diff --git a/AGENTS.md b/AGENTS.md
index 2fe4642..c65336c 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -70,7 +70,9 @@ Electron + electron-vite + React 终端工具（本地终端 / SSH / SFTP）。
 ## 主题机制
 
 - 终端主题由 xterm 主题派生 UI 配色：`src/renderer/src/theme/chrome.ts` 的 `applyChromeTheme` 写入 `--chrome-bg/-bg-deep/-border/-hover` CSS 变量，antd token 在 `main.tsx` ThemedConfigProvider 派生
-- 标签强调色：`settings.tabAccentColor`（默认 `#3fb950`），经 `--tab-accent` CSS 变量生效
+- **语义变量层（2026-10 主题改造）**：`src/renderer/src/theme/semantic.ts`（**零 import 纯模块**——`tests/semantic-theme.mjs` 经 Node 原生类型剥离直连它，加 import 前先想清楚）导出 `isLightTheme`/`mix`/`luminance`/`contrast`/`darkenToRatio`/`SEMANTIC` 锚点；`chrome.ts` 的 `applyChromeTheme` 随主题派生 `--ot-*` 变量并写 `color-scheme: dark|light`（原生滚动条/表单跟随）。**深色分支锁 SEMANTIC 锚点原值（零回归），浅色分支 `darkenToRatio` 按 WCAG 派生**（正文/-fg ≥4.5:1，语义基色 ≥3:1）。CSS 一律 `var(--ot-*, 锚点兜底)`，新代码禁止裸颜色字面量——`node tests/css-theme-vars.mjs` fail-closed 扫描（剥注释/color-mix/var 兜底走受控清单 FALLBACK_OK，跳过含 `${` 的模板串行，白名单按「文件+精确值」登记在测试内）；**canvas 绘制吃不到 CSS 变量**（`ctx.strokeStyle` 不解析 var()），图表类组件用 `useResolvedTheme()` + `semanticVars()` 取实色（MonitorPanel 的做法）
+- **浅色主题可读性**：内置浅色主题 ANSI 调色板已重做，16 色+fg 全部 ≥4.5:1（`node tests/theme-contrast.mjs` 守门，改浅色主题必须过它；改色用 `darkenToRatio` 统一加深算法，不许手挑色）；`minimumContrastRatio` 按「背景图 4.5｜浅色无图 4.5｜深色无图 1」矩阵（构造+热更两处都要改），`drawBoldTextInBrightColors` 浅色关闭；WebGL 渲染器同样执行 MCR（addon-webgl 自带 `_getMinimumContrastColor` 对比度路径，已核实）；antd 算法随 `isLightTheme` 切 `defaultAlgorithm`/`darkAlgorithm`（**antd 没有 lightAlgorithm，浅色就是默认算法**）；github-light 底色已柔化 `#f6f8fa`
+- 标签强调色：`settings.tabAccentColor`（默认 `#3fb950`），经 `--tab-accent` CSS 变量生效；`--tab-accent-fg` 是强调底上的文字色（明暗自适应，选中态按钮文字也用它）
 - 背景图（`settings.terminal.backgroundImage`）：图片层 `.term-bg-image` 在 xterm 画布之下（`terminal.css`），xterm 背景设 `#00000000` 透明。**图片模式下的三条铁律**：① `.terminal-view.has-bg-image .terminal-view-dock` 强制深色底衬 `#0d1117`，不能用 `--chrome-bg`——浅色主题下它是白色，调低透明度会把图洗白而不是压暗；② `minimumContrastRatio` 从 1 提到 4.5（WCAG AA，与 VS Code 终端默认值一致；TerminalView 构造与设置热更两处都要改；注意正确拼写是 `minimumContrastRatio`，`minContrastRatio` 会被静默忽略），xterm 的对比度计算把透明背景当黑色亮度，会把浅色主题的深色前景自动提亮到可读。无图时保持 1 不动主题配色。③ 压暗层（`settings.terminal.backgroundImageDim`，0–90，**默认 0**）：`.term-bg-dim` 纯黑 scrim 在 DOM 序上位于 `.term-bg-image` 之后、xterm（z-index:1）之下（同在 z-index:0 层，靠 DOM 序压图），与透明度的区别是透明度把图与深色底衬混合、压暗在图之上叠黑（保饱和但整体变暗）；**dim=0 时 TerminalView 不渲染该层，零成本**
 
 ## 终端尺寸同步
diff --git a/docs/STATE.md b/docs/STATE.md
index bbaf7ce..781d89f 100644
--- a/docs/STATE.md
+++ b/docs/STATE.md
@@ -28,6 +28,7 @@
 | M11 终端自定义（背景图/压暗层+对比度护栏）、高亮预设扩到 22 条、传输健壮性修复 | ✅（v1.0.14–1.0.16） |
 | M12 锁屏（主窗口遮罩+scrypt 密码+Ctrl+L 立即锁屏+冷却阶梯+落盘状态） | ✅（v1.0.17，v1.0.18 修复锁屏输入回归，v1.0.20 摘除菜单加固） |
 | M13 更新源改为 GitHub 优先 + Gitea 通道兜底，高亮引擎性能优化 | ✅（v1.0.19–1.0.20） |
+| M14 主题系统全面化：`--ot-*` 语义变量层、浅色主题 ANSI 调色板重做到 WCAG AA、MCR/bold/antd 算法明暗自适应、`css-theme-vars` fail-closed 守门 | ✅（2026-10-16，设计/计划见 `docs/superpowers/`；测试 22→25） |
 
 ## 锁屏实现要点（v1.0.17+，已落地）
 
diff --git a/package.json b/package.json
