diff --git a/packages/client/src/components/hermes/settings/DisplaySettings.vue b/packages/client/src/components/hermes/settings/DisplaySettings.vue
index cda6968..0bcb479 100644
--- a/packages/client/src/components/hermes/settings/DisplaySettings.vue
+++ b/packages/client/src/components/hermes/settings/DisplaySettings.vue
@@ -3,7 +3,6 @@ import { computed } from 'vue'
 import { useMessage } from '@/composables/useMessage'
 import { useI18n } from 'vue-i18n'
 import { useSettingsStore } from '@/stores/hermes/settings'
-import { useTheme, type BrightnessMode } from '@/composables/useTheme'
 import { requestCompletionNotificationPermission, showCompletionNotification, type CompletionNotificationPermissionResult } from '@/utils/completion-notification'
 import { clampChatInputHeight, MAX_CHAT_INPUT_HEIGHT, MIN_CHAT_INPUT_HEIGHT } from '@/utils/chat-input-height'
 import SettingRow from './SettingRow.vue'
@@ -11,13 +10,7 @@ import SettingRow from './SettingRow.vue'
 const settingsStore = useSettingsStore()
 const message = useMessage()
 const { t } = useI18n()
-const { brightness, setBrightness } = useTheme()
 
-const themeOptions = [
-  { label: t('settings.display.themeLight'), value: 'light' },
-  { label: t('settings.display.themeDark'), value: 'dark' },
-  { label: t('settings.display.themeSystem'), value: 'system' },
-]
 const chatInputHeight = computed(() => clampChatInputHeight(settingsStore.display.chat_input_height))
 
 async function save(values: Record<string, any>) {
@@ -29,12 +22,6 @@ async function save(values: Record<string, any>) {
   }
 }
 
-function handleThemeChange(val: string) {
-  const m = val as BrightnessMode
-  setBrightness(m)
-  save({ skin: m })
-}
-
 function handleChatInputHeightChange(value: number | null) {
   return save({ chat_input_height: clampChatInputHeight(value) })
 }
@@ -90,9 +77,6 @@ async function testCompletionNotification() {
 
 <template>
   <section class="settings-section">
-    <SettingRow :label="t('settings.display.theme')" :hint="t('settings.display.themeHint')">
-      <a-select :model-value="brightness" :options="themeOptions" size="small" class="input-sm" @update:model-value="v => handleThemeChange(String(v))" />
-    </SettingRow>
     <SettingRow :label="t('settings.display.streaming')" :hint="t('settings.display.streamingHint')">
       <a-switch :model-value="settingsStore.display.streaming" @update:model-value="v => save({ streaming: v })" />
     </SettingRow>
diff --git a/packages/client/src/components/layout/AppSidebar.vue b/packages/client/src/components/layout/AppSidebar.vue
index 5d326e2..dec85b4 100644
--- a/packages/client/src/components/layout/AppSidebar.vue
+++ b/packages/client/src/components/layout/AppSidebar.vue
@@ -9,7 +9,6 @@ import RouteLinkItem from '@/components/common/RouteLinkItem.vue'
 import ModelSelector from "@/components/layout/ModelSelector.vue";
 import ProfileSelector from "@/components/layout/ProfileSelector.vue";
 import LanguageSwitch from "@/components/layout/LanguageSwitch.vue";
-import ThemeSwitch from "@/components/layout/ThemeSwitch.vue";
 import { changelog } from "@/data/changelog";
 import { getStoredUsername, isStoredSuperAdmin } from "@/api/client";
 
@@ -350,7 +349,6 @@ function handleUpdateClick() {
         >
           Studio v{{ appStore.serverVersion || "0.1.0" }}
         </span>
-        <ThemeSwitch />
       </div>
       <a-button v-if="appStore.clientOutdated" type="primary" status="warning" size="mini" long class="update-btn" @click="handleReloadClient">
         {{ t('sidebar.reloadClientVersion', { version: appStore.serverVersion }) }}
@@ -662,10 +660,6 @@ function handleUpdateClick() {
   }
 }
 
