Add accessible interface font choices

src/main.tsx

@@ -9,9 +9,9 @@ import { isElectron } from "@/lib/electron";
 import { Toaster } from "@/components/sonner";
 import { Auth, getStoredAuth, clearStoredAuth } from "@/auth/Auth";
 import { getUserInfo, getCurrentToken, appReadyPromise } from "@/main-axios";
-import { applyAccentColor, applyFontSize } from "@/lib/theme";
+import { applyAccentColor, applyFontSize, applyUiFont } from "@/lib/theme";
 import { installElectronWheelZoomGuard } from "@/lib/electron-wheel-zoom";
-import type { FontSizeId } from "@/types/ui-types";
+import type { FontSizeId, UiFontId } from "@/types/ui-types";
 import { useServiceWorker } from "@/hooks/use-service-worker";
 import { useTranslation } from "react-i18next";
 import { UiPreferencesProvider } from "@/contexts/UiPreferencesContext";
@@ -202,6 +202,10 @@ function App() {
       "termix-font-size",
     ) as FontSizeId | null;
     applyFontSize(savedSize ?? "md");
+    applyUiFont(
+      (localStorage.getItem("termix-ui-font") as UiFontId | null) ??
+        "jetbrains-mono",
+    );
     return () => {
       if (timerRef.current) clearTimeout(timerRef.current);
     };

src/types/ui-types.ts

@@ -357,6 +357,12 @@ export type ThemeId =
   | "one-dark"
   | "gruvbox";
 export type FontSizeId = "xs" | "sm" | "md" | "lg" | "xl";
+export type UiFontId =
+  | "jetbrains-mono"
+  | "system-sans"
+  | "fira-code"
+  | "source-code-pro"
+  | "caskaydia-cove";
 
 export type ToolsTab =
   "ssh-tools" | "snippets" | "macros" | "history" | "split-screen";

src/ui/AppShell.tsx

@@ -859,6 +859,7 @@ export function AppShell({
             const SNAPSHOT_KEYS = [
               "termix-accent",
               "termix-font-size",
+              "termix-ui-font",
               "i18nextLng",
               "commandAutocomplete",
               "commandPaletteShortcutEnabled",

src/ui/index.css

@@ -55,7 +55,7 @@
 
 @theme inline {
   --font-heading: var(--font-mono);
-  --font-mono: "JetBrains Mono Variable", monospace;
+  --font-mono: var(--font-ui, "JetBrains Mono Variable", monospace);
   --color-accent-brand: var(--accent-brand);
   --color-sidebar-ring: var(--sidebar-ring);
   --color-sidebar-border: var(--sidebar-border);

src/ui/lib/theme.ts

@@ -1,6 +1,7 @@
 import type {
   DashboardCardConfig,
   FontSizeId,
+  UiFontId,
   SplitMode,
 } from "@/types/ui-types";
 
@@ -89,6 +90,40 @@ export function applyFontSize(id: FontSizeId) {
   localStorage.setItem("termix-font-size", id);
 }
 
+export const UI_FONTS: { id: UiFontId; label: string; family: string }[] = [
+  {
+    id: "jetbrains-mono",
+    label: "JetBrains Mono",
+    family: '"JetBrains Mono Variable", monospace',
+  },
+  {
+    id: "system-sans",
+    label: "System Sans",
+    family: "ui-sans-serif, system-ui, sans-serif",
+  },
+  {
+    id: "fira-code",
+    label: "Fira Code",
+    family: '"Fira Code", monospace',
+  },
+  {
+    id: "source-code-pro",
+    label: "Source Code Pro",
+    family: '"Source Code Pro", monospace',
+  },
+  {
+    id: "caskaydia-cove",
+    label: "Caskaydia Cove",
+    family: '"Caskaydia Cove Nerd Font Mono", monospace',
+  },
+];
+
+export function applyUiFont(id: UiFontId) {
+  const font = UI_FONTS.find((candidate) => candidate.id === id) ?? UI_FONTS[0];
+  document.documentElement.style.setProperty("--font-ui", font.family);
+  localStorage.setItem("termix-ui-font", font.id);
+}
+
 export const FOLDER_COLORS = [
   "#ef4444",
   "#f97316",

src/ui/locales/en.json

@@ -4150,6 +4150,8 @@
         "languageLabel": "Language",
         "themeLabel": "Theme",
         "fontSizeLabel": "Font Size",
+        "interfaceFontLabel": "Interface Font",
+        "interfaceFontDescription": "Changes the application interface font. Terminal profiles keep their own font settings.",
         "accentColorLabel": "Accent Color",
         "settingsTerminal": "Terminal",
         "commandAutocomplete": "Command Autocomplete",

