diff --git a/DESIGN.md b/DESIGN.md
index a46aa11a..015304cc 100644
--- a/DESIGN.md
+++ b/DESIGN.md
@@ -39,8 +39,8 @@ chrome competing with additions, deletions, syntax, or selected lines.
 ## Sources of truth
 
 - `apps/web/src/tokens.css`: semantic colors, spacing, geometry, elevation,
-  responsive gutters, light/dark equivalents, and Omarchy theme palettes.
-- `apps/web/src/theme.ts`: the theme registry (id, label, group, mode and
+  responsive gutters, light/dark equivalents, and theme palettes.
+- `apps/web/src/theme.ts`: the theme registry (id, label, kind, mode and
   matching code theme).
 - `apps/web/src/typography.css`: fonts, text/icon sizes, weights, line heights.
 - `apps/web/src/style.css`: Tailwind entry point, shadcn theme bridge, shell,
@@ -99,7 +99,7 @@ token that already has a utility is rejected. 2px (`*-0.5`) steps are optical
 insets reserved for `components/`.
 
 `[data-theme]` always carries the resolved light/dark mode; the Tailwind
-`dark` variant and Pierre's `themeType` read it. Omarchy themes additionally set
+`dark` variant and Pierre's `themeType` read it. Palette themes additionally set
 `[data-palette]`, whose `tokens.css` block remaps every semantic color role, so
 components never branch on a theme. Do not add independent theme state. Tailwind Preflight and utility use must not override Pierre's
 measured elements or replace the application tokens with framework defaults.
@@ -145,15 +145,15 @@ measured elements or replace the application tokens with framework defaults.
   the browser or whole machine. Keep that scope explicit in the status popup.
 - Pierre owns syntax colors, changed-line fills, word highlights, line selection,
   and code-theme surfaces. App status tokens govern the surrounding UI only.
-  Exception: Omarchy palettes without a bundled Shiki theme render code through
+  Exception: palettes without a bundled Shiki theme render code through
   Pierre's CSS-variable theme (`diffx-palette`); their `tokens.css` blocks set
   `--diffs-token-*`/`--diffs-ansi-*` and point Pierre's addition, deletion and
   modified color overrides at `--success`, `--error` and `--warning`.
 
 ### Themes
 
-- Settings offers three Diffx themes (System, Light, Dark) and the 22 themes on
-  omarchy.org. Each Omarchy theme has a fixed mode. The choice is saved per
+- Settings offers three base themes (System, Light, Dark) and 22 palette
+  themes. Each palette theme has a fixed mode. The choice is saved per
   browser (`theme-v2`); `index.html` applies it before the app renders and keeps
   its palette id lists synchronized with `theme.ts`.
 - Palettes keep each theme's background, foreground and accent identity, then
@@ -344,8 +344,8 @@ such detail into a token. New layout spacing must use the scale.
   Add future system details as further sections in the same popover.
   Settings follows it at the trailing edge: an icon-only compact ghost gear
   that opens a `--surface-raised` popover titled “Settings”, capped at 24rem
-  and scrolling internally. Its Theme section is a choice list grouped under
-  “Diffx” and “Omarchy”; rows show a theme swatch, the name and a check on the
+  and scrolling internally. Its Theme section is one flat choice list, base
+  themes first; rows show a theme swatch, the name and a check on the
   current theme. Clicking or arrowing applies and saves immediately; there is
   no hover preview. Add future browser preferences as further sections.
 - The diff display toolbar uses `--panel`, matching the header and status bar.
@@ -444,7 +444,7 @@ with a semantic variant instead of overriding it.
 | Search or filter input                 | `search-field`                                                                                                                           |
 | Text input, select, textarea, checkbox | `ui/input`, `ui/select`, `ui/textarea`, `ui/checkbox`                                                                                    |
 | Tree, nav or picker row                | `list-row` (sans/mono font, depth, `option`)                                                                                             |
-| Single choice among rows (themes)      | `choice-list` (groups, check on the chosen row), `theme-swatch`                                                                          |
+| Single choice among rows (themes)      | `choice-list` (check on the chosen row), `theme-swatch`                                                                                  |
 | Panel title row                        | `panel-header`; tabs in `ui/tabs`                                                                                                        |
 | Collapsible sidebar section            | `collapsible-section`, `disclosure` chevron                                                                                              |
 | Count, status label, status dot        | `count-badge`, `ui/badge` (status tones), `status-dot`                                                                                   |
diff --git a/apps/web/index.html b/apps/web/index.html
index bfa77e49..20302949 100644
--- a/apps/web/index.html
+++ b/apps/web/index.html
@@ -6,7 +6,7 @@
     <meta name="color-scheme" content="light dark" />
     <script>
       (() => {
-        // Keep these Omarchy ids synchronized with THEMES in src/theme.ts.
+        // Keep these palette ids synchronized with THEMES in src/theme.ts.
         const lightPalettes = [
           "catppuccin-latte",
           "flexoki-light",
diff --git a/apps/web/src/SettingsButton.tsx b/apps/web/src/SettingsButton.tsx
index 8ec15cc7..b6a8ba34 100644
--- a/apps/web/src/SettingsButton.tsx
+++ b/apps/web/src/SettingsButton.tsx
@@ -1,9 +1,5 @@
 import { SettingsIcon } from "lucide-react";
-import {
-  ChoiceList,
-  ChoiceListGroup,
-  ChoiceListItem,
-} from "@/components/choice-list";
+import { ChoiceList, ChoiceListItem } from "@/components/choice-list";
 import { IconButton } from "@/components/icon-button";
 import {
   Popover,
@@ -17,11 +13,6 @@ import { ThemeSwatch } from "@/components/theme-swatch";
 import { useAppearance } from "./appearance-context.tsx";
 import { readThemePreference, swatchPalette, THEMES } from "./theme.ts";
 