-.version-info :deep(.theme-switch-container) {
-  flex-shrink: 0;
-}
-
 .update-btn {
   margin: 4px 0 0;
   border-radius: $radius-sm;
diff --git a/packages/client/src/components/layout/ThemeSwitch.vue b/packages/client/src/components/layout/ThemeSwitch.vue
deleted file mode 100644
index 4eb6793..0000000
--- a/packages/client/src/components/layout/ThemeSwitch.vue
+++ /dev/null
@@ -1,59 +0,0 @@
-<script setup lang="ts">
-import { useTheme } from '@/composables/useTheme'
-
-const { isDark, isComic, toggleBrightness, toggleStyle } = useTheme()
-</script>
-
-<template>
-  <div class="theme-switch-container" style="display: flex; gap: 4px; align-items: center;">
-    <button class="theme-switch" :title="isComic ? 'Ink style' : 'Comic style'" @click="toggleStyle">
-      <!-- Palette icon for comic toggle -->
-      <svg v-if="isComic" width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
-        <path d="M12 2.69l5.66 5.66a8 8 0 1 1-11.31 0z" />
-      </svg>
-      <!-- Sparkle icon for ink mode -->
-      <svg v-else width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
-        <path d="M12 3l1.5 5.5L19 10l-5.5 1.5L12 17l-1.5-5.5L5 10l5.5-1.5L12 3z" />
-      </svg>
-    </button>
-    <button class="theme-switch" :title="isDark ? 'Light mode' : 'Dark mode'" @click="toggleBrightness">
-      <!-- Sun icon (shown in dark mode) -->
-      <svg v-if="isDark" width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
-        <circle cx="12" cy="12" r="5" />
-        <line x1="12" y1="1" x2="12" y2="3" />
-        <line x1="12" y1="21" x2="12" y2="23" />
-        <line x1="4.22" y1="4.22" x2="5.64" y2="5.64" />
-        <line x1="18.36" y1="18.36" x2="19.78" y2="19.78" />
-        <line x1="1" y1="12" x2="3" y2="12" />
-        <line x1="21" y1="12" x2="23" y2="12" />
-        <line x1="4.22" y1="19.78" x2="5.64" y2="18.36" />
-        <line x1="18.36" y1="5.64" x2="19.78" y2="4.22" />
-      </svg>
-      <!-- Moon icon (shown in light mode) -->
-      <svg v-else width="16" height="16" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
-        <path d="M21 12.79A9 9 0 1 1 11.21 3 7 7 0 0 0 21 12.79z" />
-      </svg>
-    </button>
-  </div>
-</template>
-
-<style scoped lang="scss">
-.theme-switch {
-  display: flex;
-  align-items: center;
-  justify-content: center;
-  width: 28px;
-  height: 28px;
-  border: none;
-  background: transparent;
-  border-radius: 4px;
-  cursor: pointer;
-  color: var(--text-muted);
-  transition: color 0.15s ease, background-color 0.15s ease;
-
-  &:hover {
-    color: var(--text-primary);
-    background: rgba(var(--accent-primary-rgb), 0.06);
-  }
-}
-</style>
diff --git a/packages/client/src/composables/useTheme.ts b/packages/client/src/composables/useTheme.ts
index 6d1f210..9534225 100644
--- a/packages/client/src/composables/useTheme.ts
+++ b/packages/client/src/composables/useTheme.ts
@@ -1,91 +1,28 @@
-import { ref, watch, computed } from 'vue'
+import { ref, computed } from 'vue'
 
-export type BrightnessMode = 'light' | 'dark' | 'system'
-export type ThemeStyle = 'ink' | 'comic'
+// CYBER 是单色暗色主题：亮度与风格切换器已移除（comic 与 light 主题不再提供）。
+// 这里保留 isDark 以兼容 App.vue / JourneyView 里的 :class 绑定，值恒为 true。
+const isDark = ref(true)
 
-const BRIGHTNESS_KEY = 'hermes_brightness'
-const STYLE_KEY = 'hermes_style'
+export type BrightnessMode = 'dark'
 
-const brightness = ref<BrightnessMode>(
-  (localStorage.getItem(BRIGHTNESS_KEY) as BrightnessMode) || 'system',
-)
+const brightness = ref<BrightnessMode>('dark')
 
