules.find(([, selector]) => selector.trim().endsWith('.context-mode-button.active'));
+  const activeRule = rules.find(([, selector]) =>
+    selector.trim().endsWith('.context-mode-button.active'),
+  );
   assert.ok(activeRule, 'Context active-state rule is missing');
   assert.doesNotMatch(activeRule[2], /outline:\s*none/);
 });
 
 test('Context async action buttons remain focused while busy', () => {
   const init = _initGlobalContextPanel.toString();
-  const radio = radioBindings.slice(radioBindings.indexOf('const toggleRadio = async (trigger) => {'), radioBindings.indexOf('this._storeToken = this.store?.connect?.('));
+  const radio = radioBindings.slice(
-  const radioPanel = readFileSync(new URL('./ui/views/panels/RadioPanel.vue', import.meta.url), 'utf8');
+    radioBindings.indexOf('const toggleRadio = async (trigger) => {'),
+    radioBindings.indexOf('this._storeToken = this.store?.connect?.('),
+  );
+  const radioPanel = readFileSync(
+    new URL('./ui/views/panels/RadioPanel.vue', import.meta.url),
+    'utf8',
+  );
   const clear = clearSelectedLayers.toString();
 
   assert.match(init, /if \(this\._installationsSearchBusy\) return;/);
   assert.doesNotMatch(init, /\.disabled\s*=\s*true/);
-  const search = contextView.match(/<button id="installations-search-btn"[^>]*>/)?.[0];
+  const search = contextView.match(
+    /<button id="installations-search-btn"[^>]*>/,
+  )?.[0];
   assert.ok(search, 'nearby sites search is missing');
   assert.doesNotMatch(search, /:disabled|\sdisabled/);
   assert.match(search, /:aria-busy=/);
   assert.match(radio, /trigger\.getAttribute\('aria-busy'\) === 'true'/);
   assert.doesNotMatch(radio, /trigger\.disabled\s*=\s*true/);
-  const cockpitRadio = readFileSync(new URL('./ui/views/panels/CockpitUtilityControls.vue', import.meta.url), 'utf8');
+  const cockpitRadio = readFileSync(
-  const cockpitEnable = cockpitRadio.match(/<UiButton id="cockpit-radio-enable-btn"[^>]*>/)?.[0];
+    new URL('./ui/views/panels/CockpitUtilityControls.vue', import.meta.url),
+    'utf8',
+  );
+  const cockpitEnable = cockpitRadio.match(
+    /<UiButton id="cockpit-radio-enable-btn"[^>]*>/,
+  )?.[0];
   assert.ok(cockpitEnable, 'Cockpit Radio Enable button is missing');
   assert.doesNotMatch(cockpitEnable, /disabled(?!=")|:disabled/);
   assert.match(cockpitEnable, /:aria-busy=/);
@@ -89,44 +140,84 @@ test('Context async action buttons remain focused while busy', () => {
   assert.match(enable, /:aria-busy=/);
   assert.match(clear, /this\.setClearBusy\(true\)/);
   // The globe actions view marks the clear button busy, never disabled.
-  const globeActions = readFileSync(new URL('./ui/views/panels/GlobeActions.vue', import.meta.url), 'utf8');
+  const globeActions = readFileSync(
-  const clearButton = globeActions.match(/<button id="clear-selected-layers"[^>]*>/)?.[0];
+    new URL('./ui/views/panels/GlobeActions.vue', import.meta.url),
+    'utf8',
+  );
+  const clearButton = globeActions.match(
+    /<button id="clear-selected-layers"[^>]*>/,
+  )?.[0];
   assert.ok(clearButton, 'Clear selected layers button is missing');
   assert.doesNotMatch(clearButton, /disabled(?!=")|:disabled=/);
   assert.match(clearButton, /:aria-busy=/);
 });
 
-test('Context header holds only its title and collapse control', () => {
+test('Context header holds only its title, edge switch and collapse control', () => {
-  const panel = html.match(/<div id="global-context-panel"[\s\S]*?<div class="cyber-panel-body[ "]/);
+  const panel = html.match(
+    /<div id="global-context-panel"[\s\S]*?<div class="cyber-panel-body[ "]/,
+  );
   assert.ok(panel, 'Global Context panel is missing');
-  const header = panel[0].match(/<div class="ui-panel__head panel-header">([\s\S]*?)<\/div>\s*<div class="cyber-panel-body[ "]/);
+  const header = panel[0].match(
+    /<div class="ui-panel__head panel-header">([\s\S]*?)<\/div>\s*<div class="cyber-panel-body[ "]/,
+  );
   assert.ok(header, 'Global Context header is missing');
   // The kit's own ui-* classes carry no Core styles.
-  const tags = [...header[1].matchAll(/<(\w+)\s+(?:type="button"\s+)?class="([^"]+)"/g)].map(([, tag, cls]) =>
+  const tags = [
-    `${tag}.${cls.split(' ').filter((name) => !/^ui-/.test(name)).join(' ')}`);
+    ...header[1].matchAll(/<(\w+)\s+(?:type="button"\s+)?class="([^"]+)"/g),
-  assert.deepEqual(tags, ['span.panel-title', 'span.panel-divider', 'button.panel-collapse-btn']);
+  ].map(
+    ([, tag, cls]) =>
+      `${tag}.${cls
+        .split(' ')
+        .filter((name) => !/^ui-/.test(name))
+        .join(' ')}`,
+  );
+  assert.deepEqual(tags, [
+    'span.panel-title',
+    'span.panel-divider',
+    'button.panel-edge-btn',
+    'span.material-symbols-outlined',
+    'button.panel-collapse-btn',
+  ]);
 });
 
 test('Context reads as one segmented control with legible type and no halo', () => {
   const rules = [...css.matchAll(/([^{}]+)\{([^{}]*)\}/g)];
-  const clean = (selector) => selector.replace(/\/\*[\s\S]*?\*\//g, '').replace(/\s+/g, ' ').trim();
+  const clean = (selector) =>
-  const rule = (selector) => rules.find(([, s]) => clean(s) === selector)?.[2] || '';
+    selector
-  const px = (body, prop) => Number(body.match(new RegExp(`${prop}:[^;]*?(\\d+(?:\\.\\d+)?)px`))?.[1] || 0);
+      .replace(/\/\*[\s\S]*?\*\//g, '')
+      .replace(/\s+/g, ' ')
+      .trim();
+  const rule = (selector) =>
+    rules.find(([, s]) => clean(s) === selector)?.[2] || '';
+  const px = (body, prop) =>
+    Number(
+      body.match(new RegExp(`${prop}:[^;]*?(\\d+(?:\\.\\d+)?)px`))?.[1] || 0,
+    );
 
   assert.match(rule('#global-context-panel .panel-glow'), /display:\s*none/);
   const modes = rule('.global-context-modes');
   assert.match(modes, /border:\s*1px solid/);
   assert.match(modes, /padding:\s*2px/);
-  assert.ok(px(rule('.context-mode-button'), 'font') >= 10, 'mode labels must stay at least 10px');
+  assert.ok(
+    px(rule('.context-mode-button'), 'font') >= 10,
+    'mode labels must stay at least 10px',
+  );
   assert.doesNotMatch(rule('.context-mode-button.active'), /box-shadow/);
   const standby = rule('.context-mode-standby');
-  assert.ok(px(standby, 'font') >= 10, 'standby guidance must stay at least 10px');
+  assert.ok(
+    px(standby, 'font') >= 10,
+    'standby guidance must stay at least 10px',
+  );
   assert.doesNotMatch(standby, /dashed/);
-  assert.ok(px(rule('.global-context-actions .panel-layer-toggle'), 'font-size') >= 10);
+  assert.ok(
+    px(rule('.global-context-actions .panel-layer-toggle'), 'font-size') >= 10,
+  );
   // The shared rail title colour (brighter than --text-secondary) keeps the
   // open Context title legible; no Context-only rule dims it again.
   assert.equal(
-    rule(":root:not([data-ui-theme='cyber']) #global-context-panel:not(.collapsed) .panel-title"),
+    rule(
+      ":root:not([data-ui-theme='cyber']) #global-context-panel:not(.collapsed) .panel-title",
+    ),
     '',
   );
 });

src/i18n/locales/ar.json

@@ -3967,5 +3967,7 @@
   "Cable car": "ترام كابلي",
   "Monorail": "قطار أحادي السكة",
   "Funicular": "قطار جبلي مائل",
-  "Gondola": "تلفريك"
+  "Gondola": "تلفريك",
+  "Move panels back beside the rail": "إعادة اللوحات إلى جانب الشريط",
+  "Move panels over the rail, to the edge": "نقل اللوحات فوق الشريط إلى الحافة"
 }

src/i18n/locales/de.json

@@ -3619,5 +3619,7 @@
   "Cable car": "Kabelstraßenbahn",
   "Monorail": "Einschienenbahn",
   "Funicular": "Standseilbahn",
-  "Gondola": "Gondelbahn"
+  "Gondola": "Gondelbahn",
+  "Move panels back beside the rail": "Bedienfelder zurück neben die Leiste",
+  "Move panels over the rail, to the edge": "Bedienfelder über die Leiste an den Rand verschieben"
 }

src/i18n/locales/es.json

@@ -3706,5 +3706,7 @@
   "Cable car": "Tranvía de cable",
   "Monorail": "Monorraíl",
   "Funicular": "Funicular",
-  "Gondola": "Góndola"
+  "Gondola": "Góndola",
+  "Move panels back beside the rail": "Devolver los paneles junto a la barra",
+  "Move panels over the rail, to the edge": "Mover los paneles sobre la barra, hasta el borde"
 }

src/i18n/locales/fr.json

@@ -3706,5 +3706,7 @@
   "Cable car": "Tramway à câble",
   "Monorail": "Monorail",
   "Funicular": "Funiculaire",
-  "Gondola": "Télécabine"
+  "Gondola": "Télécabine",
+  "Move panels back beside the rail": "Remettre les panneaux à côté de la barre",
+  "Move panels over the rail, to the edge": "Déplacer les panneaux par-dessus la barre, jusqu’au bord"
 }