-const groups = [
-  { group: "diffx", label: "Diffx" },
-  { group: "omarchy", label: "Omarchy" },
-] as const;
-
 /** Browser-saved preferences, opened from the status bar's trailing edge. */
 export function SettingsButton() {
   const { themePreference, setThemePreference } = useAppearance();
@@ -46,23 +37,17 @@ export function SettingsButton() {
               setThemePreference(readThemePreference(value))
             }
           >
-            {groups.map(({ group, label }) => (
-              <ChoiceListGroup key={group} label={label}>
-                {THEMES.filter((theme) => theme.group === group).map(
-                  (theme) => (
-                    <ChoiceListItem key={theme.id} value={theme.id}>
-                      <ThemeSwatch
-                        palettes={
-                          theme.id === "system"
-                            ? ["diffx-light", "diffx-dark"]
-                            : [swatchPalette(theme.id)]
-                        }
-                      />
-                      {theme.label}
-                    </ChoiceListItem>
-                  ),
-                )}
-              </ChoiceListGroup>
+            {THEMES.map((theme) => (
+              <ChoiceListItem key={theme.id} value={theme.id}>
+                <ThemeSwatch
+                  palettes={
+                    theme.id === "system"
+                      ? ["diffx-light", "diffx-dark"]
+                      : [swatchPalette(theme.id)]
+                  }
+                />
+                {theme.label}
+              </ChoiceListItem>
             ))}
           </ChoiceList>
         </PopoverSection>
diff --git a/apps/web/src/components/choice-list.tsx b/apps/web/src/components/choice-list.tsx
index ef8df9af..a710794d 100644
--- a/apps/web/src/components/choice-list.tsx
+++ b/apps/web/src/components/choice-list.tsx
@@ -1,7 +1,7 @@
 import { Radio } from "@base-ui/react/radio";
 import { RadioGroup } from "@base-ui/react/radio-group";
 import { CheckIcon } from "lucide-react";
-import { useId, type ReactNode } from "react";
+import type { ReactNode } from "react";
 import { ListRow } from "@/components/list-row";
 import { cn } from "@/lib/utils";
 
@@ -19,30 +19,6 @@ function ChoiceList({ className, ...props }: RadioGroup.Props<string>) {
   );
 }
 
-/** Rows under a quiet heading that names the group for assistive tech. */
-function ChoiceListGroup({
-  label,
-  children,
-}: {
-  label: string;
-  children: ReactNode;
-}) {
-  const labelId = useId();
-  return (
-    <div
-      data-slot="choice-list-group"
-      role="group"
-      aria-labelledby={labelId}
-      className="flex flex-col gap-0.5"
-    >
-      <div id={labelId} className="px-1 pt-2 pb-1 text-xs text-muted">
-        {label}
-      </div>
-      {children}
-    </div>
-  );
-}
-
 function ChoiceListItem({
   value,
   children,
@@ -60,4 +36,4 @@ function ChoiceListItem({
   );
 }
 