-const style = ref<ThemeStyle>(
-  (localStorage.getItem(STYLE_KEY) as ThemeStyle) || 'ink',
-)
-
-const isDark = ref(false)
-const isComic = ref(false)
-
-function resolveDark(b: BrightnessMode): boolean {
-  if (b === 'system') {
-    return window.matchMedia('(prefers-color-scheme: dark)').matches
-  }
-  return b === 'dark'
-}
-
-function applyClasses() {
-  const dark = resolveDark(brightness.value)
-  isDark.value = dark
-  isComic.value = style.value === 'comic'
-  document.documentElement.classList.toggle('dark', dark)
-  document.documentElement.classList.toggle('comic', isComic.value)
-  // Arco Design dark theme mechanism (Phase 005)
-  document.documentElement.setAttribute('arco-theme', dark ? 'dark' : 'light')
-}
-
-// Initial
-applyClasses()
-
-// Listen for system preference changes
-window.matchMedia('(prefers-color-scheme: dark)').addEventListener('change', () => {
-  if (brightness.value === 'system') {
-    applyClasses()
-  }
-})
-
-// Persist & apply on change
-watch(brightness, (b) => {
-  localStorage.setItem(BRIGHTNESS_KEY, b)
-  applyClasses()
-})
-
-watch(style, (s) => {
-  localStorage.setItem(STYLE_KEY, s)
-  applyClasses()
-})
+// 固定应用暗色：Arco 的 token 通过 arco-theme 属性切换，项目的令牌写在 :root。
+document.documentElement.setAttribute('arco-theme', 'dark')
 
 export function useTheme() {
-  const themeName = computed(() => {
-    const b = isDark.value ? 'dark' : 'light'
-    return isComic.value ? `comic-${b}` : b
-  })
+  const themeName = computed(() => 'dark')
 
-  function setBrightness(b: BrightnessMode) {
-    brightness.value = b
-  }
-
-  function setStyle(s: ThemeStyle) {
-    style.value = s
-  }
-
-  function toggleBrightness() {
-    brightness.value = isDark.value ? 'light' : 'dark'
-  }
-
-  function toggleStyle() {
-    style.value = isComic.value ? 'ink' : 'comic'
+  function setBrightness(_b: BrightnessMode) {
+    // 单主题：忽略任何切换请求。
+    brightness.value = 'dark'
   }
 
   return {
     brightness,
-    style,
     isDark,
-    isComic,
     themeName,
     setBrightness,
-    setStyle,
-    toggleBrightness,
-    toggleStyle,
   }
 }
diff --git a/packages/client/src/i18n/locales/en.ts b/packages/client/src/i18n/locales/en.ts
index e50269e..b0524b7 100644
--- a/packages/client/src/i18n/locales/en.ts
+++ b/packages/client/src/i18n/locales/en.ts
@@ -1575,11 +1575,6 @@ export default {
       notifyOnCompleteTestFailed: 'Failed to send test notification',
       busyInputMode: 'Busy Input Mode',
       busyInputModeHint: 'Allow input while AI is processing',
-      theme: 'Theme',
-      themeHint: 'Choose light, dark, or follow system preference',
-      themeLight: 'Light',
-      themeDark: 'Dark',
-      themeSystem: 'System',
       chatInputHeight: 'Chat input height',
       chatInputHeightHint: 'Default chat input height in pixels on wide screens. Mobile keeps auto height.'
     },
diff --git a/packages/client/src/i18n/locales/zh.ts b/packages/client/src/i18n/locales/zh.ts
index 39c174d..266360c 100644
--- a/packages/client/src/i18n/locales/zh.ts
+++ b/packages/client/src/i18n/locales/zh.ts
@@ -1567,11 +1567,6 @@ export default {
       notifyOnCompleteTestFailed: '测试通知发送失败',
       busyInputMode: '忙碌输入模式',
       busyInputModeHint: 'AI 处理中仍可输入',
-      theme: '主题',
-      themeHint: '选择浅色、暗色或跟随系统',
-      themeLight: '浅色',
-      themeDark: '暗色',
-      themeSystem: '跟随系统',
       chatInputHeight: '聊天输入框高度',
       chatInputHeightHint: '桌面端聊天输入框默认高度（像素）。移动端保持自动高度。'
     },
diff --git a/packages/client/src/main.ts b/packages/client/src/main.ts
index 0aefd53..fc10cae 100644
--- a/packages/client/src/main.ts
+++ b/packages/client/src/main.ts
@@ -8,24 +8,8 @@ import App from './App.vue'
 import './styles/global.scss'
 import 'katex/dist/katex.min.css'
 