src/i18n/locales/he.json

@@ -3706,5 +3706,7 @@
   "Cable car": "חשמלית כבלים",
   "Monorail": "מונורייל",
   "Funicular": "פוניקולר",
-  "Gondola": "רכבל"
+  "Gondola": "רכבל",
+  "Move panels back beside the rail": "החזרת הלוחות לצד הסרגל",
+  "Move panels over the rail, to the edge": "הזזת הלוחות מעל הסרגל, אל הקצה"
 }

src/i18n/locales/it.json

@@ -3706,5 +3706,7 @@
   "Cable car": "Tram a fune",
   "Monorail": "Monorotaia",
   "Funicular": "Funicolare",
-  "Gondola": "Cabinovia"
+  "Gondola": "Cabinovia",
+  "Move panels back beside the rail": "Riporta i pannelli accanto alla barra",
+  "Move panels over the rail, to the edge": "Sposta i pannelli sopra la barra, fino al bordo"
 }

src/i18n/locales/ja.json

@@ -3532,5 +3532,7 @@
   "Cable car": "ケーブルトラム",
   "Monorail": "モノレール",
   "Funicular": "ケーブルカー",
-  "Gondola": "ゴンドラ"
+  "Gondola": "ゴンドラ",
+  "Move panels back beside the rail": "パネルをレールの横に戻す",
+  "Move panels over the rail, to the edge": "パネルをレールの上、画面端へ移動"
 }

src/i18n/locales/pt.json

@@ -3706,5 +3706,7 @@
   "Cable car": "Bonde a cabo",
   "Monorail": "Monotrilho",
   "Funicular": "Funicular",
-  "Gondola": "Teleférico"
+  "Gondola": "Teleférico",
+  "Move panels back beside the rail": "Voltar os painéis para junto da barra",
+  "Move panels over the rail, to the edge": "Mover os painéis sobre a barra, até a borda"
 }

src/i18n/locales/ru.json

@@ -3793,5 +3793,7 @@
   "Cable car": "Канатный трамвай",
   "Monorail": "Монорельс",
   "Funicular": "Фуникулёр",
-  "Gondola": "Канатная дорога"
+  "Gondola": "Канатная дорога",
+  "Move panels back beside the rail": "Вернуть панели к боковой панели",
+  "Move panels over the rail, to the edge": "Переместить панели поверх боковой панели к краю"
 }

src/i18n/locales/sv.json

@@ -3619,5 +3619,7 @@
   "Cable car": "Kabelspårvagn",
   "Monorail": "Enskensbana",
   "Funicular": "Bergbana",
-  "Gondola": "Kabinbana"
+  "Gondola": "Kabinbana",
+  "Move panels back beside the rail": "Flytta tillbaka panelerna bredvid listen",
+  "Move panels over the rail, to the edge": "Flytta panelerna över listen, till kanten"
 }

src/i18n/locales/uk.json

@@ -3793,5 +3793,7 @@
   "Cable car": "Канатний трамвай",
   "Monorail": "Монорейка",
   "Funicular": "Фунікулер",
-  "Gondola": "Канатна дорога"
+  "Gondola": "Канатна дорога",
+  "Move panels back beside the rail": "Повернути панелі до бічної смуги",
+  "Move panels over the rail, to the edge": "Перемістити панелі поверх бічної смуги до краю"
 }

src/i18n/locales/zh-CN.json

@@ -3532,5 +3532,7 @@
   "Cable car": "缆索电车",
   "Monorail": "单轨列车",
   "Funicular": "缆索铁路",
-  "Gondola": "缆车"
+  "Gondola": "缆车",
+  "Move panels back beside the rail": "将面板移回侧栏旁",
+  "Move panels over the rail, to the edge": "将面板移到侧栏上方，贴靠边缘"
 }

src/i18n/locales/zh-Hant.json

@@ -3532,5 +3532,7 @@
   "Cable car": "纜索電車",
   "Monorail": "單軌列車",
   "Funicular": "纜索鐵路",
-  "Gondola": "纜車"
+  "Gondola": "纜車",
+  "Move panels back beside the rail": "將面板移回側欄旁",
+  "Move panels over the rail, to the edge": "將面板移到側欄上方，貼齊邊緣"
 }

src/ui/applicationShell.js

@@ -65,6 +65,7 @@ import { useHudStore } from './stores/hud.js';
 import { useDisplayStore } from './stores/display.js';
 import { useLocaleStore } from './stores/locale.js';
 import { useLocationStore } from './stores/location.js';
+import { installRailEdgeScroll } from './railEdgeScroll.js';
 import { useCockpitStore } from './stores/cockpit.js';
 import { useGlobeActionsStore } from './stores/globeActions.js';
 import { useRecordingStore } from './stores/recording.js';
@@ -164,6 +165,8 @@ export class StyleManager extends ShellFacade {
     });
     // Vue views share this runtime and its stores; dispose unmounts them.
     this._ui = createUiRuntime({ pinia: applicationPinia() });
+    // Scrolling at a screen edge steps through that side's rail panels.
+    this._removeRailEdgeScroll = installRailEdgeScroll();
     this._feedback = new ShellFeedback({
       readLayers: () => withPlacePacks(this._dataManager?.getAll?.() || []),
     });
@@ -1856,6 +1859,7 @@ export class StyleManager extends ShellFacade {
     const { destroyTrackedReadout, destroyWorldOverlay, destroyDetection } =
       this.services;
     if (this._disposed) return;
+    this._removeRailEdgeScroll?.();
     this._shareRestoration.destroy();
     this._feedback.clearLoadingStatus();
     this._disposed = true;

src/ui/kit/UiPanel.vue

@@ -1,5 +1,6 @@
 <script setup>
 import { vClassToggle } from '../rail/classToggle.js';
+import UiPanelEdge from './UiPanelEdge.vue';
 import UiPanelToggle from './UiPanelToggle.vue';
 
 // Core's panel, with a name, title, slots and v-model:collapsed. It draws Core's panel markup
@@ -57,6 +58,7 @@ const emit = defineEmits(['update:collapsed']);
         <slot name="badge" />
         <span class="panel-divider"></span>
         <slot name="actions" />
+        <UiPanelEdge v-if="props.collapsible" />
         <UiPanelToggle
           v-if="props.collapsible"
           :target="props.id"

src/ui/kit/UiPanelEdge.vue

@@ -0,0 +1,48 @@
+<script setup>
+import { computed, onMounted, ref } from 'vue';
+import { t } from '../../i18n/index.js';
+import { panelEdge, panelSide, togglePanelEdge } from '../panelEdge.js';
+
+// A panel header's edge switch: it slides this side's panels over their rail
+// to the screen edge, and back. The side comes from the column the panel is in.
+const button = ref(null);
+const side = ref('left');
+const on = computed(() => panelEdge.value[side.value]);
+function toggle() {
+  side.value = panelSide(button.value);
+  togglePanelEdge(side.value);
+}
+function sync() {
+  side.value = panelSide(button.value);
+}
+// The layout moves some panels to the right column after they mount, so the
+// side is read again once that has happened.
+onMounted(() => {
+  sync();
+  globalThis.requestAnimationFrame?.(sync);
+});
+const icon = computed(() =>
+  side.value === 'right' ? 'align_horizontal_right' : 'align_horizontal_left',
+);
+const label = computed(() =>
+  on.value
+    ? t('Move panels back beside the rail')
+    : t('Move panels over the rail, to the edge'),
+);
+</script>
+
+<template>
+  <button
+    ref="button"
+    type="button"
+    class="ui-panel-edge panel-edge-btn"
+    :aria-pressed="String(on)"
+    :aria-label="label"
+    :title="label"
+    @pointerenter="sync"
+    @focus="sync"
+    @click="toggle"
+  >
+    <span class="material-symbols-outlined" aria-hidden="true">{{ icon }}</span>
+  </button>
+</template>

src/ui/leftPanelRail.js

@@ -60,6 +60,7 @@ export function layoutLeftPanelRail({
     stack.style.removeProperty('--left-stack-safe-bottom');
     stack.style.removeProperty('--left-stack-centered-height');
     stack.style.removeProperty('--panel-rail-offset');
+    stack.style.removeProperty('--panel-rail-lift');
     stack.classList.remove('layout-exclusive');
     stack.dataset.layoutMode = 'mobile';
     settleSideAccordion({ panels, enabled: false, onCollapse });
@@ -282,10 +283,19 @@ export function layoutLeftPanelRail({
     getComputedStyle(stack)
       .getPropertyValue?.('--panel-stack-top-pinned')
       ?.trim() === '1';
-  const railOffset = `${(topPinned ? 0 : safeTop - layoutTop).toFixed(1)}px`;
+  // The stack itself rises by the lift below, by a different amount for a
+  // tall panel than at rest; the rail takes up the difference.
+  const lift = (top) => Math.min(0, obstacleSafeTop - top);
+  const railOffset = `${(topPinned ? 0 : safeTop + lift(safeTop) - layoutTop - lift(layoutTop)).toFixed(1)}px`;
   if (stack.style.getPropertyValue('--panel-rail-offset') !== railOffset) {
     stack.style.setProperty('--panel-rail-offset', railOffset);
   }
+  // How far the column can rise before it meets the HUD readout, so the rail
+  // and any open panel sit just under it, whether or not a panel is open.
+  const railLift = `${(topPinned ? 0 : lift(layoutTop)).toFixed(1)}px`;
+  if (stack.style.getPropertyValue('--panel-rail-lift') !== railLift) {
+    stack.style.setProperty('--panel-rail-lift', railLift);
+  }
   stack.style.removeProperty('--left-stack-centered-height');
   for (const panel of panels)
     panel.style.removeProperty('--left-panel-allocated-height');