index 1712d29..0c9b6b5 100644
--- a/package.json
+++ b/package.json
@@ -13,7 +13,7 @@
     "preview": "electron-vite preview",
     "typecheck": "tsc --noEmit -p tsconfig.node.json && tsc --noEmit -p tsconfig.web.json",
     "pretest": "npm run typecheck",
-    "test": "node tests/build-bundles.cjs && node tests/ssh-loopback.mjs && node tests/commands-store.mjs && node tests/connections-store.mjs && node tests/settings-store.mjs && node tests/local-path-grants.mjs && node tests/lock-store.mjs && node tests/lock-controller.mjs && node tests/lock-shortcuts.mjs && node tests/reserved-accelerators.mjs && node tests/.terminal-title.cjs && node tests/ipc-guard.mjs && node tests/updater-fallback.mjs && node tests/log-sanitizer.mjs && node tests/app-log.mjs && node tests/sftp-timeout.mjs && node tests/.hl-split-smoke.cjs && node tests/.hl-rules.cjs && node tests/zmodem-e2e.mjs && node tests/ssh-session-e2e.mjs && node tests/sysinfo-e2e.mjs && node tests/terminal-cwd.mjs && node tests/terminal-links.mjs && node tests/broadcast-store.mjs && node tests/write-batcher.mjs && node tests/refit-throttle.mjs && node tests/semantic-theme.mjs && node tests/theme-contrast.mjs",
+    "test": "node tests/build-bundles.cjs && node tests/ssh-loopback.mjs && node tests/commands-store.mjs && node tests/connections-store.mjs && node tests/settings-store.mjs && node tests/local-path-grants.mjs && node tests/lock-store.mjs && node tests/lock-controller.mjs && node tests/lock-shortcuts.mjs && node tests/reserved-accelerators.mjs && node tests/.terminal-title.cjs && node tests/ipc-guard.mjs && node tests/updater-fallback.mjs && node tests/log-sanitizer.mjs && node tests/app-log.mjs && node tests/sftp-timeout.mjs && node tests/.hl-split-smoke.cjs && node tests/.hl-rules.cjs && node tests/zmodem-e2e.mjs && node tests/ssh-session-e2e.mjs && node tests/sysinfo-e2e.mjs && node tests/terminal-cwd.mjs && node tests/terminal-links.mjs && node tests/broadcast-store.mjs && node tests/write-batcher.mjs && node tests/refit-throttle.mjs && node tests/semantic-theme.mjs && node tests/theme-contrast.mjs && node tests/css-theme-vars.mjs",
     "predist": "node scripts/verify-deps.cjs && npm test && npm install --package-lock-only",
     "dist": "electron-vite build && electron-builder --win nsis",
     "dist:dir": "electron-vite build && electron-builder --win --dir"
diff --git a/tests/css-theme-vars.mjs b/tests/css-theme-vars.mjs
new file mode 100644
index 0000000..b1c096c
--- /dev/null
+++ b/tests/css-theme-vars.mjs
@@ -0,0 +1,118 @@
+/**
+ * Fail-closed guard: no raw color literals in renderer source outside the
+ * whitelist. Scans .css/.tsx/.ts under src/renderer/src. Strips comments,
+ * var() fallback bodies (those go through the controlled FALLBACK_OK list)
+ * and color-mix() bodies first; lines containing '${' are skipped wholesale
+ * (template-literal color BUILDERS like MonitorPanel's withAlpha construct
+ * rgba() from variables — they contain no literal to police).