-// Apply theme classes before mount to prevent FOUC (Flash of Unstyled Content)
-const savedBrightness = localStorage.getItem('hermes_brightness') || 'system'
-const savedStyle = localStorage.getItem('hermes_style') || 'ink'
-
-// Resolve dark mode
-const prefersDark = window.matchMedia('(prefers-color-scheme: dark)').matches
-const isDark = savedBrightness === 'dark' || (savedBrightness === 'system' && prefersDark)
-
-// Resolve style
-const isComic = savedStyle === 'comic'
-
-// Apply classes to prevent FOUC
-if (isDark) {
-  document.documentElement.classList.add('dark')
-}
-if (isComic) {
-  document.documentElement.classList.add('comic')
-}
+// CYBER 单主题：固定暗色，无需读取 localStorage 或匹配系统偏好。
+document.documentElement.setAttribute('arco-theme', 'dark')
 
 // Read token from URL BEFORE router initializes (hash router strips params)
 const urlParams = new URLSearchParams(window.location.search)
diff --git a/packages/client/src/styles/arco-theme.ts b/packages/client/src/styles/arco-theme.ts
index c7c58b3..36fa901 100644
--- a/packages/client/src/styles/arco-theme.ts
+++ b/packages/client/src/styles/arco-theme.ts
@@ -1,14 +1,20 @@
-// Arco Design theme tokens for hermes-ui (Phase 005 baseline).
-// Dark mode is carried by `body[arco-theme='dark']` CSS overrides, not a second theme object.
-// See docs/ui-baseline.md for the frozen visual language.
+// Arco Design theme tokens for hermes-ui — CYBER.
+//
+// 这些值是「参考值」，不是运行时来源：项目没有挂 ConfigProvider，Arco 的实际外观
+// 由 styles/global.scss 里的 --color-* 变量覆盖决定（见那里的 Arco token bridge）。
+// 保留本文件是为了让读取 token 的人能在一处看到意图，以及给测试一个可断言的锚点。
+// 改色时请同时改 global.scss 的 Arco token bridge，两处保持一致。
 export const arcoTheme = {
-  // 延续旧版克制灰阶
-  colorPrimary: '#2f2f2f',
-  colorBgLayout: '#fafafa',
-  colorBgContainer: '#ffffff',
+  // 霓虹青 oklch(0.805 0.148 188) ≈ rgb(45, 212, 191)
+  colorPrimary: '#2dd4bf',
+  // 页面底 / 卡片底，对应 oklch(0.155 0.012 250) 与 oklch(0.130 0.012 250)
+  colorBgLayout: '#1a1d23',
+  colorBgContainer: '#14171c',
   borderRadius: 6,
-  fontFamily: 'Inter, system-ui, -apple-system, sans-serif',
-  fontFamilyMono: '"JetBrains Mono", "Fira Code", monospace',
+  fontFamily:
+    '-apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", Roboto, sans-serif',
+  fontFamilyMono:
+    'ui-monospace, "JetBrains Mono", "SF Mono", Menlo, "Cascadia Code", monospace',
 }
 
 export type ArcoTheme = typeof arcoTheme
diff --git a/packages/client/src/styles/global.scss b/packages/client/src/styles/global.scss
index e4ff928..42db6fa 100644
--- a/packages/client/src/styles/global.scss
+++ b/packages/client/src/styles/global.scss
@@ -1,54 +1,6 @@
 @use 'variables' as *;
 @use 'code-block';
 
-@font-face {
-  font-family: 'Comic Neue';
-  font-style: normal;
-  font-weight: 400;
-  font-display: swap;
-  src: url('/fonts/ComicNeue-Bold.ttf') format('truetype');
-}
-
-@font-face {
-  font-family: 'ZCOOL KuaiLe';
-  font-style: normal;
-  font-weight: 400;
-  font-display: swap;
-  src: url('/fonts/ZCOOLKuaiLe-Regular.ttf') format('truetype');
-}
-
-@font-face {
-  font-family: 'Zen Maru Gothic';
-  font-style: normal;
-  font-weight: 400;
-  font-display: swap;
-  src: url('/fonts/ZenMaruGothic-Regular.ttf') format('truetype');
-}
-
-@font-face {
-  font-family: 'Zen Maru Gothic';
-  font-style: normal;
-  font-weight: 700;
-  font-display: swap;
-  src: url('/fonts/ZenMaruGothic-Bold.ttf') format('truetype');
-}
-
-@font-face {
-  font-family: 'Gaegu';
-  font-style: normal;
-  font-weight: 400;
-  font-display: swap;
-  src: url('/fonts/Gaegu-Regular.ttf') format('truetype');
-}
-
-@font-face {
-  font-family: 'Gaegu';
-  font-style: normal;
-  font-weight: 700;
-  font-display: swap;
-  src: url('/fonts/Gaegu-Bold.ttf') format('truetype');
-}
-
 *,
 *::before,
 *::after {
@@ -75,13 +27,98 @@ textarea {
   }
 }
 