src/ui/mobileShell.js

@@ -368,7 +368,8 @@ export function initMobileShell({
         : sheet === 'search'
           ? [dock]
           : sheet === 'more'
-            ? [element('right-context-rail'), dock]
+            ? // Visual lives in the left stack; the dock holds the presets.
+              [element('left-panel-stack'), dock]
             : [element('right-context-rail')];
     return roots.find((root) => root?.contains(target));
   };

src/ui/mobileShell.test.mjs

@@ -623,7 +623,7 @@ test('the phone shell keeps the required attribution visible', () => {
   );
   const openDock = rule('body.mobile-shell[data-mobile-sheet] #command-dock');
   const railSheet = rule(
-    "body.mobile-shell[data-mobile-sheet='more'] #right-context-rail",
+    "body.mobile-shell[data-mobile-sheet='more'] #left-panel-stack",
   );
   assert.ok(z(sheetCredit) > z(openDock));
   assert.ok(z(sheetCredit) > z(railSheet));

src/ui/panelChromeButtons.test.mjs

@@ -141,6 +141,7 @@ test("UiPanel draws Core's panel markup and asks for the other state", async (t)
       'demo-badge',
       'panel-divider',
       'demo-action',
+      'panel-edge-btn',
       'panel-collapse-btn',
     ],
   );

src/ui/panelEdge.js

@@ -0,0 +1,42 @@
+import { ref } from 'vue';
+
+// Panels can slide over their rail to the screen edge, one setting per side:
+// the left column moves onto the left rail, the right column onto the right
+// rail. Each panel header has the switch (UiPanelEdge); the choice is kept
+// for the next visit and shows as a body class the stylesheet reads.
+const KEY = 'gev.panelEdge';
+function read() {
+  try {
+    const saved = JSON.parse(globalThis.localStorage?.getItem(KEY) || '{}');
+    return { left: saved.left === true, right: saved.right === true };
+  } catch {
+    return { left: false, right: false };
+  }
+}
+
+export const panelEdge = ref(read());
+
+function apply() {
+  const body = globalThis.document?.body;
+  if (!body) return;
+  body.classList.toggle('panels-edge-left', panelEdge.value.left);
+  body.classList.toggle('panels-edge-right', panelEdge.value.right);
+}
+apply();
+
+/** Which side a panel element sits on, from the column it is in. */
+export function panelSide(element) {
+  return element?.closest?.('#right-context-rail, #cockpit-utility-controls')
+    ? 'right'
+    : 'left';
+}
+
+export function togglePanelEdge(side) {
+  panelEdge.value = { ...panelEdge.value, [side]: !panelEdge.value[side] };
+  try {
+    globalThis.localStorage?.setItem(KEY, JSON.stringify(panelEdge.value));
+  } catch {
+    // Without storage the choice lasts for this visit.
+  }
+  apply();
+}

src/ui/panelLayoutController.js

@@ -189,7 +189,11 @@ export class PanelLayoutController {
     const stack = this._rightPanelStack;
     if (!stack || !this._ppToggles) return;
 
-    stack.prepend(this._ppToggles);
+    // Visual (presets and display settings) is the last panel of the left
+    // column, after the other tools, and opens from the left rail like them.
+    if (typeof this._leftPanelStack?.append === 'function')
+      this._leftPanelStack.append(this._ppToggles);
+    else stack.prepend(this._ppToggles);
     const globalContextPanel = document.getElementById('global-context-panel');
     for (const panel of [
       this._cctvPanel,
@@ -201,6 +205,9 @@ export class PanelLayoutController {
       if (!panel) continue;
       stack.insertBefore(panel, globalContextPanel);
     }
+    // Context leads the right column: it is the panel for whatever is picked,
+    // and the camera panels follow it.
+    if (globalContextPanel) stack.prepend(globalContextPanel);
     if (typeof ResizeObserver !== 'undefined') {
       this._rightStackResizeObserver = new ResizeObserver(() => {
         this._scheduleRightPanelLayout();

src/ui/panelMeasurement.js

@@ -6,9 +6,20 @@
  * @returns {number} Natural height in CSS pixels.
  */
 export function measurePanelNaturalHeight(panel, getComputedStyle) {
-  const inner = [...panel.children].find(
+  const content = [...panel.children].filter(
     (child) => !child.classList.contains('panel-glow'),
   );
+  // A panel built as a header row and a body (Visual) scrolls as a whole, so
+  // its full scroll height is its natural height.
+  if (content.length > 1) {
+    const panelStyle = getComputedStyle(panel);
+    return Math.ceil(
+      panel.scrollHeight +
+        (parseFloat(panelStyle.borderTopWidth) || 0) +
+        (parseFloat(panelStyle.borderBottomWidth) || 0),
+    );
+  }
+  const inner = content[0];
   if (!inner)
     return Math.ceil(
       panel.scrollHeight || panel.getBoundingClientRect().height,

src/ui/panelRailCatalog.js

@@ -19,7 +19,7 @@ export const PANEL_RAIL_ITEMS = Object.freeze({
   },
   'utilities-panel': { icon: 'handyman', label: msg('UTILITIES') },
   'scene-panel': { icon: 'movie', label: msg('AUTHORING') },
-  'pp-toggles': { icon: 'tune', label: msg('DISPLAY') },
+  'pp-toggles': { icon: 'palette', label: msg('VISUAL') },
   'cctv-panel': { icon: 'videocam', label: msg('CCTV') },
   'weather-panel': { icon: 'partly_cloudy_day', label: msg('WEATHER') },
   'news-panel': { icon: 'public', label: msg('NEWS') },

src/ui/panelRails.test.mjs

@@ -359,14 +359,23 @@ test('right rail aligns to the left rail buttons while the left stack is offset'
   assert.equal(f.stack.dataset.safeTop, '286.7');
 });
 
-test('left rail buttons hold still while a tall panel moves the stack', () => {
+test('left rail buttons hold still whether the open panel is short or tall', () => {
+  // Where the rail sits: the stack's top, the stack's rise, and the rail's
+  // own offset inside the stack.
+  const railTop = (stack) =>
+    (parseFloat(stack.style.getPropertyValue('--left-stack-safe-top')) * 900) /
+      100 +
+    parseFloat(stack.style.getPropertyValue('--panel-rail-lift')) +
+    parseFloat(stack.style.getPropertyValue('--panel-rail-offset'));
+  const short = fixture('left');
+  short.expand(short.first, 250);
+  short.run();
   const f = fixture('left');
   f.expand(f.first, 900);
   f.run();
   assert.equal(f.stack.dataset.layoutMode, 'focus');
-  assert.ok(
+  assert.notEqual(short.stack.dataset.layoutMode, 'focus');
-    parseFloat(f.stack.style.getPropertyValue('--panel-rail-offset')) > 0,
+  assert.ok(Math.abs(railTop(f.stack) - railTop(short.stack)) < 0.2);
-  );
 
   // A theme that pins the stack's top (Cyber) leaves nothing to offset.
   f.stack.computed.getPropertyValue = (name) =>
@@ -447,13 +456,17 @@ test('natural height includes visible content, margins and wrapper chrome, exclu
 // Outside measurement, CCTV is 391 px in focus and 629 px in normal mode;
 // Removing only the allocation leaves focus CSS active: its next reading is
 // 422 px, so the old decision exits focus and then re-enters on the 629 px read.
-function thrashingRightRail({ focused = false, weatherOpen = false } = {}) {
+function thrashingRightRail({
+  focused = false,
+  weatherOpen = false,
+  tallId = 'cctv-panel',
+} = {}) {
   const f = fixture('right');
   f.options.windowRef.innerHeight = 920;
   f.options.leftStack.rect.top = 439.6;
   f.stack.computed.rowGap = '8px';
   const display = element('pp-toggles', { collapsed: true });
-  const cctv = element('cctv-panel', { height: 629 });
+  const cctv = element(tallId, { height: 629 });
   const weather = element('weather-panel', {
     height: 444,
     collapsed: !weatherOpen,
@@ -524,8 +537,10 @@ for (const focused of [false, true]) {
   });
 }
 
+// The hysteresis applies to panels that size to their content; CCTV and
+// Context take the column's full height whenever they are open.
 test('right rail keeps focus through 30 px content growth inside the hysteresis band', () => {
-  const f = thrashingRightRail();
+  const f = thrashingRightRail({ tallId: 'news-panel' });
   f.run();
   // Header + gap contribute 52 px: need moves 420 -> 450 -> 420.
   for (const height of [368, 398, 368, 398, 368]) {
@@ -542,7 +557,7 @@ test('right rail keeps focus through 30 px content growth inside the hysteresis
 });
 
 test('right rail enters focus only above available height and leaves below the full deadband', () => {
-  const f = thrashingRightRail();
+  const f = thrashingRightRail({ tallId: 'news-panel' });
   f.options.windowRef.innerHeight = 1000;
   f.options.leftStack.rect.top = 500;
   f.cctv.intrinsicHeight = 408; // Need equals available (460 px).
@@ -559,6 +574,16 @@ test('right rail enters focus only above available height and leaves below the f
   assert.equal(f.stack.classList.contains('layout-focus'), false);
 });
 
