diff --git a/app/client/components/GristDoc.ts b/app/client/components/GristDoc.ts
index c615bcf6..40b8c72b 100644
--- a/app/client/components/GristDoc.ts
+++ b/app/client/components/GristDoc.ts
@@ -355,7 +355,7 @@ export class GristDoc extends DisposableWithEvents {
     this.autoDispose(subscribe(urlState().state, async (_use, state) => {
       // Only start a tour or tutorial when the full interface is showing, i.e. not when in
       // embedded mode.
-      if (state.params?.style === 'light') {
+      if (state.params?.style === 'singlePage') {
         return;
       }
 
diff --git a/app/client/models/AppModel.ts b/app/client/models/AppModel.ts
index abd2b44c..3de1c9c6 100644
--- a/app/client/models/AppModel.ts
+++ b/app/client/models/AppModel.ts
@@ -19,7 +19,7 @@ import {LocalPlugin} from 'app/common/plugin';
 import {DismissedPopup, DismissedReminder, UserPrefs} from 'app/common/Prefs';
 import {isOwner, isOwnerOrEditor} from 'app/common/roles';
 import {getTagManagerScript} from 'app/common/tagManager';
-import {getDefaultThemePrefs, Theme, ThemeAppearance, ThemeColors, ThemePrefs,
+import {getDefaultThemePrefs, Theme, ThemeColors, ThemePrefs,
         ThemePrefsChecker} from 'app/common/ThemePrefs';
 import {getThemeColors} from 'app/common/Themes';
 import {getGristConfig} from 'app/common/urlUtils';
@@ -450,14 +450,26 @@ export class AppModelImpl extends Disposable implements AppModel {
   private _getCurrentThemeObs() {
     return Computed.create(this, this.themePrefs, prefersDarkModeObs(),
       (_use, themePrefs, prefersDarkMode) => {
-        let appearance: ThemeAppearance;
-        if (!themePrefs.syncWithOS) {
-          appearance = themePrefs.appearance;
-        } else {
+        let {appearance, syncWithOS} = themePrefs;
+
+        const urlParams = urlState().state.get().params;
+        if (urlParams?.themeAppearance) {
+          appearance = urlParams?.themeAppearance;
+        }
+
+        if (urlParams?.themeSyncWithOs !== undefined) {
+          syncWithOS = urlParams?.themeSyncWithOs;
+        }
+
+        if (syncWithOS) {
           appearance = prefersDarkMode ? 'dark' : 'light';
         }
 
-        const nameOrColors = themePrefs.colors[appearance];
+        let nameOrColors = themePrefs.colors[appearance];
+        if (urlParams?.themeName) {
+          nameOrColors = urlParams?.themeName;
+        }
+
         let colors: ThemeColors;
         if (typeof nameOrColors === 'string') {
           colors = getThemeColors(nameOrColors);
diff --git a/app/client/ui/PagePanels.ts b/app/client/ui/PagePanels.ts
index a565c8e2..bfb4ae2d 100644
--- a/app/client/ui/PagePanels.ts
+++ b/app/client/ui/PagePanels.ts
@@ -392,7 +392,7 @@ const cssPageContainer = styled(cssVBox, `
       padding-bottom: ${bottomFooterHeightPx}px;
       min-width: 240px;
     }
-    .interface-light & {
+    .interface-singlePage & {
       padding-bottom: 0;
     }
   }
@@ -434,7 +434,7 @@ export const cssLeftPane = styled(cssVBox, `
       display: none;
     }
   }
-  .interface-light & {
+  .interface-singlePage & {
     display: none;
   }
   &-overlap {
@@ -501,7 +501,7 @@ const cssRightPane = styled(cssVBox, `
       display: none;
     }
   }
-  .interface-light & {
+  .interface-singlePage & {
     display: none;
   }
 `);
@@ -519,7 +519,7 @@ const cssHeader = styled('div', `
     }
   }
 