-// Theme transition (applied programmatically on toggle, not on load)
-html.theme-transitioning,
-html.theme-transitioning *,
-html.theme-transitioning *::before,
-html.theme-transitioning *::after {
-  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease,
-              box-shadow 0.3s ease, fill 0.3s ease, stroke 0.3s ease !important;
+// ─── Arco Design token bridge ──────────────────────────────────
+// arco-theme.ts 不是运行时来源（没有 ConfigProvider），Arco 的实际外观由 arco.css
+// 里的 --color-* 变量决定。这里把 CYBER 令牌翻译成 Arco 变量，让 a-select /
+// a-input / a-tag / a-table / a-modal 等自有控件与项目配色对齐。
+// 变量表见 node_modules/@arco-design/web-vue/dist/arco.css 的 :root 块。
+html[arco-theme='dark'],
+:root {
+  --color-primary-light-1: oklch(0.30 0.060 188);
+  --color-primary-light-2: oklch(0.39 0.075 188);
+  --color-primary-light-3: oklch(0.50 0.095 188);
+  --color-primary-light-4: oklch(0.60 0.115 188);
+  --color-primary-light-5: oklch(0.68 0.130 188);
+  --color-primary-light-6: oklch(0.805 0.148 188);
+  --color-primary: oklch(0.805 0.148 188);
+  --color-primary-dark-1: oklch(0.760 0.144 188);
+  --color-primary-dark-2: oklch(0.700 0.138 188);
+  --color-primary-dark-3: oklch(0.640 0.130 188);
+  --color-primary-dark-4: oklch(0.580 0.120 188);
+  --color-primary-dark-5: oklch(0.520 0.108 188);
+  --color-primary-dark-6: oklch(0.460 0.094 188);
+
+  --color-success-light-1: oklch(0.28 0.050 165);
+  --color-success-light-2: oklch(0.42 0.078 165);
+  --color-success-light-3: oklch(0.58 0.108 165);
+  --color-success: oklch(0.760 0.140 165);
+
+  --color-warning-light-1: oklch(0.30 0.052 85);
+  --color-warning-light-2: oklch(0.46 0.082 85);
+  --color-warning-light-3: oklch(0.62 0.112 85);
+  --color-warning: oklch(0.810 0.145 85);
+
+  --color-danger-light-1: oklch(0.28 0.062 22);
+  --color-danger-light-2: oklch(0.42 0.096 22);
+  --color-danger-light-3: oklch(0.56 0.138 22);
+  --color-danger: oklch(0.665 0.185 22);
+
+  --color-link-light-1: oklch(0.30 0.060 188);
+  --color-link-light-2: oklch(0.42 0.084 188);
+  --color-link-light-3: oklch(0.54 0.110 188);
+  --color-link-light-4: oklch(0.66 0.136 188);
+  --color-link-light-5: oklch(0.74 0.148 188);
+  --color-link-light-6: oklch(0.805 0.148 188);
+  --color-link: oklch(0.805 0.148 188);
+
+  // 容器与文字
+  --color-text-1: oklch(0.945 0.006 200);
+  --color-text-2: oklch(0.860 0.008 210);
+  --color-text-3: oklch(0.705 0.014 230);
+  --color-text-4: oklch(0.520 0.014 236);
+  --color-text-disabled: oklch(0.420 0.012 238);
+
+  --color-bg-1: oklch(0.155 0.012 250);
+  --color-bg-2: oklch(0.130 0.012 250);
+  --color-bg-3: oklch(0.185 0.014 248);
+  --color-bg-4: oklch(0.225 0.016 246);
+  --color-bg-5: oklch(0.255 0.018 247);
+  --color-fill-1: oklch(0.185 0.014 248);
+  --color-fill-2: oklch(0.225 0.016 246);
+  --color-fill-3: oklch(0.255 0.018 247);
+  --color-fill-4: oklch(0.285 0.018 246);
+
+  --color-border-1: oklch(0.305 0.018 242);
+  --color-border-2: oklch(0.255 0.016 244);
+  --color-border-3: oklch(0.225 0.014 246);
+  --color-border-4: oklch(0.195 0.014 248);
+
+  --color-fill-2-hover: oklch(0.255 0.018 247);
+  --color-fill-3-hover: oklch(0.285 0.018 246);
+
+  --radius-small: 4px;
+  --radius-medium: 6px;
+  --radius-large: 8px;
+
+  --font-size-body-1: 14px;
+  --font-size-body-2: 13px;
+  --font-size-body-3: 12px;
+
+  // CYBER 的核心排版特征：标题、页头、数据用等宽
+  --font-family: #{$font-ui};
+  --font-family-body: #{$font-ui};
+  --font-family-code: #{$font-code};
+}
+
+// Arco 暗色态：强制走暗色变量（属性挂在 <html> 上，Arco 官方选择器可能匹配 body）
+body {
+  color: $text-primary;
+  background-color: $bg-primary;
+}
+
+// Arco 组件里的滚动条与焦点环对齐 CYBER
+.arco-scrollbar-thumb {
+  background-color: $border-color !important;
 }
 