+test('an open CCTV panel takes the full column however short its content', () => {
+  const f = thrashingRightRail();
+  f.cctv.intrinsicHeight = 200;
+  f.run();
+  assert.equal(f.stack.classList.contains('layout-focus'), true);
+  f.cctv.classList.add('collapsed');
+  f.run();
+  assert.equal(f.stack.classList.contains('layout-focus'), false);
+});
+
 test('right rail settles a second tall panel through the accordion in one pass', () => {
   const f = thrashingRightRail({ weatherOpen: true });
   const modes = [];

src/ui/railEdgeScroll.js

@@ -0,0 +1,393 @@
+// Edge scrolling for the side rails. While the pointer is in a screen edge's
+// strip (from the edge to just past its rail), that rail's border lights up,
+// and the scroll wheel steps to the next or previous panel on that side
+// instead of zooming the globe, wrapping round at either end. The open item's
+// highlight slides between items however the panel changes, and a panel
+// opened by the wheel slides in from the direction of travel.
+
+/** How far past the rail the strip reaches, in pixels. */
+const STRIP_MARGIN = 16;
+/** Wheel travel (pixels) that counts as one step. */
+const STEP_DELTA = 40;
+/**
+ * A pause this long (ms) with no wheel events ends a scroll gesture. One
+ * gesture moves one step, however long it runs, trackpad coasting included.
+ */
+const GESTURE_GAP_MS = 180;
+/** After a step, how long (ms) before the same motion can count as a new flick. */
+const STEP_COOLDOWN_MS = 220;
+/**
+ * The least time (ms) between two steps, whatever the wheel does. A motion
+ * that would step sooner waits and steps once the gap has passed (one step
+ * held at most), so panels never switch back to back and no step is lost.
+ */
+const STEP_GAP_MS = 500;
+/** A wheel event this large (pixels) is a mouse wheel notch, not a trackpad. */
+const NOTCH_DELTA = 100;
+/** The widest the strip gets, measured from the screen edge, whatever shape the rail takes. */
+const STRIP_MAX = 84;
+/**
+ * After a step, how long (ms) the rest of that gesture is still swallowed once
+ * the pointer has left the strip, so trackpad coasting does not go on to zoom
+ * the globe. Past it, the wheel belongs to whatever is under the pointer.
+ */
+const COAST_MAX_MS = 800;
+/** Pixels per wheel line, for mice that report lines rather than pixels. */
+const LINE_PX = 16;
+/**
+ * Things in the strip that keep their own pointer and wheel behaviour: any
+ * control, and every panel in either side's stack (a panel scrolls itself).
+ */
+const OWN_CONTROLS =
+  'a, button, input, select, textarea, dialog, [role="dialog"], .ui-panel, #left-panel-stack > :not(.gev-panel-rail), #right-context-rail > :not(.gev-panel-rail), #first-run-launcher, #cesium-credits, #world-timeline';
+
+/**
+ * @param {Document} [doc]
+ * @returns {() => void} removes the listeners and observers
+ */
+export function installRailEdgeScroll(doc = globalThis.document) {
+  const win = doc?.defaultView;
+  if (!doc || !win) return () => {};
+  const coarse = win.matchMedia?.('(pointer: coarse)');
+
+  let hot = null;
+  let travel = 0;
+  let lastWheel = 0;
+  let lastSpeed = 0;
+  let stepped = false;
+  /** When the last step was taken, the fastest the gesture has been, and whether it has slowed since. */
+  let steppedAt = 0;
+  /** A step waiting for the gap to pass, if any. */
+  let heldStep = 0;
+  let peakSpeed = 0;
+  let slowed = false;
+  let frame = 0;
+  /** Set once removed, so frames already queued do nothing. */
+  let removed = false;
+
+  // Clean view and recording hide the rails with visibility and opacity,
+  // which keep their boxes, so a box alone does not mean the rail shows.
+  const showing = (node) =>
+    node.getBoundingClientRect().width > 0 &&
+    (typeof node.checkVisibility !== 'function' ||
+      node.checkVisibility({
+        visibilityProperty: true,
+        opacityProperty: true,
+      }));
+
+  // Which screen edge a rail is on comes from where it is, not its name: in a
+  // right-to-left language the left stack sits on the right.
+  const rails = () =>
+    ['left', 'right']
+      .map((name) => doc.querySelector(`.ui-rail--${name}`))
+      .filter((rail) => rail && showing(rail))
+      .map((rail) => {
+        const box = rail.getBoundingClientRect();
+        const middle = doc.documentElement.clientWidth / 2;
+        return {
+          side: box.left + box.width / 2 < middle ? 'left' : 'right',
+          rail,
+        };
+      });
+
+  const items = (rail) =>
+    // Only items that show: a theme or mode may hide some, and the wheel must
+    // not open those.
+    [...rail.querySelectorAll('.ui-rail__item')].filter(
+      (item) => !item.disabled && showing(item),
+    );
+
+  // ── The sliding highlight ──
+  // Each rail draws it as a ::before under its items, placed by custom
+  // properties; the open item's own background steps aside while it shows.
+  // Vue rewrites a rail's class list when it folds its labels, so whether the
+  // highlight is showing is kept here, and the classes are put back each time.
+  const gliding = new WeakSet();
+
+  function glide(rail) {
+    if (removed) return;
+    rail.classList.toggle('ui-rail--edge-hot', rail === hot);
+    const on = rail.querySelector('.ui-rail__item[aria-pressed="true"]');
+    if (!on?.offsetWidth) {
+      gliding.delete(rail);
+      rail.classList.remove('ui-rail--glide');
+      return;
+    }
+    const railBox = rail.getBoundingClientRect();
+    const box = on.getBoundingClientRect();
+    const shown = gliding.has(rail);
+    // A rail opening its first panel folds its labelled pills to icons, the
+    // buttons shrinking over a few frames; the highlight waits until the open
+    // button is an icon again (square) rather than fading in at a pill's
+    // width and then shrinking.
+    if (
+      !shown &&
+      (rail.classList.contains('ui-rail--expanded') ||
+        box.width > box.height + 2)
+    )
+      return;
+    // Appearing from nothing: jump into place, then fade in.
+    rail.classList.toggle('ui-rail--glide-jump', !shown);
+    rail.style.setProperty(
+      '--rail-glide-x',
+      `${box.left - railBox.left - rail.clientLeft}px`,
+    );
+    rail.style.setProperty(
+      '--rail-glide-y',
+      `${box.top - railBox.top - rail.clientTop}px`,
+    );
+    rail.style.setProperty('--rail-glide-w', `${box.width}px`);
+    rail.style.setProperty('--rail-glide-h', `${box.height}px`);
+    rail.classList.add('ui-rail--glide');
+    gliding.add(rail);
+    if (!shown)
+      win.requestAnimationFrame(() =>
+        rail.classList.remove('ui-rail--glide-jump'),
+      );
+  }
+
+  // Follow the rails for a few frames after any change, as their items
+  // resize while labels fold away.
+  function follow(frames = 24) {
+    win.cancelAnimationFrame(frame);
+    let left = frames;
+    const tick = () => {
+      if (removed) return;
+      watchRails();
+      doc.querySelectorAll('.ui-rail').forEach(glide);
+      if ((left -= 1) > 0) frame = win.requestAnimationFrame(tick);
+    };
+    tick();
+  }
+
+  const observer =
+    typeof win.MutationObserver === 'function'
+      ? new win.MutationObserver((records) => {
+          // A rail item opened or closed. Nothing here writes aria-pressed,
+          // and the work waits for the next frame, so this never feeds itself.
+          if (
+            records.some((record) =>
+              record.target.classList?.contains('ui-rail__item'),
+            )
+          )
+            win.requestAnimationFrame(() => follow());
+        })
+      : null;
+  observer?.observe(doc.body, {
+    subtree: true,
+    attributes: true,
+    attributeFilter: ['aria-pressed'],
+  });
+
+  // A rail also changes shape with nothing pressed or released: hidden and
+  // shown again (Context docked and undocked), or turned from a column to a
+  // row (panels moved to the screen edge). Its highlight is placed again
+  // whenever its size changes, so it is never left where an icon was.
+  const sized =
+    typeof win.ResizeObserver === 'function'
+      ? new win.ResizeObserver(() => follow(2))
+      : null;
+  const watched = new WeakSet();
+  const watchRails = () => {
+    if (!sized) return;
+    doc.querySelectorAll('.ui-rail').forEach((rail) => {
+      if (watched.has(rail)) return;
+      watched.add(rail);
+      sized.observe(rail);
+    });
+  };
+  watchRails();
+
+  // ── The edge strip ──
+  /** The rail whose strip holds the point, unless a control there owns it. */
+  function railAt(x, target) {
+    if (doc.body.classList.contains('mobile-shell') || coarse?.matches)
+      return null;
+    for (const { side, rail } of rails()) {
+      const box = rail.getBoundingClientRect();
+      // From the screen edge to just past the rail, but never wider than a
+      // rail's own column: a rail laid out as a row across the top of its
+      // panels would otherwise claim most of the panel's width.
+      const width = doc.documentElement.clientWidth;
+      const inStrip =
+        side === 'left'
+          ? x <= Math.min(box.right + STRIP_MARGIN, STRIP_MAX)
+          : x >= Math.max(box.left - STRIP_MARGIN, width - STRIP_MAX);
+      if (!inStrip) continue;
+      if (rail.contains(target)) return rail;
+      if (target?.closest?.(OWN_CONTROLS)) return null;
+      return rail;
+    }
+    return null;
+  }
+
+  function setHot(rail) {
+    if (rail === hot) return;
+    // A held step belongs to the strip it was made in; leaving drops it, so
+    // coming back later does not set it off with no wheel turned.
+    if (heldStep) {
+      win.clearTimeout(heldStep);
+      heldStep = 0;
+    }
+    hot?.classList.remove('ui-rail--edge-hot');
+    hot = rail;
+    travel = 0;
+    hot?.classList.add('ui-rail--edge-hot');
+    follow(2);
+  }
+
+  function onMove(event) {
+    setHot(railAt(event.clientX, event.target));
+  }
+
+  function onLeave(event) {
+    if (!event.relatedTarget) setHot(null);
+  }
+
+  function step(direction) {
+    const list = items(hot);
+    if (!list.length) return;
+    const current = list.findIndex(
+      (item) => item.getAttribute('aria-pressed') === 'true',
+    );
+    // Past either end, carry on from the other.
+    const nextIndex =
+      current < 0
+        ? direction > 0
+          ? 0
+          : list.length - 1
+        : (current + direction + list.length) % list.length;
+    if (nextIndex === current) return;
+    const target = list[nextIndex];
+    target.click();
+    const panel = doc.getElementById(target.dataset.railItem);
+    if (panel) {
+      panel.classList.remove('rail-switch-down', 'rail-switch-up');
+      void panel.offsetWidth;
+      panel.classList.add(
+        direction > 0 ? 'rail-switch-down' : 'rail-switch-up',
+      );
+      // The classes come off when the slide ends, or after a moment where
+      // there is no slide to end (reduced motion).
+      const settle = () => {
+        win.clearTimeout(timer);
+        panel.removeEventListener('animationend', settle);
+        panel.classList.remove('rail-switch-down', 'rail-switch-up');
+      };
+      const timer = win.setTimeout(settle, 600);
+      panel.addEventListener('animationend', settle);
+    }
+    follow();
+  }
+
+  function onWheel(event) {
+    // Pinch zoom, and sideways or empty moves (trackpads send them mid-swipe),
+    // are left alone: they neither step nor turn a gesture round.
+    if (event.ctrlKey || !event.deltaY) return;
+    const now = win.performance?.now?.() ?? Date.now();
+    const inGesture = now - lastWheel <= GESTURE_GAP_MS;
+    // Recheck: the pointer may not have moved since the panels changed.
+    const stillHot =
+      Boolean(hot) && railAt(event.clientX, event.target) === hot;
+    if (!stillHot) {
+      setHot(null);
+      // The rest of a gesture that has already stepped is used up here, so
+      // its coasting does not go on to zoom the globe or scroll what opened
+      // under the pointer.
+      if (stepped && inGesture && now - steppedAt <= COAST_MAX_MS) {
+        event.preventDefault();
+        event.stopPropagation();
+        lastWheel = now;
+      }
+      return;
+    }
+    event.preventDefault();
+    event.stopPropagation();
+    // Line- and page-based wheels report far smaller numbers than pixels.
+    const deltaY =
+      event.deltaMode === 1
+        ? event.deltaY * LINE_PX
+        : event.deltaMode === 2
+          ? event.deltaY * win.innerHeight
+          : event.deltaY;
+    const speed = Math.abs(deltaY);
+    // A new gesture: after a pause, after turning round, a mouse wheel notch,
+    // or a fresh flick while the last one is still coasting. A flick is a
+    // rise in speed after the gesture has clearly slowed, and not in the
+    // moment after a step: a swipe is still speeding up when it first steps.
+    const turned = travel && Math.sign(deltaY) !== Math.sign(travel);
+    const cooled = now - steppedAt > STEP_COOLDOWN_MS;
+    // Every event from a line- or page-based wheel is a notch.
+    const notch =
+      stepped && cooled && (speed >= NOTCH_DELTA || event.deltaMode > 0);
+    const flick =
+      stepped && cooled && slowed && speed > Math.max(8, lastSpeed * 1.8);
+    if (!inGesture || turned || notch || flick) {
+      // A held step belongs to the motion it came from; a reversal or a new
+      // flick replaces it rather than queueing behind it.
+      if (turned && heldStep) {
+        win.clearTimeout(heldStep);
+        heldStep = 0;
+      }
+      travel = 0;
+      stepped = false;
+      peakSpeed = 0;
+      slowed = false;
+    }
+    lastWheel = now;
+    lastSpeed = speed;
+    peakSpeed = Math.max(peakSpeed, speed);
+    if (stepped) {
+      if (speed < peakSpeed * 0.5) slowed = true;
+      return;
+    }
+    travel += deltaY;
+    if (Math.abs(travel) < STEP_DELTA) return;
+    stepped = true;
+    const direction = Math.sign(travel);
+    const wait = STEP_GAP_MS - (now - steppedAt);
+    if (wait <= 0) {
+      steppedAt = now;
+      step(direction);
+      return;
+    }
+    // Too soon after the last step: hold this one until the gap has passed.
+    if (heldStep) return;
+    const heldRail = hot;
+    heldStep = win.setTimeout(() => {
+      heldStep = 0;
+      // The pointer may have left the strip, or moved to the other rail,
+      // meanwhile; then nothing steps.
+      if (!hot || hot !== heldRail) return;
+      steppedAt = win.performance?.now?.() ?? Date.now();
+      step(direction);
+    }, wait);
+  }
+
+  const onResize = () => follow(2);
+  doc.addEventListener('pointermove', onMove, { passive: true });
+  doc.addEventListener('pointerout', onLeave, { passive: true });
+  win.addEventListener('wheel', onWheel, { capture: true, passive: false });
+  win.addEventListener('resize', onResize, { passive: true });
+  follow();
+
+  return () => {
+    removed = true;
+    win.clearTimeout(heldStep);
+    setHot(null);
+    observer?.disconnect();
+    sized?.disconnect();
+    win.cancelAnimationFrame(frame);
+    doc.removeEventListener('pointermove', onMove);
+    doc.removeEventListener('pointerout', onLeave);
+    win.removeEventListener('wheel', onWheel, { capture: true });
+    win.removeEventListener('resize', onResize);
+    doc.querySelectorAll('.ui-rail').forEach((rail) => {
+      rail.classList.remove(
+        'ui-rail--glide',
+        'ui-rail--glide-jump',
+        'ui-rail--edge-hot',
+      );
+    });
+  };
+}

