diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 919b1241..0ed8f3d1 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -67,6 +67,9 @@ jobs:
       - name: Check Electron Access Guard
         run: bash scripts/check-electron-access.sh
 
+      - name: Design tokens (engine + no hard-coded colors in UI)
+        run: npm run check:design-tokens
+
   pytest:
     name: Run Python Tests
     runs-on: ubuntu-latest
diff --git a/.lintstagedrc.json b/.lintstagedrc.json
index 3f024a1d..a9efd373 100644
--- a/.lintstagedrc.json
+++ b/.lintstagedrc.json
@@ -1,6 +1,7 @@
 {
   "*.{ts,tsx}": [
     "eslint --fix --no-warn-ignored",
+    "node scripts/check-design-token-usage.mjs",
     "prettier --write",
     "node licenses/update_license.js"
   ],
diff --git a/package.json b/package.json
index f69dfec4..de54d619 100644
--- a/package.json
+++ b/package.json
@@ -44,9 +44,11 @@
     "test:e2e": "vitest run --config vitest.config.ts",
     "test:coverage": "vitest run --coverage",
     "check:i18n": "node scripts/check-i18n-locale-parity.js",
+    "check:design-token-usage": "node scripts/check-design-token-usage.mjs",
+    "check:design-tokens": "npm run verify:theme && npm run check:design-token-usage",
     "verify:theme": "vite-node scripts/verify-theme-tokens.ts",
     "type-check": "tsc -p tsconfig.build.json --noEmit",
-    "lint": "eslint . --no-warn-ignored",
+    "lint": "eslint . --no-warn-ignored && npm run check:design-token-usage",
     "lint:fix": "eslint . --fix --no-warn-ignored",
     "format": "prettier --write \"**/*.{ts,tsx,js,jsx,json,css,md}\"",
     "format:check": "prettier --check \"**/*.{ts,tsx,js,jsx,json,css,md}\"",
diff --git a/scripts/check-design-token-usage.mjs b/scripts/check-design-token-usage.mjs
new file mode 100644
index 00000000..26ae1260
--- /dev/null
+++ b/scripts/check-design-token-usage.mjs
@@ -0,0 +1,196 @@
+// ========= Copyright 2025-2026 @ Eigent.ai All Rights Reserved. =========
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// ========= Copyright 2025-2026 @ Eigent.ai All Rights Reserved. =========
+
+/**
+ * Fails if UI source contains hard-coded colors instead of design tokens
+ * (CSS variables such as var(--ds-...), var(--colors-...), component vars, or
+ * Tailwind classes that map to those vars — not raw #hex / rgb() / hsl()).
+ *
+ * Usage:
+ *   node scripts/check-design-token-usage.mjs
+ *   node scripts/check-design-token-usage.mjs src/a.tsx   # lint-staged (one or more files)
+ *
+ * Exemptions:
+ *   - End-of-line comment: // ds:allow-hardcoded-color
+ *   - scripts/design-token-usage.allowlist — repo-relative paths, one per line (# comments ok)
+ */
+
+import { readFileSync, existsSync, readdirSync, statSync } from 'node:fs';
+import { dirname, join, relative, resolve } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+const REPO_ROOT = resolve(__dirname, '..');
+
+const EXT = new Set(['.ts', '.tsx', '.js', '.jsx']);
+
+const SKIP_PREFIXES = ['src/lib/themeTokens/'];
+
+const SKIP_FILE_RE =
+  /\.(test|spec)\.(ts|tsx|js|jsx)$|vite-env\.d\.ts$|\.stories\.(ts|tsx)$/;
+
+const HEX_RE = /#([0-9a-fA-F]{8}|[0-9a-fA-F]{6}|[0-9a-fA-F]{3})\b/g;
+
+const RGB_NUM_RE = /\brgba?\(\s*[\d.]/;
+const HSL_NUM_RE = /\bhsla?\(\s*[\d.]/;
+
+const ARBITRARY_HEX_RE =
+  /\[[^\]]*#([0-9a-fA-F]{8}|[0-9a-fA-F]{6}|[0-9a-fA-F]{3})\b[^\]]*\]/;
+const ARBITRARY_RGB_RE = /\[[^\]]*rgba?\([^\]]*\]/;
+
+function loadAllowlist() {
+  const path = join(REPO_ROOT, 'scripts/design-token-usage.allowlist');
+  const set = new Set();
+  if (!existsSync(path)) return set;
+  const raw = readFileSync(path, 'utf8');
+  for (const line of raw.split('\n')) {
+    const t = line.trim();
+    if (!t || t.startsWith('#')) continue;
+    set.add(t.replaceAll('\\', '/'));
+  }
+  return set;
+}
+
+function shouldSkipPath(relPosix, allowlist) {
+  const norm = relPosix.replaceAll('\\', '/');
+  if (allowlist.has(norm)) return true;
+  for (const prefix of SKIP_PREFIXES) {
+    if (norm.startsWith(prefix)) return true;
+  }
+  if (SKIP_FILE_RE.test(norm)) return true;
+  return false;
+}
+
+function* walkSrcFiles(dir) {
+  const entries = readdirSync(dir, { withFileTypes: true });
+  for (const e of entries) {
+    const p = join(dir, e.name);
+    if (e.isDirectory()) {
+      if (e.name === 'node_modules' || e.name === 'dist') continue;
+      yield* walkSrcFiles(p);
+    } else {
+      const ext = e.name.slice(e.name.lastIndexOf('.'));
+      if (EXT.has(ext)) yield p;
+    }
+  }
+}
+
+function stripTrailingLineComment(line) {
+  const idx = line.indexOf('//');
+  if (idx === -1) return line;
+  return line.slice(0, idx);
+}
+