 html, body {
@@ -146,8 +183,8 @@ a {
 }
 
 ::-webkit-scrollbar {
-  width: 6px;
-  height: 6px;
+  width: 8px;
+  height: 8px;
   background: transparent;
 }
 
@@ -158,10 +195,10 @@ a {
 
 ::-webkit-scrollbar-thumb {
   background: $border-color;
-  border-radius: 3px;
+  border-radius: 4px;
 
   &:hover {
-    background: $text-muted;
+    background: rgba(var(--accent-primary-rgb), 0.5);
   }
 }
 
diff --git a/packages/client/src/styles/variables.scss b/packages/client/src/styles/variables.scss
index 0dd7cb8..e8a9899 100644
--- a/packages/client/src/styles/variables.scss
+++ b/packages/client/src/styles/variables.scss
@@ -1,132 +1,64 @@
-// 黑白水墨 — Pure Ink
-// 纯黑白灰，无彩色
-// 支持 light / dark / comic 三主题
+// CYBER — 霓虹暗色单主题
+// 设计语言见 prototype_reference/hermes-ui-cyber-api.html 与 hermes-ui-cyber-login.html。
+// 暗色为唯一主题：亮度/风格切换器已移除，因此这里只有一组令牌，没有 .dark / .comic 变体。
+// 唯一强调色是霓虹青 oklch(0.805 0.148 188)，状态色仅用于语义，不参与装饰。
 
 // ─── CSS Custom Properties ─────────────────────────────────────
 
 :root {
-  // Backgrounds
-  --bg-primary: #fafafa;
-  --bg-secondary: #f0f0f0;
-  --bg-sidebar: #f5f5f5;
-  --bg-card: #ffffff;
-  --bg-card-hover: #fafafa;
-  --bg-input: #ffffff;
+  // Backgrounds — 由深到浅的四层
+  --bg-primary: oklch(0.155 0.012 250);   // 页面底色
+  --bg-secondary: oklch(0.130 0.012 250); // 卡片 / 面板（比页面更沉，向下压）
+  --bg-sidebar: oklch(0.118 0.013 251);  // 侧栏，比卡片更沉
+  --bg-card: oklch(0.185 0.014 248);     // 容器 / 输入区（比页面更亮，向上浮）
+  --bg-card-hover: oklch(0.225 0.016 246);
+  --bg-input: oklch(0.105 0.012 252);    // 输入框，比卡片更沉，形成凹陷感
 
-  // Borders
-  --border-color: #e0e0e0;
-  --border-light: #ebebeb;
+  // Borders — 发丝线分两档
+  --border-color: oklch(0.305 0.018 242);
+  --border-light: oklch(0.255 0.016 244);
 