-export { ChoiceList, ChoiceListGroup, ChoiceListItem };
+export { ChoiceList, ChoiceListItem };
diff --git a/apps/web/src/gallery/Gallery.tsx b/apps/web/src/gallery/Gallery.tsx
index 4a563a4c..92b510d7 100644
--- a/apps/web/src/gallery/Gallery.tsx
+++ b/apps/web/src/gallery/Gallery.tsx
@@ -59,11 +59,7 @@ import {
   TooltipContent,
   TooltipTrigger,
 } from "@/components/ui/tooltip";
-import {
-  ChoiceList,
-  ChoiceListGroup,
-  ChoiceListItem,
-} from "@/components/choice-list";
+import { ChoiceList, ChoiceListItem } from "@/components/choice-list";
 import { CollapsibleSection } from "@/components/collapsible-section";
 import { ConfirmDialog } from "@/components/confirm-dialog";
 import { ContextIcon } from "@/components/context-icon";
@@ -490,26 +486,22 @@ function Components() {
           defaultValue="dark"
           className="w-full max-w-(--drawer-width)"
         >
-          <ChoiceListGroup label="Diffx">
-            <ChoiceListItem value="system">
-              <ThemeSwatch palettes={["diffx-light", "diffx-dark"]} />
-              System
-            </ChoiceListItem>
-            <ChoiceListItem value="dark">
-              <ThemeSwatch palettes={["diffx-dark"]} />
-              Dark
-            </ChoiceListItem>
-          </ChoiceListGroup>
-          <ChoiceListGroup label="Omarchy">
-            <ChoiceListItem value="tokyo-night">
-              <ThemeSwatch palettes={["tokyo-night"]} />
-              Tokyo Night
-            </ChoiceListItem>
-            <ChoiceListItem value="flexoki-light">
-              <ThemeSwatch palettes={["flexoki-light"]} />
-              Flexoki Light
-            </ChoiceListItem>
-          </ChoiceListGroup>
+          <ChoiceListItem value="system">
+            <ThemeSwatch palettes={["diffx-light", "diffx-dark"]} />
+            System
+          </ChoiceListItem>
+          <ChoiceListItem value="dark">
+            <ThemeSwatch palettes={["diffx-dark"]} />
+            Dark
+          </ChoiceListItem>
+          <ChoiceListItem value="tokyo-night">
+            <ThemeSwatch palettes={["tokyo-night"]} />
+            Tokyo Night
+          </ChoiceListItem>
+          <ChoiceListItem value="flexoki-light">
+            <ThemeSwatch palettes={["flexoki-light"]} />
+            Flexoki Light
+          </ChoiceListItem>
         </ChoiceList>
       </Section>
 
diff --git a/apps/web/src/theme.ts b/apps/web/src/theme.ts
index 65b8992a..fef7f37e 100644
--- a/apps/web/src/theme.ts
+++ b/apps/web/src/theme.ts
@@ -11,7 +11,7 @@ export const PALETTE_CODE_THEME = "diffx-palette";
 type ThemeDefinition = {
   id: string;
   label: string;
-  group: "diffx" | "omarchy";
+  kind: "base" | "palette";
   mode: ResolvedTheme | "system";
   /** Code theme used when the code theme matches the app theme. */
   code: ThemesType;
@@ -26,168 +26,167 @@ function bundled(name: string): ThemesType {
   return { light: name, dark: name };
 }
 