-  .interface-light & {
+  .interface-singlePage & {
     display: none;
   }
 `);
@@ -556,7 +556,7 @@ const cssBottomFooter = styled ('div', `
       display: none;
     }
   }
-  .interface-light & {
+  .interface-singlePage & {
     display: none;
   }
 `);
diff --git a/app/client/ui/ViewLayoutMenu.ts b/app/client/ui/ViewLayoutMenu.ts
index 67a60ec4..4e60490b 100644
--- a/app/client/ui/ViewLayoutMenu.ts
+++ b/app/client/ui/ViewLayoutMenu.ts
@@ -36,7 +36,7 @@ export function makeViewLayoutMenu(viewSection: ViewSectionRec, isReadonly: bool
   ];
 
   const viewRec = viewSection.view();
-  const isLight = urlState().state.get().params?.style === 'light';
+  const isSinglePage = urlState().state.get().params?.style === 'singlePage';
 
   const sectionId = viewSection.table.peek().rawViewSectionRef.peek();
   const anchorUrlState = viewInstance.getAnchorLinkForSection(sectionId);
@@ -57,7 +57,7 @@ export function makeViewLayoutMenu(viewSection: ViewSectionRec, isReadonly: bool
 
   const showRawData = (use: UseCB) => {
     return !use(viewSection.isRaw)// Don't show raw data if we're already in raw data.
-        && !isLight // Don't show raw data in light mode.
+        && !isSinglePage // Don't show raw data in single page mode.
            ;
   };
 
@@ -84,7 +84,7 @@ export function makeViewLayoutMenu(viewSection: ViewSectionRec, isReadonly: bool
       menuItemCmd(allCommands.editLayout, t("Edit Card Layout"),
         dom.cls('disabled', isReadonly))),
 
-    dom.maybe(!isLight, () => [
+    dom.maybe(!isSinglePage, () => [
       menuDivider(),
       menuItemCmd(allCommands.viewTabOpen, t("Widget options"), testId('widget-options')),
       menuItemCmd(allCommands.sortFilterTabOpen, t("Advanced Sort & Filter")),
@@ -111,12 +111,12 @@ export function makeViewLayoutMenu(viewSection: ViewSectionRec, isReadonly: bool
  */
 export function makeCollapsedLayoutMenu(viewSection: ViewSectionRec, gristDoc: GristDoc) {
   const isReadonly = gristDoc.isReadonly.get();
-  const isLight = urlState().state.get().params?.style === 'light';
+  const isSinglePage = urlState().state.get().params?.style === 'singlePage';
   const sectionId = viewSection.table.peek().rawViewSectionRef.peek();
   const anchorUrlState = { hash: { sectionId, popup: true } };
   const rawUrl = urlState().makeUrl(anchorUrlState);
   return [
-    dom.maybe((use) => !use(viewSection.isRaw) && !isLight && !use(gristDoc.maximizedSectionId),
+    dom.maybe((use) => !use(viewSection.isRaw) && !isSinglePage && !use(gristDoc.maximizedSectionId),
       () => menuItemLink(
         { href: rawUrl}, t("Show raw data"), testId('show-raw-data'),
         dom.on('click', (ev) => {
diff --git a/app/common/ThemePrefs.ts b/app/common/ThemePrefs.ts
index 308fe79b..aee78492 100644
--- a/app/common/ThemePrefs.ts
+++ b/app/common/ThemePrefs.ts
@@ -526,6 +526,8 @@ export interface ThemeColors {
 }
 
 export const ThemePrefsChecker = createCheckers(ThemePrefsTI).ThemePrefs as CheckerT<ThemePrefs>;
+export const ThemeAppearanceChecker = createCheckers(ThemePrefsTI).ThemeAppearance as CheckerT<ThemeAppearance>;
+export const ThemeNameChecker = createCheckers(ThemePrefsTI).ThemeName as CheckerT<ThemeName>;
 