-  // Accent
-  --accent-primary: #333333;
-  --accent-hover: #1a1a1a;
-  --accent-muted: #888888;
+  // Accent — 霓虹青，全站唯一强调色
+  --accent-primary: oklch(0.805 0.148 188);
+  --accent-hover: oklch(0.870 0.150 188);
+  --accent-muted: oklch(0.520 0.060 188);
+  --accent-soft: oklch(0.805 0.148 188 / 0.13);
+  --accent-ink: oklch(0.160 0.030 200);   // 强调色上的文字/图标（深色，保证对比）
 
   // Text
-  --text-primary: #1a1a1a;
-  --text-secondary: #666666;
-  --text-muted: #999999;
+  --text-primary: oklch(0.945 0.006 200);
+  --text-secondary: oklch(0.860 0.008 210);
+  --text-muted: oklch(0.705 0.014 230);
+  --text-faint: oklch(0.520 0.014 236);   // 禁用态 / 极次要信息
 
-  // Status
-  --success: #2e7d32;
-  --error: #c62828;
-  --warning: #f57f17;
+  // Status — 语义色，不用于装饰
+  --success: oklch(0.760 0.140 165);
+  --error: oklch(0.665 0.185 22);
+  --warning: oklch(0.810 0.145 85);
+  --accent-info: oklch(0.700 0.110 245);
 
   // Message bubbles
-  --msg-user-bg: #f5f5f5;
-  --msg-assistant-bg: #f5f5f5;
-  --msg-system-border: #bdbdbd;
+  --msg-user-bg: oklch(0.225 0.016 246);
+  --msg-assistant-bg: oklch(0.185 0.014 248);
+  --msg-system-border: oklch(0.305 0.018 242);
 
   // Code
-  --code-bg: #f4f4f4;
+  --code-bg: oklch(0.115 0.014 250);
 
   // Utility
-  --text-on-accent: #ffffff;
-  --text-on-overlay: #ffffff;
-  --accent-info: #4a90d9;
+  --text-on-accent: oklch(0.160 0.030 200);
+  --text-on-overlay: oklch(0.945 0.006 200);
 
   // RGB components (for rgba() usage)
-  --accent-primary-rgb: 51, 51, 51;
-  --accent-hover-rgb: 26, 26, 26;
-  --text-primary-rgb: 26, 26, 26;
-  --text-muted-rgb: 153, 153, 153;
-  --success-rgb: 46, 125, 50;
-  --error-rgb: 198, 40, 40;
-  --warning-rgb: 245, 127, 23;
-  --accent-info-rgb: 74, 144, 217;
-}
-
-.dark {
-  // Backgrounds
-  --bg-primary: #1a1a1a;
-  --bg-secondary: #252525;
-  --bg-sidebar: #202020;
-  --bg-card: #2a2a2a;
-  --bg-card-hover: #333333;
-  --bg-input: #2a2a2a;
-
-  // Borders
-  --border-color: #3a3a3a;
-  --border-light: #333333;
-
-  // Accent
-  --accent-primary: #e0e0e0;
-  --accent-hover: #f5f5f5;
-  --accent-muted: #888888;
-
-  // Text
-  --text-primary: #e0e0e0;
-  --text-secondary: #a0a0a0;
-  --text-muted: #888888;
-
-  // Status
-  --success: #66bb6a;
-  --error: #ef5350;
-  --warning: #ffb74d;
-
-  // Message bubbles
-  --msg-user-bg: #252525;
-  --msg-assistant-bg: #252525;
-  --msg-system-border: #555555;
-
-  // Code
-  --code-bg: #1e1e1e;
-
-  // Utility
-  --text-on-accent: #1a1a1a;
-  --text-on-overlay: #ffffff;
-  --accent-info: #6ba3d6;
-
-  // RGB components
-  --accent-primary-rgb: 224, 224, 224;
-  --accent-hover-rgb: 245, 245, 245;
-  --text-primary-rgb: 224, 224, 224;
-  --text-muted-rgb: 136, 136, 136;
-  --success-rgb: 102, 187, 106;
-  --error-rgb: 239, 83, 80;
-  --warning-rgb: 255, 183, 77;
-  --accent-info-rgb: 107, 163, 214;
-}
-
-.comic {
-  // Borders — bold comic outlines
-  --border-color: #1a1a1a;
-  --border-light: #555555;
-  --msg-system-border: #1a1a1a;
-
-  // Comic-specific
-  --font-ui: 'Comic Neue', 'ZCOOL KuaiLe', 'Zen Maru Gothic', 'Gaegu', cursive, sans-serif;
-  --comic-border-width: 2.5px;
-  --comic-shadow: 3px 3px 0px rgba(0, 0, 0, 0.15);
-}
-
-.dark.comic {
-  // Borders — brighter outlines on dark
-  --border-color: #666666;
-  --border-light: #555555;
-  --msg-system-border: #888888;
-
-  --comic-shadow: 3px 3px 0px rgba(255, 255, 255, 0.08);
+  // 霓虹青 oklch(0.805 0.148 188) ≈ rgb(45, 212, 191)
+  --accent-primary-rgb: 45, 212, 191;
+  --accent-hover-rgb: 74, 226, 205;
+  --text-primary-rgb: 240, 246, 247;
+  --text-muted-rgb: 168, 180, 187;
+  --success-rgb: 47, 197, 138;
+  --error-rgb: 232, 78, 61;
+  --warning-rgb: 226, 175, 32;
+  --accent-info-rgb: 105, 160, 232;
 }
 