-/** Omarchy palettes: https://github.com/basecamp/omarchy (MIT). */
 export const THEMES = [
   {
     id: "system",
     label: "System",
-    group: "diffx",
+    kind: "base",
     mode: "system",
     code: pierre,
   },
-  { id: "light", label: "Light", group: "diffx", mode: "light", code: pierre },
-  { id: "dark", label: "Dark", group: "diffx", mode: "dark", code: pierre },
+  { id: "light", label: "Light", kind: "base", mode: "light", code: pierre },
+  { id: "dark", label: "Dark", kind: "base", mode: "dark", code: pierre },
   {
     id: "catppuccin",
     label: "Catppuccin",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: bundled("catppuccin-mocha"),
   },
   {
     id: "catppuccin-latte",
     label: "Catppuccin Latte",
-    group: "omarchy",
+    kind: "palette",
     mode: "light",
     code: bundled("catppuccin-latte"),
   },
   {
     id: "ethereal",
     label: "Ethereal",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: palette,
   },
   {
     id: "everforest",
     label: "Everforest",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: bundled("everforest-dark"),
   },
   {
     id: "flexoki-light",
     label: "Flexoki Light",
-    group: "omarchy",
+    kind: "palette",
     mode: "light",
     code: palette,
   },
   {
     id: "gruvbox",
     label: "Gruvbox",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: bundled("gruvbox-dark-medium"),
   },
   {
     id: "hackerman",
     label: "Hackerman",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: palette,
   },
   {
     id: "kanagawa",
     label: "Kanagawa",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: bundled("kanagawa-wave"),
   },
   {
     id: "last-horizon",
     label: "Last Horizon",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: palette,
   },
   {
     id: "lumon",
     label: "Lumon",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: palette,
   },
   {
     id: "lupine",
     label: "Lupine",
-    group: "omarchy",
+    kind: "palette",
     mode: "light",
     code: palette,
   },
   {
     id: "matte-black",
     label: "Matte Black",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: palette,
   },
   {
     id: "miasma",
     label: "Miasma",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: palette,
   },
   {
     id: "nord",
     label: "Nord",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: bundled("nord"),
   },
   {
     id: "osaka-jade",
     label: "Osaka Jade",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: palette,
   },
   {
     id: "retro-82",
     label: "Retro 82",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: palette,
   },
   {
     id: "ristretto",
     label: "Ristretto",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: palette,
   },
   {
     id: "rose-pine",
     label: "Rosé Pine",
-    group: "omarchy",
+    kind: "palette",
     mode: "light",
     code: bundled("rose-pine-dawn"),
   },
   {
     id: "solitude",
     label: "Solitude",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: palette,
   },
   {
     id: "tokyo-night",
     label: "Tokyo Night",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: bundled("tokyo-night"),
   },
   {
     id: "vantablack",
     label: "Vantablack",
-    group: "omarchy",
+    kind: "palette",
     mode: "dark",
     code: palette,
   },
   {
     id: "white",
     label: "White",
-    group: "omarchy",
+    kind: "palette",
     mode: "light",
     code: palette,
   },
@@ -218,18 +217,18 @@ export function resolveTheme(
   return systemDark ? "dark" : "light";
 }
 
-/** The `data-palette` id for Omarchy themes; Diffx themes use base tokens. */
+/** The `data-palette` id for palette themes; base themes use base tokens. */
 export function themePalette(preference: ThemePreference): string | undefined {
   const theme = themeFor(preference);
-  return theme.group === "omarchy" ? theme.id : undefined;
+  return theme.kind === "palette" ? theme.id : undefined;
 }
 
-/** The swatch palette: Diffx themes preview their light/dark tokens. */
+/** The swatch palette: base themes preview their light/dark tokens. */
 export function swatchPalette(
   preference: Exclude<ThemePreference, "system">,
 ): string {
   const theme = themeFor(preference);
-  return theme.group === "omarchy" ? theme.id : `diffx-${theme.mode}`;
+  return theme.kind === "palette" ? theme.id : `diffx-${theme.mode}`;
 }
 
 export function themeCode(preference: ThemePreference): ThemesType {
diff --git a/apps/web/src/tokens.css b/apps/web/src/tokens.css
index cf4aba1d..32a9591c 100644
--- a/apps/web/src/tokens.css
+++ b/apps/web/src/tokens.css
@@ -134,11 +134,8 @@
   --file-config: #bc9de2;
 }
 
-/* Omarchy palettes: adapted from Omarchy themes/<id>/colors.toml.
-   Omarchy is MIT licensed: https://github.com/basecamp/omarchy
-   Source commit: cbd44ba1d649c334f3c9dcd8628c5c390524d344
-   Values are tuned for WCAG AA against Diffx surfaces, so some differ from
-   the source palettes. */
+/* Palette themes: values are tuned for WCAG AA against Diffx surfaces, so
+   some differ from the source palettes. */
 :root[data-palette="catppuccin"],
 [data-palette="catppuccin"] {
   color-scheme: dark;
diff --git a/apps/web/test/browser/app.spec.ts b/apps/web/test/browser/app.spec.ts
index 021d3544..2527bcf0 100644
--- a/apps/web/test/browser/app.spec.ts
+++ b/apps/web/test/browser/app.spec.ts
@@ -1552,7 +1552,7 @@ test("inline comments use a distinct structured surface while sidebar comments r
   expect(copyHoverBackground).not.toBe(copyRestingBackground);
 });
 