+function lineHasExemption(line) {
+  return line.includes('//') && line.includes('ds:allow-hardcoded-color');
+}
+
+function checkLine(rawLine, lineNum, fileRel, out) {
+  if (lineHasExemption(rawLine)) return;
+  const line = stripTrailingLineComment(rawLine);
+
+  if (RGB_NUM_RE.test(line) || HSL_NUM_RE.test(line)) {
+    out.push({
+      file: fileRel,
+      line: lineNum,
+      message:
+        'Use design tokens (e.g. var(--ds-...), Tailwind semantic colors) instead of raw rgb/hsl.',
+      snippet: rawLine.trim(),
+    });
+    return;
+  }
+
+  HEX_RE.lastIndex = 0;
+  let m;
+  while ((m = HEX_RE.exec(line)) !== null) {
+    const start = m.index;
+    const before = line.slice(Math.max(0, start - 4), start);
+    if (/url\s*\(\s*$/i.test(before)) continue;
+    out.push({
+      file: fileRel,
+      line: lineNum,
+      message: `Hard-coded hex "${m[0]}" — use a design token or Tailwind color that maps to var(--...).`,
+      snippet: rawLine.trim(),
+    });
+    return;
+  }
+
+  if (ARBITRARY_HEX_RE.test(line) || ARBITRARY_RGB_RE.test(line)) {
+    out.push({
+      file: fileRel,
+      line: lineNum,
+      message:
+        'Tailwind arbitrary color value ([#...] / [rgb(...)]) — use ds-* or semantic utilities.',
+      snippet: rawLine.trim(),
+    });
+  }
+}
+
+function checkFile(absPath, allowlist) {
+  const rel = relative(REPO_ROOT, absPath);
+  const relPosix = rel.replaceAll('\\', '/');
+  if (shouldSkipPath(relPosix, allowlist)) return [];
+
+  const text = readFileSync(absPath, 'utf8');
+  const lines = text.split(/\r?\n/);
+  const out = [];
+  lines.forEach((ln, i) => checkLine(ln, i + 1, relPosix, out));
+  return out;
+}
+
+function resolveCliFiles(argv) {
+  const files = [];
+  for (const a of argv) {
+    if (a.startsWith('-')) continue;
+    const abs = resolve(REPO_ROOT, a);
+    if (existsSync(abs) && statSync(abs).isFile()) files.push(abs);
+  }
+  return files;
+}
+
+function main() {
+  const allowlist = loadAllowlist();
+  const argv = process.argv.slice(2).filter((a) => a !== '--');
+  const explicit = resolveCliFiles(argv);
+
+  const targets =
+    explicit.length > 0
+      ? explicit
+      : [...walkSrcFiles(join(REPO_ROOT, 'src'))];
+
+  const violations = [];
+  for (const abs of targets) {
+    violations.push(...checkFile(abs, allowlist));
+  }
+
+  if (violations.length === 0) {
+    console.log('check-design-token-usage: OK (no hard-coded colors found).');
+    process.exit(0);
+  }
+
+  console.error('check-design-token-usage: hard-coded colors detected:\n');
+  for (const v of violations) {
+    console.error(`  ${v.file}:${v.line}`);
+    console.error(`    ${v.message}`);
+    console.error(
+      `    ${v.snippet.slice(0, 200)}${v.snippet.length > 200 ? '…' : ''}\n`
+    );
+  }
+  console.error(
+    `Total: ${violations.length} finding(s). Fix or add // ds:allow-hardcoded-color on the line, or list the file in scripts/design-token-usage.allowlist (one path per line).`
+  );
+  process.exit(1);
+}
+
+main();
diff --git a/scripts/design-token-usage.allowlist b/scripts/design-token-usage.allowlist
new file mode 100644
index 00000000..02b34262
--- /dev/null
+++ b/scripts/design-token-usage.allowlist
@@ -0,0 +1,11 @@
+# Whole-file skips for scripts/check-design-token-usage.mjs (run: npm run check:design-token-usage).
+# Prefer design tokens or a line-level // ds:allow-hardcoded-color comment.
+# List a path only when the file must contain raw colors by design (whole module is the exception).
+#
+# WordCarousel — default marketing gradient uses fixed brand hex; pass `gradient` for token-based styling.
+src/components/ui/WordCarousel/WordCarousel.tsx
+#
+# Terminal — @xterm/xterm ITheme requires hex strings for theme colors.
+src/components/Terminal/index.tsx
+#
+# Install progress bar (src/components/ui/progress-install.tsx) and similar: use CSS vars only — no entry needed.
diff --git a/src/components/Terminal/index.tsx b/src/components/Terminal/index.tsx
index 71b9702b..fed46495 100644
--- a/src/components/Terminal/index.tsx
+++ b/src/components/Terminal/index.tsx
@@ -131,9 +131,9 @@ export default function TerminalComponent({
     const terminal = new Terminal({
       theme: {
         background: 'transparent', // transparent background
-        foreground: '#ffffff', // white foreground
-        cursor: '#00ff00', // green cursor
-        cursorAccent: '#00ff00', // cursor accent
+        foreground: '#ffffff',
+        cursor: '#00ff00',
+        cursorAccent: '#00ff00',
       },
       fontFamily: '"Courier New", Courier, monospace', // monospace font
       fontSize: 12, // font size