+ * Run: node tests/css-theme-vars.mjs  (must exit 0)
+ */
+import fs from 'node:fs'
+import path from 'node:path'
+
+const ROOT = path.resolve('src/renderer/src')
+/** exact relative path -> Set of allowed lowercase literals; null = whole file exempt */
+const WHITELIST = {
+  // The layer that DEFINES the anchors and derives per-theme values.
+  'theme/semantic.ts': null,
+  // Pre-existing --chrome-* derivation anchors (mix targets / overlay bases).
+  'theme/chrome.ts': new Set([
+    '#000000', '#ffffff',
+    'rgba(0, 0, 0, 0.045)', 'rgba(0, 0, 0, 0.09)', 'rgba(0, 0, 0, 0.18)', 'rgba(0, 0, 0, 0.32)',
+    'rgba(255, 255, 255, 0.04)', 'rgba(255, 255, 255, 0.07)', 'rgba(255, 255, 255, 0.1)', 'rgba(255, 255, 255, 0.2)'
+  ]),
+  // Theme data: editor seeds itself from DEFAULT_DARK; preset swatches are rules.
+  'theme/editor/ThemeEditor.tsx': null,
+  'settings/HighlightTab.tsx': null,
+  'terminal/highlightEngine.ts': null,
+  // xterm search-match ITheme data + transparent-background markers.
+  'terminal/TerminalView.tsx': new Set(['#3b8eea', '#2d2d2d', '#c77800', '#00000000']),
+  // antd token fallbacks (mix() returning null on non-hex themes).
+  'main.tsx': new Set(['#f5f5f5', '#1f1f1f', '#252525']),
+  // :root static fallback block for --ot-*/--chrome-* (pre-JS = dark defaults).
+  'global.css': new Set([
+    '#181818', '#cccccc', '#2d2d2d', '#3b8eea', '#2a2a2a', '#101418', '#98a2ab', '#d0d0d0',
+    '#8a8a8a', '#3fb950', '#f85149', '#d29922', '#58a6ff', '#ff6b6b',
+    'rgba(255, 255, 255, 0.04)', 'rgba(255, 255, 255, 0.07)', 'rgba(255, 255, 255, 0.1)',
+    'rgba(255, 255, 255, 0.2)', 'rgba(255, 255, 255, 0.08)', 'rgba(255, 255, 255, 0.16)',
+    'rgba(204, 204, 204, 0.78)', 'rgba(204, 204, 204, 0.05)',
+    'rgba(24, 26, 31, 0.85)', 'rgba(125, 145, 170, 0.5)', 'rgba(150, 172, 200, 0.7)',
+    'rgba(0, 0, 0, 0.45)', 'rgba(59, 142, 234, 0.2)'
+  ]),
+  // Background-image iron laws: dark dock backing #0d1117, dim scrim #000,
+  // transparent xterm bg #00000000, deliberate dark dead-process scrim.