src/ui/sidebar/UserProfilePanel.tsx

@@ -77,11 +77,13 @@ import {
   ACCENT_PRESET_COLORS,
   applyAccentColor,
   applyFontSize,
+  applyUiFont,
   FONT_SIZES,
+  UI_FONTS,
 } from "@/lib/theme";
 import type { ApiKey } from "@/main-axios";
 import { useTheme } from "@/components/theme-provider";
-import type { FontSizeId, ThemeId } from "@/types/ui-types";
+import type { FontSizeId, ThemeId, UiFontId } from "@/types/ui-types";
 import { toast } from "sonner";
 import { changeAppLanguage, normalizeLanguageCode } from "@/i18n/i18n";
 import { clearLocalAdaptivePreferences } from "@/lib/local-adaptive-preferences";
@@ -597,6 +599,10 @@ export function UserProfilePanel({
   const [fontSize, setFontSize] = useState<FontSizeId>(
     () => (localStorage.getItem("termix-font-size") as FontSizeId) ?? "md",
   );
+  const [uiFont, setUiFont] = useState<UiFontId>(
+    () =>
+      (localStorage.getItem("termix-ui-font") as UiFontId) ?? "jetbrains-mono",
+  );
   const [language, setLanguage] = useState(() =>
     normalizeLanguageCode(localStorage.getItem("i18nextLng")),
   );
@@ -831,6 +837,7 @@ export function UserProfilePanel({
       const SNAPSHOT_KEYS = [
         "termix-accent",
         "termix-font-size",
+        "termix-ui-font",
         "i18nextLng",
         "commandAutocomplete",
         "commandPaletteShortcutEnabled",
@@ -961,6 +968,8 @@ export function UserProfilePanel({
     setTheme("system");
     setFontSize("md");
     applyFontSize("md");
+    setUiFont("jetbrains-mono");
+    applyUiFont("jetbrains-mono");
     setAccentColor(DEFAULT_ACCENT);
     setCustomColorInput(DEFAULT_ACCENT);
     localStorage.setItem("termix-accent", DEFAULT_ACCENT);
@@ -1047,6 +1056,12 @@ export function UserProfilePanel({
     setFontSize(restoredFontSize);
     applyFontSize(restoredFontSize);
 
+    const restoredUiFont =
+      (restore("termix-ui-font", "jetbrains-mono") as UiFontId) ??
+      "jetbrains-mono";
+    setUiFont(restoredUiFont);
+    applyUiFont(restoredUiFont);
+
     const restoredAccent = restore("termix-accent", "#f59145") ?? "#f59145";
     setAccentColor(restoredAccent);
     setCustomColorInput(restoredAccent);
@@ -1156,6 +1171,11 @@ export function UserProfilePanel({
     if (storageMode === "cloud") saveToCloud({ fontSize: id });
   }
 
+  function handleUiFontChange(id: UiFontId) {
+    setUiFont(id);
+    applyUiFont(id);
+  }
+
   function handleLanguageChange(code: string) {
     void changeAppLanguage(code)
       .then((language) => {
@@ -1723,6 +1743,29 @@ export function UserProfilePanel({
             </div>
           </div>
 
+          <div className="flex flex-col gap-1.5">
+            <span className="text-[10px] font-bold uppercase tracking-widest text-muted-foreground flex items-center gap-1.5">
+              <Type className="size-3" />
+              {t("newUi.sidebar.userProfile.interfaceFontLabel")}
+            </span>
+            <select
+              value={uiFont}
+              onChange={(event) =>
+                handleUiFontChange(event.target.value as UiFontId)
+              }
+              className="px-2.5 py-1.5 text-xs bg-background border border-border text-foreground outline-none focus:ring-1 focus:ring-ring w-full"
+            >
+              {UI_FONTS.map((font) => (
+                <option key={font.id} value={font.id}>
+                  {font.label}
+                </option>
+              ))}
+            </select>
+            <span className="text-[10px] text-muted-foreground">
+              {t("newUi.sidebar.userProfile.interfaceFontDescription")}
+            </span>
+          </div>
+
           <div className="flex flex-col gap-1.5">
             <span className="text-[10px] font-bold uppercase tracking-widest text-muted-foreground flex items-center gap-1.5">
               <Type className="size-3" />

src/ui/tests/lib/ui-font.test.ts

@@ -0,0 +1,24 @@
+import { beforeEach, describe, expect, it } from "vitest";
+import { applyUiFont } from "../../lib/theme";
+
+describe("applyUiFont", () => {
+  beforeEach(() => {
+    localStorage.clear();
+    document.documentElement.style.removeProperty("--font-ui");
+  });
+
+  it("applies and persists a readable system font", () => {
+    applyUiFont("system-sans");
+
+    expect(document.documentElement.style.getPropertyValue("--font-ui")).toBe(
+      "ui-sans-serif, system-ui, sans-serif",
+    );
+    expect(localStorage.getItem("termix-ui-font")).toBe("system-sans");
+  });
+
+  it("falls back to JetBrains Mono for an unknown stored value", () => {
+    applyUiFont("unknown" as never);
+
+    expect(localStorage.getItem("termix-ui-font")).toBe("jetbrains-mono");
+  });
+});