src/ui/railEdgeScroll.test.mjs

@@ -0,0 +1,177 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { Window } from 'happy-dom';
+import { installRailEdgeScroll } from './railEdgeScroll.js';
+
+// A page with a left and a right rail of three items each, laid out by hand:
+// happy-dom does no layout, so boxes and the clock are stubbed.
+function page({ rtl = false } = {}) {
+  const window = new Window({ width: 1600, height: 900 });
+  const doc = window.document;
+  let now = 1000;
+  const timers = new Map();
+  let nextTimer = 1;
+  window.performance.now = () => now;
+  window.setTimeout = (fn, ms) => {
+    const id = nextTimer++;
+    timers.set(id, { fn, at: now + ms });
+    return id;
+  };
+  window.clearTimeout = (id) => timers.delete(id);
+  window.requestAnimationFrame = () => 0;
+  window.cancelAnimationFrame = () => {};
+  Object.defineProperty(doc.documentElement, 'clientWidth', { value: 1600 });
+  const box = (el, left, top, width, height) => {
+    el.getBoundingClientRect = () => ({
+      left,
+      top,
+      width,
+      height,
+      right: left + width,
+      bottom: top + height,
+    });
+    Object.defineProperty(el, 'offsetWidth', { get: () => width });
+  };
+  const clicks = [];
+  const rail = (name, left) => {
+    const el = doc.createElement('div');
+    el.className = `ui-rail ui-rail--${name}`;
+    box(el, left, 200, 40, 120);
+    for (let i = 0; i < 3; i++) {
+      const item = doc.createElement('button');
+      item.className = 'ui-rail__item';
+      item.dataset.railItem = `${name}-${i}`;
+      item.setAttribute('aria-pressed', i === 0 ? 'true' : 'false');
+      box(item, left + 4, 204 + i * 40, 32, 32);
+      item.addEventListener('click', () => {
+        clicks.push(item.dataset.railItem);
+        for (const other of el.children)
+          other.setAttribute('aria-pressed', String(other === item));
+      });
+      el.append(item);
+    }
+    doc.body.append(el);
+    return el;
+  };
+  // In a right-to-left language the left stack's rail is on the right edge.
+  const left = rail('left', rtl ? 1550 : 10);
+  const right = rail('right', rtl ? 10 : 1550);
+  const remove = installRailEdgeScroll(doc);
+  const wheel = (x, deltaY, { deltaMode = 0, target = doc.body } = {}) => {
+    // happy-dom leaves clientX off these events, so it is set by hand.
+    const at = (event) => Object.defineProperty(event, 'clientX', { value: x });
+    target.dispatchEvent(
+      at(new window.PointerEvent('pointermove', { bubbles: true })),
+    );
+    const event = at(
+      new window.WheelEvent('wheel', {
+        bubbles: true,
+        cancelable: true,
+        deltaY,
+        deltaMode,
+      }),
+    );
+    target.dispatchEvent(event);
+    return event;
+  };
+  const advance = (ms) => {
+    now += ms;
+    for (const [id, timer] of [...timers]) {
+      if (timer.at > now) continue;
+      timers.delete(id);
+      timer.fn();
+    }
+  };
+  return { window, doc, left, right, clicks, wheel, advance, remove };
+}
+
+test('a wheel in the left strip steps that rail and keeps the globe from zooming', () => {
+  const p = page();
+  const event = p.wheel(20, 120);
+  assert.equal(event.defaultPrevented, true);
+  assert.deepEqual(p.clicks, ['left-1']);
+  p.remove();
+});
+
+test('a line-based mouse wheel steps one panel per notch', () => {
+  const p = page();
+  p.wheel(20, 3, { deltaMode: 1 });
+  p.advance(600);
+  p.wheel(20, 3, { deltaMode: 1 });
+  assert.deepEqual(p.clicks, ['left-1', 'left-2']);
+  p.remove();
+});
+
+test('a rail hidden by clean view or recording leaves the wheel to the globe', () => {
+  const p = page();
+  p.left.checkVisibility = () => false;
+  const event = p.wheel(20, 120);
+  assert.equal(event.defaultPrevented, false);
+  assert.deepEqual(p.clicks, []);
+  p.remove();
+});
+
+test('right to left: the wheel at each screen edge steps the rail on that edge', () => {
+  const p = page({ rtl: true });
+  p.wheel(1580, 120);
+  p.advance(600);
+  p.wheel(20, 120);
+  assert.deepEqual(p.clicks, ['left-1', 'right-1']);
+  p.remove();
+});
+
+test('after a step, the wheel goes back to the page once the coasting is over', () => {
+  const p = page();
+  p.wheel(20, 120);
+  // The pointer moves off the strip while the gesture still coasts.
+  let event;
+  for (let i = 0; i < 20; i++) {
+    p.advance(100);
+    event = p.wheel(800, 30);
+  }
+  assert.equal(event.defaultPrevented, false);
+  assert.deepEqual(p.clicks, ['left-1']);
+  p.remove();
+});
+
+test('a held step is dropped when the pointer leaves the strip, even if it comes back', () => {
+  const p = page();
+  p.wheel(20, 120);
+  p.advance(250);
+  p.wheel(20, -120); // turns round: a second step, held for the gap
+  p.wheel(800, 0); // leaves the strip
+  p.wheel(20, 0); // and returns before the gap ends
+  p.advance(600);
+  assert.deepEqual(p.clicks, ['left-1']);
+  p.remove();
+});
+
+test('removing it stops edge scrolling', () => {
+  const p = page();
+  p.remove();
+  const event = p.wheel(20, 120);
+  assert.equal(event.defaultPrevented, false);
+  assert.deepEqual(p.clicks, []);
+});
+
+test('a sideways move mid-swipe neither turns the gesture round nor steps again', () => {
+  const p = page();
+  p.wheel(20, 60);
+  p.advance(50);
+  const sideways = p.wheel(20, 0);
+  p.advance(50);
+  p.wheel(20, 40); // the same swipe coasting on
+  assert.equal(sideways.defaultPrevented, false);
+  assert.deepEqual(p.clicks, ['left-1']);
+  p.remove();
+});
+
+test('an open dialog near the edge keeps its own wheel', () => {
+  const p = page();
+  const dialog = p.doc.createElement('dialog');
+  p.doc.body.append(dialog);
+  const event = p.wheel(20, 120, { target: dialog });
+  assert.equal(event.defaultPrevented, false);
+  assert.deepEqual(p.clicks, []);
+  p.remove();
+});