 export function getDefaultThemePrefs(): ThemePrefs {
   return {
diff --git a/app/common/gristUrls.ts b/app/common/gristUrls.ts
index 2af7dae7..e7541322 100644
--- a/app/common/gristUrls.ts
+++ b/app/common/gristUrls.ts
@@ -10,6 +10,7 @@ import {getGristConfig} from 'app/common/urlUtils';
 import {Document} from 'app/common/UserAPI';
 import clone = require('lodash/clone');
 import pickBy = require('lodash/pickBy');
+import {ThemeAppearance, ThemeAppearanceChecker, ThemeName, ThemeNameChecker} from './ThemePrefs';
 
 export const SpecialDocPage = StringUnion('code', 'acl', 'data', 'GristDocTour', 'settings', 'webhook');
 type SpecialDocPage = typeof SpecialDocPage.type;
@@ -44,8 +45,8 @@ export type LoginPage = typeof LoginPage.type;
 export const SupportGristPage = StringUnion('support-grist');
 export type SupportGristPage = typeof SupportGristPage.type;
 
-// Overall UI style.  "full" is normal, "light" is a single page focused, panels hidden experience.
-export const InterfaceStyle = StringUnion('light', 'full');
+// Overall UI style.  "full" is normal, "singlePage" is a single page focused, panels hidden experience.
+export const InterfaceStyle = StringUnion('singlePage', 'full');
 export type InterfaceStyle = typeof InterfaceStyle.type;
 
 // Default subdomain for home api service if not otherwise specified.
@@ -126,6 +127,9 @@ export interface IGristUrlState {
     compare?: string;
     linkParameters?: Record<string, string>;  // Parameters to pass as 'user.Link' in granular ACLs.
                                               // Encoded in URL as query params with extra '_' suffix.
+    themeSyncWithOs?: boolean;
+    themeAppearance?: ThemeAppearance;
+    themeName?: ThemeName;
   };
   hash?: HashLink;   // if present, this specifies an individual row within a section of a page.
 }
@@ -392,15 +396,40 @@ export function decodeUrl(gristConfig: Partial<GristLoadConfig>, location: Locat
   }
 