+  'terminal/terminal.css': new Set(['#0d1117', '#00000000', '#000', '#fff', 'rgba(0, 0, 0, 0.55)'])
+}
+/** values allowed inside var(x, <fallback>) — the historical literal set. */
+const FALLBACK_OK = new Set([
+  '#cccccc', '#8a8a8a', '#9a9a9a', '#6a6a6a', '#d0d0d0', '#ffffff', '#fff', '#000', '#000000',
+  '#3fb950', '#f85149', '#cf6679', '#ff6b6b', '#ff4d4f', '#d29922', '#e3b341', '#f0a55a',
+  '#f2cc60', '#4cc38a', '#6aa9ff', '#3fd06a', '#58a6ff', '#3b8eea', '#1f1f1f', '#0d1117',
+  '#f5f5f5', '#252525', '#2d2d2d', '#181818', '#101418',
+  '#e8e8e8', '#10141a', '#98a2ab', '#4ad476', '#46c96a',
+  'rgba(255, 255, 255, 0.04)', 'rgba(255, 255, 255, 0.05)', 'rgba(255, 255, 255, 0.07)',
+  'rgba(255, 255, 255, 0.08)', 'rgba(255, 255, 255, 0.1)', 'rgba(255, 255, 255, 0.16)',
+  'rgba(255, 255, 255, 0.2)', 'rgba(255, 255, 255, 0.24)', 'rgba(255, 255, 255, 0.45)',
+  'rgba(255, 255, 255, 0.55)', 'rgba(255, 255, 255, 0.85)', 'rgba(255, 255, 255, 0.88)',
+  'rgba(0, 0, 0, 0.06)', 'rgba(0, 0, 0, 0.14)', 'rgba(0, 0, 0, 0.22)',
+  'rgba(0, 0, 0, 0.28)', 'rgba(0, 0, 0, 0.4)', 'rgba(0, 0, 0, 0.45)', 'rgba(0, 0, 0, 0.55)',
+  'rgba(24, 26, 31, 0.85)', 'rgba(125, 145, 170, 0.5)', 'rgba(150, 172, 200, 0.7)',
+  'rgba(59, 142, 234, 0.18)', 'rgba(59, 142, 234, 0.2)', 'rgba(59, 142, 234, 0.75)',
+  'rgba(148, 163, 184, 0.28)', 'rgba(121, 121, 121, 0.45)', 'rgba(90, 93, 94, 0.31)'
+])
+
+function walk(dir, out = []) {
+  for (const f of fs.readdirSync(dir)) {
+    const p = path.join(dir, f)
+    if (fs.statSync(p).isDirectory()) walk(p, out)
+    else if (/\.(css|tsx|ts)$/.test(f)) out.push(p)
+  }
+  return out
+}
+const stripComments = (s) => s.replace(/\/\*[\s\S]*?\*\//g, '').replace(/(^|[^:'"])\/\/.*$/gm, '$1')
+const COLOR = /#[0-9a-fA-F]{3,8}\b(?![-\w])|rgba?\([^)]*\)/g
+
+let violations = 0
+for (const file of walk(ROOT)) {
+  const rel = path.relative(ROOT, file).split(path.sep).join('/')
+  const wl = WHITELIST[rel]
+  if (wl === null) continue
+  const raw = stripComments(fs.readFileSync(file, 'utf8'))
+  const outsideVar = raw.replace(/var\([^)]*\)/g, '()').replace(/color-mix\([^)]*\)/g, '()')
+  const lines = outsideVar.split(/\r?\n/)
+  lines.forEach((line, idx) => {
+    if (line.includes('${')) return // template-literal color builder, not a literal
+    for (const m of line.matchAll(COLOR)) {
+      const lit = m[0].toLowerCase()
+      if (wl && wl.has(lit)) continue
+      console.error(`RAW ${rel}:${idx + 1}: ${lit}`)
+      violations++
+    }
+  })
+  for (const v of raw.matchAll(/var\(([^)]*)\)/g)) {
+    let fb = v[1].split(',').slice(1).join(',').trim()
+    if (!fb || fb.startsWith('var(')) continue
+    // var(a, rgba(...)) — the [^)]* capture stops at rgba's ')'; restore it
+    if (fb.startsWith('rgb') && !fb.endsWith(')')) fb += ')'
+    for (const lit of fb.match(COLOR) ?? []) {
+      if (!FALLBACK_OK.has(lit.toLowerCase())) {
+        console.error(`FALLBACK ${rel}: var(${v[1]}) -> ${lit}`)
+        violations++
+      }
+    }
+  }
+}
+// negative self-test: the matcher must catch literals incl. 3/4-digit hex
+{
+  const probe = stripComments('.a{color:#fff9;border:#abcd}')
+  const hits = [...probe.matchAll(COLOR)].length
+  if (hits < 2) {
+    console.error('self-test failed: matcher did not catch probe literals')
+    process.exit(1)
+  }
+}
+if (violations > 0) {
+  console.error(`css-theme-vars: ${violations} violation(s)`)
+  process.exit(1)
+}
+console.log('css-theme-vars: all ok')