src/ui/rightPanelRail.js

@@ -31,6 +31,20 @@ function settledLeftRailTop(leftStack, viewportHeight, getComputedStyle) {
   return Number.isFinite(targetPct) ? (targetPct * viewportHeight) / 100 : top;
 }
 
+/**
+ * An element's CSS `top` in pixels where it will settle: the end of a running
+ * `top` transition, else its computed value. NaN when it cannot be read.
+ */
+function settledCssTop(element, getComputedStyle) {
+  if (!element) return NaN;
+  const transition = element
+    .getAnimations?.()
+    .find((animation) => animation.transitionProperty === 'top');
+  const target = parseFloat(transition?.effect?.getKeyframes?.().at(-1)?.top);
+  if (Number.isFinite(target)) return target;
+  return parseFloat(getComputedStyle(element).top);
+}
+
 /**
  * Measure and place the right panel rail for one synchronous layout pass.
  * The caller owns scheduling, obstacle selection, disclosure preferences and
@@ -126,9 +140,20 @@ export function layoutRightPanelRail({
     viewportHeight,
     getComputedStyle,
   );
-  // Align with the left rail's buttons, which hold still while its stack moves.
+  // Align with the left rail's buttons, which hold still while its stack moves:
-  const leftRailOffset =
+  // the rail's own settled `top` inside the stack, so every left layout is
-    parseFloat(leftStack?.style.getPropertyValue('--panel-rail-offset')) || 0;
+  // followed (a layout may pin the rail to the stack's top whatever the
+  // offset says). The stack's offset is the fallback when there is no rail.
+  const leftRailInset = settledCssTop(
+    leftStack?.querySelector?.('.gev-panel-rail') ?? null,
+    getComputedStyle,
+  );
+  // A rail that sits lower in its stack has only made room above itself for
+  // the open panel's own icon, which stays at the stack's top: the column's
+  // top has not moved, so that inset is not followed.
+  const leftRailOffset = Number.isFinite(leftRailInset)
+    ? Math.min(0, leftRailInset)
+    : parseFloat(leftStack?.style.getPropertyValue('--panel-rail-offset')) || 0;
   const alignedTop = Number.isFinite(leftStackTop)
     ? leftStackTop + leftRailOffset
     : viewportHeight * 0.26;
@@ -206,6 +231,18 @@ export function layoutRightPanelRail({
       0,
     ) +
     gap * Math.max(0, measuredPanels.length - 1);
+  // An open Context panel takes the column's full height: up to just under
+  // the HUD readouts at the top of the screen, down to the usual bottom.
+  // CCTV does the same, so its feed and controls have the room.
+  const FULL_HEIGHT = new Set(['global-context-panel', 'cctv-panel']);
+  const contextOpen = panels.some(
+    (panel) =>
+      FULL_HEIGHT.has(panel.id) && !panel.classList.contains('collapsed'),
+  );
+  // Every panel starts level with the left rail, open or not, so the two
+  // rails line up in every HUD layout (Minimal has no top-right readout to
+  // push this column down) and switching between Context, CCTV and Street
+  // Level does not move it. Only the two above also stretch to the bottom.
   const layout = resolveHudRailLayout({
     viewportHeight,
     panelHeight: naturalHeight,
@@ -221,9 +258,11 @@ export function layoutRightPanelRail({
   const { safeTop, safeBottom, maxHeight: availableHeight } = layout;
   const stabilityBand = Math.max(48, viewportHeight * 0.06);
   const wasFocused = stack.classList.contains('layout-focus');
-  const shouldFocus = wasFocused
+  const shouldFocus =
-    ? naturalHeight >= availableHeight - stabilityBand
+    contextOpen ||
-    : naturalHeight > availableHeight;
+    (wasFocused
+      ? naturalHeight >= availableHeight - stabilityBand
+      : naturalHeight > availableHeight);
   const layoutTop = shouldFocus ? safeTop : layout.top;
   const collapsedHeight = visiblePanels.reduce(
     (total, panel) =>

src/ui/shellLifecycle.test.mjs

@@ -259,7 +259,7 @@ test('recording restores the original HUD after repeated entry and revokes retai
   }
 });
 
-test('weather rail orders between CCTV and Context, observes and presents chrome', (t) => {
+test('Context leads the right rail, weather follows CCTV, observes and presents chrome', (t) => {
   const f = fixture();
   const observed = new Set();
   const previousResizeObserver = globalThis.ResizeObserver;
@@ -319,7 +319,7 @@ test('weather rail orders between CCTV and Context, observes and presents chrome
     owner._initRightPanelAdaptiveLayout();
     assert.deepEqual(
       stack.children.map((panel) => panel.id),
-      ['pp-toggles', 'cctv-panel', 'weather-panel', 'global-context-panel'],
+      ['global-context-panel', 'pp-toggles', 'cctv-panel', 'weather-panel'],
     );
     assert.ok(observed.has(weather));
     // Moving a panel into the rail leaves its state as it was.

src/ui/styles/left-tools.css

@@ -0,0 +1,37 @@
+/* Visual in the left column: it takes clicks (the column itself lets them
+   through to the globe) and stays inside the column, scrolling as a whole. */
+#left-panel-stack > #pp-toggles {
+  position: relative;
+  inset: auto;
+  flex: 0 1 var(--left-panel-allocated-height, auto);
+  min-height: 0;
+  max-height: var(--left-panel-allocated-height, 100%);
+  overflow-y: auto;
+  pointer-events: auto;
+}
+
+#left-panel-stack > #pp-toggles.collapsed {
+  display: none;
+}
+
+/* ── Expanded panel width ───────────────────────────────────────────────
+   Data Layers opens 15px wider than it used to (280 → 295px), and that is
+   the narrowest any side panel opens to; wider ones (Context, CCTV,
+   Authoring) keep their own width. */
+:root {
+  --side-panel-min-expanded-width: 295px;
+}
+
+#data-panel,
+#utilities-panel {
+  --panel-expanded-width: var(--side-panel-min-expanded-width);
+}
+
+#left-panel-stack > #pp-toggles:not(.collapsed) {
+  --pp-expanded-width: var(--side-panel-min-expanded-width);
+  width: var(--side-panel-min-expanded-width);
+}
+
+:is(#left-panel-stack, #right-context-rail) > [data-panel-id]:not(.collapsed) {
+  min-width: var(--side-panel-min-expanded-width);
+}

src/ui/styles/mobile-shell.css

@@ -129,7 +129,9 @@ body.mobile-shell #right-context-rail {
 body.mobile-shell[data-mobile-sheet='layers'] #left-panel-stack,
 body.mobile-shell[data-mobile-sheet='cameras'] #right-context-rail,
 body.mobile-shell[data-mobile-sheet='context'] #right-context-rail,
-body.mobile-shell[data-mobile-sheet='more'] #right-context-rail {
+/* Visual opens from the left rail on wider screens, so it lives in the left
+   stack and the More sheet is that stack showing Visual alone. */
+body.mobile-shell[data-mobile-sheet='more'] #left-panel-stack {
   position: fixed;
   top: auto;
   right: 0;
@@ -189,7 +191,7 @@ body.mobile-shell[data-mobile-sheet='context']
 body.mobile-shell[data-mobile-sheet='context']
   #right-context-rail
   > #recent-imagery-panel:not([hidden]),
-body.mobile-shell[data-mobile-sheet='more'] #right-context-rail > #pp-toggles {
+body.mobile-shell[data-mobile-sheet='more'] #left-panel-stack > #pp-toggles {
   position: relative;
   inset: auto;
   display: block;

src/ui/styles/overlays.css

@@ -310,8 +310,10 @@
   bottom: 12vh;
 }
 
+/* Minimal keeps its coordinates in the corner block, where the other layouts
+   have them; the full-width strip would only repeat the same position. */
 #intel-hud[data-variant='minimal'] .hud-bottom-bar {
-  display: flex;
+  display: none;
   bottom: calc(12vh + 4rem);
 }
 