-test("settings theme picker follows system, applies Omarchy palettes and persists", async ({
+test("settings theme picker follows system, applies palettes and persists", async ({
   page,
 }) => {
   await page.emulateMedia({ colorScheme: "dark" });
@@ -1576,8 +1576,8 @@ test("settings theme picker follows system, applies Omarchy palettes and persist
   await settings.click();
   const themes = page.getByRole("radiogroup", { name: "Theme" });
   await expect(themes.getByRole("radio")).toHaveCount(25);
-  await expect(themes.getByRole("group", { name: "Diffx" })).toBeVisible();
-  await expect(themes.getByRole("group", { name: "Omarchy" })).toBeVisible();
+  // One flat list: no group headings.
+  await expect(themes.getByRole("group")).toHaveCount(0);
   await expect(
     themes.getByRole("radio", { name: "System", exact: true }),
   ).toBeChecked();
diff --git a/apps/web/test/gallery/goldens/choices-dark-linux.png b/apps/web/test/gallery/goldens/choices-dark-linux.png
index cea8622b..b55c9e73 100644
Binary files a/apps/web/test/gallery/goldens/choices-dark-linux.png and b/apps/web/test/gallery/goldens/choices-dark-linux.png differ
diff --git a/apps/web/test/gallery/goldens/choices-light-linux.png b/apps/web/test/gallery/goldens/choices-light-linux.png
index b223110a..496e9948 100644
Binary files a/apps/web/test/gallery/goldens/choices-light-linux.png and b/apps/web/test/gallery/goldens/choices-light-linux.png differ
diff --git a/apps/web/test/gallery/goldens/states-dark-linux.png b/apps/web/test/gallery/goldens/states-dark-linux.png
index b113dd58..84c431af 100644
Binary files a/apps/web/test/gallery/goldens/states-dark-linux.png and b/apps/web/test/gallery/goldens/states-dark-linux.png differ
diff --git a/apps/web/test/gallery/goldens/states-light-linux.png b/apps/web/test/gallery/goldens/states-light-linux.png
index 6be971a8..bda0605f 100644
Binary files a/apps/web/test/gallery/goldens/states-light-linux.png and b/apps/web/test/gallery/goldens/states-light-linux.png differ
diff --git a/apps/web/test/theme.test.ts b/apps/web/test/theme.test.ts
index 095aee5a..afb4a6be 100644
--- a/apps/web/test/theme.test.ts
+++ b/apps/web/test/theme.test.ts
@@ -24,7 +24,7 @@ test("system theme resolves from the operating system", () => {
   assert.equal(resolveTheme("dark", false), "dark");
 });
 
-test("Omarchy themes keep their fixed mode and palette", () => {
+test("palette themes keep their fixed mode and palette", () => {
   assert.equal(readThemePreference("tokyo-night"), "tokyo-night");
   assert.equal(readThemePreference("starship"), "system");
   assert.equal(resolveTheme("tokyo-night", false), "dark");
@@ -34,23 +34,23 @@ test("Omarchy themes keep their fixed mode and palette", () => {
   assert.equal(themePalette("system"), undefined);
 });
 
-test("swatches preview Diffx themes through their base palettes", () => {
+test("swatches preview base themes through their base palettes", () => {
   assert.equal(swatchPalette("light"), "diffx-light");
   assert.equal(swatchPalette("dark"), "diffx-dark");
   assert.equal(swatchPalette("nord"), "nord");
 });
 
-test("theme registry lists Diffx themes and the 22 Omarchy themes", () => {
+test("theme registry lists base themes and the 22 palette themes", () => {
   const ids = THEMES.map((theme) => theme.id);
   assert.equal(new Set(ids).size, ids.length);
   assert.deepEqual(
-    THEMES.filter((theme) => theme.group === "diffx").map((theme) => theme.id),
+    THEMES.filter((theme) => theme.kind === "base").map((theme) => theme.id),
     ["system", "light", "dark"],
   );
-  assert.equal(THEMES.filter((theme) => theme.group === "omarchy").length, 22);
+  assert.equal(THEMES.filter((theme) => theme.kind === "palette").length, 22);
 });
 
-test("boot script lists every Omarchy palette with its mode", () => {
+test("boot script lists every palette with its mode", () => {
   const html = readFileSync(new URL("../index.html", import.meta.url), "utf8");
   const listed = (name: string) =>
     [
@@ -60,7 +60,7 @@ test("boot script lists every Omarchy palette with its mode", () => {
     ].map((match) => match[1]);
   const palettes = (mode: string) =>
     THEMES.filter(
-      (theme) => theme.group === "omarchy" && theme.mode === mode,
+      (theme) => theme.kind === "palette" && theme.mode === mode,
     ).map((theme) => theme.id);
   assert.deepEqual(listed("lightPalettes"), palettes("light"));
   assert.deepEqual(listed("darkPalettes"), palettes("dark"));