   if (sp.has('style')) {
-    state.params!.style = InterfaceStyle.parse(sp.get('style'));
+    let style = sp.get('style');
+    if (style === 'light') {
+      style = 'singlePage';
+    }
+
+    state.params!.style = InterfaceStyle.parse(style);
   }
   if (sp.has('embed')) {
     const embed = state.params!.embed = isAffirmative(sp.get('embed'));
     // Turn view mode on if no mode has been specified, and not a fork.
     if (embed && !state.mode && !state.fork) { state.mode = 'view'; }
-    // Turn on light style if no style has been specified.
-    if (embed && !state.params!.style) { state.params!.style = 'light'; }
+    // Turn on single page style if no style has been specified.
+    if (embed && !state.params!.style) { state.params!.style = 'singlePage'; }
+  }
+
+  // Theme overrides
+  if (sp.has('themeSyncWithOs')) {
+    state.params!.themeSyncWithOs = isAffirmative(sp.get('themeSyncWithOs'));
   }
+
+  if (sp.has('themeAppearance')) {
+    const appearance = sp.get('themeAppearance');
+    if (ThemeAppearanceChecker.strictTest(appearance)) {
+      state.params!.themeAppearance = appearance;
+    }
+  }
+
+  if (sp.has('themeName')) {
+    const themeName = sp.get('themeName');
+    if (ThemeNameChecker.strictTest(themeName)) {
+      state.params!.themeName = themeName;
+    }
+  }
+
   if (sp.has('compare')) {
     state.params!.compare = sp.get('compare')!;
   }
diff --git a/test/client/models/gristUrlState.ts b/test/client/models/gristUrlState.ts
index 67c31dda..04d7dae3 100644
--- a/test/client/models/gristUrlState.ts
+++ b/test/client/models/gristUrlState.ts
@@ -287,8 +287,8 @@ describe('gristUrlState', function() {
   it('should support an update function to pushUrl and makeUrl', async function() {
     mockWindow.location = new URL('https://bar.example.com/doc/DOC/p/5') as unknown as Location;
     const state = UrlState.create(null, mockWindow, prod) as UrlState<IGristUrlState>;
-    await state.pushUrl({params: {style: 'light', linkParameters: {foo: 'A', bar: 'B'}}});
-    assert.equal(mockWindow.location.href, 'https://bar.example.com/doc/DOC/p/5?style=light&foo_=A&bar_=B');
+    await state.pushUrl({params: {style: 'singlePage', linkParameters: {foo: 'A', bar: 'B'}}});
+    assert.equal(mockWindow.location.href, 'https://bar.example.com/doc/DOC/p/5?style=singlePage&foo_=A&bar_=B');
     state.loadState();  // changing linkParameters requires a page reload
     assert.equal(state.makeUrl((prevState) => merge({}, prevState, {params: {style: 'full'}})),
       'https://bar.example.com/doc/DOC/p/5?style=full&foo_=A&bar_=B');
diff --git a/test/common/gristUrls.ts b/test/common/gristUrls.ts
index fad0dbcb..54e09b00 100644
--- a/test/common/gristUrls.ts
+++ b/test/common/gristUrls.ts
@@ -1,8 +1,52 @@
-import {parseFirstUrlPart} from 'app/common/gristUrls';
+import {decodeUrl, IGristUrlState, parseFirstUrlPart} from 'app/common/gristUrls';
 import {assert} from 'chai';
 
 describe('gristUrls', function() {
 
+  function assertUrlDecode(url: string, expected: Partial<IGristUrlState>) {
+    const actual = decodeUrl({}, new URL(url));
+
+    for (const property in expected) {
+      const expectedValue = expected[property as keyof IGristUrlState];
+      const actualValue = actual[property as keyof IGristUrlState];
+
+      assert.deepEqual(actualValue, expectedValue);
+    }
+  }
+
+  describe('encodeUrl', function() {
+    it('should detect theme appearance override', function() {
+      assertUrlDecode(
+        'http://localhost/?themeAppearance=light',
+        {params: {themeAppearance: 'light'}},
+      );
+
+      assertUrlDecode(
+        'http://localhost/?themeAppearance=dark',
+        {params: {themeAppearance: 'dark'}},
+      );
+    });
+
+    it('should detect theme sync with os override', function() {
+      assertUrlDecode(
+        'http://localhost/?themeSyncWithOs=true',
+        {params: {themeSyncWithOs: true}},
+      );
+    });
+
+    it('should detect theme name override', function() {
+      assertUrlDecode(
+        'http://localhost/?themeName=GristLight',
+        {params: {themeName: 'GristLight'}},
+      );
+
+      assertUrlDecode(
+        'http://localhost/?themeName=GristDark',
+        {params: {themeName: 'GristDark'}},
+      );
+    });
+  });
+
   describe('parseFirstUrlPart', function() {
     it('should strip out matching tag', function() {
       assert.deepEqual(parseFirstUrlPart('o', '/o/foo/bar?x#y'), {value: 'foo', path: '/bar?x#y'});
diff --git a/test/nbrowser/RawData.ts b/test/nbrowser/RawData.ts
index c1749f6c..091c90f2 100644
--- a/test/nbrowser/RawData.ts
+++ b/test/nbrowser/RawData.ts
@@ -675,7 +675,7 @@ async function openMenu(tableId: string) {
 }
 
 async function waitForRawData() {
-  await driver.findWait('.test-raw-data-list', 1000);
+  await driver.findWait('.test-raw-data-list', 2000);
   await gu.waitForServer();
 }