src/ui/styles/panel-edge.css

@@ -0,0 +1,100 @@
+/* ── Panels over the rail ───────────────────────────────────────────────
+   Each panel header's edge switch (UiPanelEdge) slides that side's open
+   panels over their rail to the screen edge; the rail stays underneath. */
+.ui-panel-edge {
+  display: grid;
+  flex: none;
+  place-items: center;
+  width: 22px;
+  height: 22px;
+  padding: 0;
+  color: rgba(206, 232, 239, 0.6);
+  background: rgba(255, 255, 255, 0.03);
+  border: 1px solid rgba(255, 255, 255, 0.12);
+  border-radius: 6px;
+  cursor: pointer;
+}
+
+.ui-panel-edge .material-symbols-outlined {
+  font-size: 14px;
+}
+
+.ui-panel-edge:hover,
+.ui-panel-edge:focus-visible {
+  color: var(--text-primary, #e8eaed);
+  border-color: rgba(255, 255, 255, 0.24);
+}
+
+.ui-panel-edge[aria-pressed='true'] {
+  color: #36dcff;
+  background: rgba(54, 220, 255, 0.12);
+  border-color: rgba(54, 220, 255, 0.45);
+}
+
+/* Collapsed panels hide the switch; it only means something once open. */
+.panel-collapsible.collapsed .ui-panel-edge {
+  display: none;
+}
+
+/* Right: open panels move right by the rail's width and sit over it. */
+body.panels-edge-right:not(.mobile-shell):not(.cockpit-mode)
+  #right-context-rail
+  > :not(.gev-panel-rail) {
+  z-index: 2;
+  transform: translateX(var(--panel-rail-clearance, 48px));
+}
+
+/* Left: the same, moving left. */
+body.panels-edge-left:not(.mobile-shell):not(.cockpit-mode)
+  #left-panel-stack
+  > :not(.gev-panel-rail) {
+  z-index: 2;
+  transform: translateX(calc(-1 * var(--panel-rail-clearance, 48px)));
+}
+
+body.mobile-shell .ui-panel-edge,
+body.cockpit-mode .ui-panel-edge {
+  display: none;
+}
+
+/* ── Edge mode with a panel open: the rail's icons move to a row along the
+   top of the panel, and the panel steps down to make room. ── */
+:root {
+  --edge-rail-row: 50px;
+}
+
+body.panels-edge-left:not(.mobile-shell):not(.cockpit-mode)
+  .gev-panel-rail--left:has(.ui-rail--collapsible:not(.ui-rail--expanded)),
+body.panels-edge-right:not(.mobile-shell):not(.cockpit-mode)
+  .gev-panel-rail--right:has(.ui-rail--collapsible:not(.ui-rail--expanded)) {
+  top: 0 !important;
+  z-index: 3;
+}
+
+body.panels-edge-left:not(.mobile-shell):not(.cockpit-mode)
+  .gev-panel-rail--left
+  .ui-rail--collapsible:not(.ui-rail--expanded),
+body.panels-edge-right:not(.mobile-shell):not(.cockpit-mode)
+  .gev-panel-rail--right
+  .ui-rail--collapsible:not(.ui-rail--expanded) {
+  flex-direction: row;
+  width: max-content;
+  gap: 4px;
+}
+
+body.panels-edge-left:not(.mobile-shell):not(.cockpit-mode)
+  #left-panel-stack
+  > :not(.gev-panel-rail):not(.collapsed) {
+  transform: translate(
+    calc(-1 * var(--panel-rail-clearance, 48px)),
+    var(--edge-rail-row)
+  );
+  max-height: calc(100% - var(--edge-rail-row)) !important;
+}
+
+body.panels-edge-right:not(.mobile-shell):not(.cockpit-mode)
+  #right-context-rail
+  > :not(.gev-panel-rail):not(.collapsed) {
+  transform: translate(var(--panel-rail-clearance, 48px), var(--edge-rail-row));
+  max-height: calc(100% - var(--edge-rail-row)) !important;
+}

src/ui/styles/rail-edge.css

@@ -0,0 +1,103 @@
+/* ── Side rails: sliding highlight and edge scrolling ──────────────────
+   The open item's highlight is drawn once per rail, under the icons, and
+   slides from item to item when the panel changes. With the pointer in a
+   screen edge's strip, the rail's border lights up a little to say the wheel
+   now steps through its panels; the panel that opens slides in from the
+   direction of travel. */
+.ui-rail {
+  position: relative;
+  transition:
+    border-color 240ms ease,
+    border-radius var(--transition-fast);
+}
+
+.ui-rail.ui-rail--edge-hot {
+  border-color: rgba(48, 194, 224, 0.4);
+}
+
+/* The highlight itself, matching an open item's own look. */
+.ui-rail::before {
+  position: absolute;
+  top: 0;
+  left: 0;
+  z-index: 0;
+  width: var(--rail-glide-w, 32px);
+  height: var(--rail-glide-h, 32px);
+  background: var(--accent-dim);
+  border: 1px solid var(--accent-dim);
+  border-radius: var(--btn-radius);
+  box-sizing: border-box;
+  content: '';
+  opacity: 0;
+  pointer-events: none;
+  transform: translate(var(--rail-glide-x, 0), var(--rail-glide-y, 0));
+  /* Only the position slides. The size follows at once: it changes only
+     when the rail changes shape (its labelled pills folding to icons as a
+     panel opens), and a size easing there reads as a stretch. */
+  transition:
+    transform 380ms cubic-bezier(0.22, 1, 0.36, 1),
+    border-radius var(--transition-fast),
+    opacity 200ms ease;
+}
+
+.ui-rail--expanded::before {
+  border-radius: 16px;
+}
+
+.ui-rail.ui-rail--glide::before {
+  opacity: 1;
+}
+
+.ui-rail.ui-rail--glide-jump::before {
+  transition: opacity 200ms ease;
+}
+
+/* While the shared highlight shows, the items stay clear and sit above it;
+   the open item keeps its accent colour, which eases in as it arrives. */
+.ui-rail--glide .ui-rail__item {
+  z-index: 1;
+  transition:
+    color 300ms ease,
+    background var(--transition-fast),
+    border-color var(--transition-fast),
+    border-radius var(--transition-fast);
+}
+
+.ui-rail--glide .ui-rail__item--on,
+.ui-rail--glide .ui-rail__item--on:hover:not(:disabled) {
+  background: transparent;
+  border-color: transparent;
+}
+
+.rail-switch-down {
+  animation: rail-switch-down 340ms cubic-bezier(0.22, 1, 0.36, 1);
+}
+
+.rail-switch-up {
+  animation: rail-switch-up 340ms cubic-bezier(0.22, 1, 0.36, 1);
+}
+
+@keyframes rail-switch-down {
+  from {
+    opacity: 0;
+    translate: 0 16px;
+  }
+}
+
+@keyframes rail-switch-up {
+  from {
+    opacity: 0;
+    translate: 0 -16px;
+  }
+}
+
+@media (prefers-reduced-motion: reduce) {
+  .ui-rail::before {
+    transition: opacity 200ms ease;
+  }
+
+  .rail-switch-down,
+  .rail-switch-up {
+    animation: none;
+  }
+}

src/ui/styles/rail-split.css

@@ -0,0 +1,282 @@
+/* The left rail's icons keep their places whether or not a panel is open;
+   only the highlight moves to the open one. */
+
+/* With nothing open, the icons and their names split into two glass panels
+   side by side: the plain icon rail, and a name panel beside it with one row
+   per icon. A name is part of its button, so clicking it opens that panel. */
+.gev-panel-rail--left .ui-rail--expanded {
+  position: relative;
+  border-radius: calc(var(--btn-radius) + 4px);
+}
+
+.gev-panel-rail--left .ui-rail--expanded .ui-rail__item {
+  width: 32px;
+  border-radius: var(--btn-radius);
+}
+
+.gev-panel-rail--left .ui-rail--expanded::after {
+  content: '';
+  position: absolute;
+  top: -1px;
+  bottom: -1px;
+  left: calc(100% + 6px);
+  width: 170px;
+  border: 1px solid var(--glass-border);
+  border-radius: calc(var(--btn-radius) + 4px);
+  background: var(--glass-bg);
+  backdrop-filter: blur(20px);
+  -webkit-backdrop-filter: blur(20px);
+  pointer-events: none;
+}
+
+.gev-panel-rail--left .ui-rail--expanded .ui-rail__label {
+  position: absolute;
+  z-index: 1;
+  top: 0;
+  bottom: 0;
+  /* Past the rail's padding and border, the 6px gap, and the name panel's
+     border and inner padding. */
+  left: calc(100% + 24px);
+  display: flex;
+  align-items: center;
+  max-width: 150px;
+  margin: 0;
+}
+
+.gev-panel-rail--left .ui-rail--expanded .ui-rail__item:hover .ui-rail__label {
+  color: var(--text-primary);
+}
+
+/* The column rises to sit just under the HUD readout instead of leaving a
+   gap above it, with or without a panel open, so opening one doesn't move
+   the rail down. */
+#left-panel-stack {
+  top: calc(
+    var(--left-stack-safe-top, var(--left-stack-top)) +
+      var(--panel-rail-lift, 0px)
+  );
+}
+
+/* The right rail splits the same way with nothing open, mirrored: the icon
+   rail stays on the screen edge and the name panel sits to its left. */
+.gev-panel-rail--right .ui-rail--expanded {
+  position: relative;
+  border-radius: calc(var(--btn-radius) + 4px);
+}
+
+.gev-panel-rail--right .ui-rail--expanded .ui-rail__item {
+  width: 32px;
+  border-radius: var(--btn-radius);
+}
+
+.gev-panel-rail--right .ui-rail--expanded::after {
+  content: '';
+  position: absolute;
+  top: -1px;
+  bottom: -1px;
+  right: calc(100% + 6px);
+  width: 170px;
+  border: 1px solid var(--glass-border);
+  border-radius: calc(var(--btn-radius) + 4px);
+  background: var(--glass-bg);
+  backdrop-filter: blur(20px);
+  -webkit-backdrop-filter: blur(20px);
+  pointer-events: none;
+}
+
+.gev-panel-rail--right .ui-rail--expanded .ui-rail__label {
+  position: absolute;
+  z-index: 1;
+  top: 0;
+  bottom: 0;
+  /* From the button's left edge back past the rail's padding and border,
+     the 6px gap and the 170px name panel, to the panel's inner padding. */
+  left: -168px;
+  display: flex;
+  align-items: center;
+  max-width: 150px;
+  margin: 0;
+}
+
+.gev-panel-rail--right .ui-rail--expanded .ui-rail__item:hover .ui-rail__label {
+  color: var(--text-primary);
+}
+
+/* In clean view the screen-edge gutters stay empty: the HUD's vertical edge
+   readouts (ONA / COLL on the left, BAND / BITS / LVL on the right) are not
+   shown. Cyber lays its HUD out differently and keeps them. */
+:root:not([data-ui-theme='cyber']) body.ui-clean-view #intel-hud .hud-edge {
+  display: none !important;
+}
+
+/* The bottom-right readout (GSD / ALT / AIS) has one more line than the
+   bottom-left one (MGRS / coordinates); it drops by that line so the two
+   corners start level. */
+#intel-hud[data-variant='tactical'] .hud-bottom-right {
+  bottom: calc(2vh + 6.5rem - 26px);
+}
+
+@media (min-width: 1200px) {
+  #intel-hud[data-variant='tactical'] .hud-bottom-right {
+    bottom: calc(4.2rem - 26px);
+  }
+}
+
+/* ── Contrast: rails and name panels read clearly over dark space as well
+   as bright imagery. ── */
+:is(.gev-panel-rail--left, .gev-panel-rail--right) .ui-rail {
+  background: rgba(16, 20, 28, 0.82) !important;
+  border-color: rgba(255, 255, 255, 0.14) !important;
+  box-shadow:
+    0 6px 20px rgba(0, 0, 0, 0.45),
+    inset 0 1px 0 rgba(255, 255, 255, 0.05);
+}
+
+:is(.gev-panel-rail--left, .gev-panel-rail--right) .ui-rail--expanded::after {
+  background: rgba(16, 20, 28, 0.82) !important;
+  border-color: rgba(255, 255, 255, 0.14) !important;
+  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.45);
+}
+
+:is(.gev-panel-rail--left, .gev-panel-rail--right) .ui-rail__item {
+  color: rgba(225, 236, 242, 0.88);
+}
+
+:is(.gev-panel-rail--left, .gev-panel-rail--right) .ui-rail__label {
+  color: rgba(225, 236, 242, 0.82) !important;
+}
+
+:is(.gev-panel-rail--left, .gev-panel-rail--right) .ui-rail__item:hover {
+  color: #fff;
+}
+
+/* The open item takes the accent colour; its highlight is the rail's shared
+   one, which slides to it. The button carries no fill of its own: as a rail
+   folds its labelled pills to icons, a fill on the shrinking button would
+   read as the highlight stretching. */
+:is(.gev-panel-rail--left, .gev-panel-rail--right)
+  .ui-rail__item.ui-rail__item--on {
+  color: #00d4ff !important;
+}
+
+:is(.gev-panel-rail--left, .gev-panel-rail--right)
+  .ui-rail:not(.ui-rail--glide)
+  .ui-rail__item.ui-rail__item--on {
+  background: none;
+  border-color: transparent;
+}
+
+:is(.gev-panel-rail--left, .gev-panel-rail--right) .ui-rail::before {
+  background: rgba(0, 212, 255, 0.15);
+  border-color: rgba(0, 212, 255, 0.28);
+}
+
+/* ── The open icon is its own island ──
+   With a panel open, the rail's glass is drawn in pieces behind its icons:
+   one piece for the open icon, and one for each run of icons above and below
+   it. The icons keep their places, open or not; the spacing between them is
+   what leaves room for the break. */
+:is(.gev-panel-rail--left, .gev-panel-rail--right) .ui-rail {
+  gap: 12px;
+}
+
+:is(
+    body:not(.panels-edge-left) .gev-panel-rail--left,
+    body:not(.panels-edge-right) .gev-panel-rail--right
+  )
+  .ui-rail--collapsible:not(.ui-rail--expanded):has(.ui-rail__item--on) {
+  background: none !important;
+  border-color: transparent !important;
+  box-shadow: none !important;
+  backdrop-filter: none;
+  -webkit-backdrop-filter: none;
+}
+
+:is(
+    body:not(.panels-edge-left) .gev-panel-rail--left,
+    body:not(.panels-edge-right) .gev-panel-rail--right
+  )
+  .ui-rail--collapsible:not(.ui-rail--expanded):has(.ui-rail__item--on)
+  > .ui-tooltip::before {
+  position: absolute;
+  inset: -6px -5px;
+  z-index: -1;
+  background: rgba(16, 20, 28, 0.82);
+  border: solid rgba(255, 255, 255, 0.14);
+  border-width: 0 1px;
+  backdrop-filter: blur(20px);
+  -webkit-backdrop-filter: blur(20px);
+  content: '';
+  pointer-events: none;
+}
+
+/* The ends of the rail. */
+:is(
+    body:not(.panels-edge-left) .gev-panel-rail--left,
+    body:not(.panels-edge-right) .gev-panel-rail--right
+  )
+  .ui-rail--collapsible:not(.ui-rail--expanded):has(.ui-rail__item--on)
+  > .ui-tooltip:first-child::before {
+  top: -5px;
+  border-top-width: 1px;
+  border-top-left-radius: 14px;
+  border-top-right-radius: 14px;
+}
+
+:is(
+    body:not(.panels-edge-left) .gev-panel-rail--left,
+    body:not(.panels-edge-right) .gev-panel-rail--right
+  )
+  .ui-rail--collapsible:not(.ui-rail--expanded):has(.ui-rail__item--on)
+  > .ui-tooltip:last-child::before {
+  bottom: -5px;
+  border-bottom-width: 1px;
+  border-bottom-left-radius: 14px;
+  border-bottom-right-radius: 14px;
+}
+
+/* The runs stop short of the open icon. */
+:is(
+    body:not(.panels-edge-left) .gev-panel-rail--left,
+    body:not(.panels-edge-right) .gev-panel-rail--right
+  )
+  .ui-rail--collapsible:not(.ui-rail--expanded):has(.ui-rail__item--on)
+  > .ui-tooltip:has(+ .ui-tooltip > .ui-rail__item--on)::before {
+  bottom: -1px;
+  border-bottom-width: 1px;
+  border-bottom-left-radius: 14px;
+  border-bottom-right-radius: 14px;
+}
+
+:is(
+    body:not(.panels-edge-left) .gev-panel-rail--left,
+    body:not(.panels-edge-right) .gev-panel-rail--right
+  )
+  .ui-rail--collapsible:not(.ui-rail--expanded):has(.ui-rail__item--on)
+  > .ui-tooltip:has(> .ui-rail__item--on)
+  + .ui-tooltip::before {
+  top: -1px;
+  border-top-width: 1px;
+  border-top-left-radius: 14px;
+  border-top-right-radius: 14px;
+}
+
+/* The open icon's own piece. */
+:is(
+    body:not(.panels-edge-left) .gev-panel-rail--left,
+    body:not(.panels-edge-right) .gev-panel-rail--right
+  )
+  .ui-rail--collapsible:not(.ui-rail--expanded):has(.ui-rail__item--on)
+  > .ui-tooltip:has(> .ui-rail__item--on)::before {
+  inset: -4px -5px;
+  border-width: 1px;
+  border-radius: 14px;
+  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.45);
+}
+
+/* The side rails fold their labels away at once when a panel opens, and back
+   when it closes: easing the labels' width made every button visibly
+   stretch and shrink. Only their fade eases. */
+:is(.gev-panel-rail--left, .gev-panel-rail--right) .ui-rail__label {
+  transition: opacity var(--transition-fast);
+}

src/ui/styles/rtl.css

@@ -242,3 +242,47 @@ html[dir='rtl'] select.gev-field--compact {
 html[dir='rtl'] .rail-card-scale {
   direction: ltr;
 }
+
+/* ── Side rails, mirrored ──────────────────────────────────────────────
+   The left stack sits on the right edge, so the left rail's name panel
+   opens to its left and the right rail's to its right, each toward the
+   middle of the screen, as they do in left-to-right. */
+html[dir='rtl'] .gev-panel-rail--left .ui-rail--expanded::after {
+  right: calc(100% + 6px);
+  left: auto;
+}
+html[dir='rtl'] .gev-panel-rail--left .ui-rail--expanded .ui-rail__label {
+  right: calc(100% + 24px);
+  left: auto;
+}
+html[dir='rtl'] .gev-panel-rail--right .ui-rail--expanded::after {
+  right: auto;
+  left: calc(100% + 6px);
+}
+html[dir='rtl'] .gev-panel-rail--right .ui-rail--expanded .ui-rail__label {
+  right: auto;
+  left: calc(100% + 24px);
+}
+
+/* Panels moved to the screen edge slide over their rail toward that edge. */
+html[dir='rtl']
+  body.panels-edge-left:not(.mobile-shell):not(.cockpit-mode)
+  #left-panel-stack
+  > :not(.gev-panel-rail) {
+  transform: translateX(var(--panel-rail-clearance, 48px));
+}
+html[dir='rtl']
+  body.panels-edge-left:not(.mobile-shell):not(.cockpit-mode)
+  #left-panel-stack
+  > :not(.gev-panel-rail):not(.collapsed) {
+  transform: translate(var(--panel-rail-clearance, 48px), var(--edge-rail-row));
+}
+html[dir='rtl']
+  body.panels-edge-right:not(.mobile-shell):not(.cockpit-mode)
+  #right-context-rail
+  > :not(.gev-panel-rail) {
+  transform: translate(
+    calc(-1 * var(--panel-rail-clearance, 48px)),
+    var(--edge-rail-row)
+  );
+}

style.css

@@ -45,5 +45,9 @@
 @import './src/ui/styles/rtl.css';
 @import './src/ui/styles/mobile-shell.css';
 @import './src/ui/styles/annotations.css';
+@import './src/ui/styles/rail-edge.css';
+@import './src/ui/styles/rail-split.css';
+@import './src/ui/styles/left-tools.css';
+@import './src/ui/styles/panel-edge.css';
 @import './src/ui/styles/ai-chat.css';
 @import './src/ui/styles/cyber.css';