 // ─── SCSS Variables (delegate to CSS custom properties) ────────
@@ -157,7 +89,7 @@ $text-muted: var(--text-muted);
 $success: var(--success);
 $error: var(--error);
 $warning: var(--warning);
-$info: $accent-primary;
+$info: var(--accent-info);
 
 // Message bubbles
 $msg-user-bg: var(--msg-user-bg);
@@ -168,16 +100,19 @@ $msg-system-border: var(--msg-system-border);
 $code-bg: var(--code-bg);
 
 // Typography
-$font-ui: var(--font-ui, 'Inter', system-ui, -apple-system, sans-serif);
-$font-code: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;
+// 正文用系统无衬线，标识/数据/代码用等宽——这是 CYBER 的核心排版特征。
+$font-ui: -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Hiragino Sans GB',
+  'Microsoft YaHei', 'Segoe UI', Roboto, sans-serif;
+$font-code: ui-monospace, 'JetBrains Mono', 'SF Mono', Menlo, 'Cascadia Code', monospace;
+$font-display: $font-code;
 
-// Layout
+// Layout — 与 docs/ui-baseline.md 保持一致
 $sidebar-width: 240px;
 $sidebar-collapsed-width: 64px;
 $header-height: 60px;
 $breakpoint-mobile: 768px;
 
-// Radius
+// Radius — 发丝线 + 小圆角，硬边而非圆润
 $radius-sm: 6px;
 $radius-md: 8px;
 $radius-lg: 8px;
diff --git a/tests/client/sidebar-search.test.ts b/tests/client/sidebar-search.test.ts
index d498521..97e9325 100644
--- a/tests/client/sidebar-search.test.ts
+++ b/tests/client/sidebar-search.test.ts
@@ -68,10 +68,6 @@ vi.mock('@/components/layout/LanguageSwitch.vue', () => ({
   default: { name: 'LanguageSwitch', template: '<div />' },
 }))
 
-vi.mock('@/components/layout/ThemeSwitch.vue', () => ({
-  default: { name: 'ThemeSwitch', template: '<div />' },
-}))
-
 vi.mock('@/components/common/RouteLinkItem.vue', () => ({
   default: {
     name: 'RouteLinkItem',
@@ -135,7 +131,6 @@ describe('AppSidebar navigation', () => {
           ProfileSelector: true,
           ModelSelector: true,
           LanguageSwitch: true,
-          ThemeSwitch: true,
         },
       },
     })
@@ -153,7 +148,6 @@ describe('AppSidebar navigation', () => {
           ProfileSelector: true,
           ModelSelector: true,
           LanguageSwitch: true,
-          ThemeSwitch: true,
         },
       },
     })
@@ -181,7 +175,6 @@ describe('AppSidebar navigation', () => {
           ProfileSelector: true,
           ModelSelector: true,
           LanguageSwitch: true,
-          ThemeSwitch: true,
         },
       },
     })
@@ -200,7 +193,6 @@ describe('AppSidebar navigation', () => {
           ProfileSelector: true,
           ModelSelector: true,
           LanguageSwitch: true,
-          ThemeSwitch: true,
         },
       },
     })
@@ -225,7 +217,6 @@ describe('AppSidebar navigation', () => {
           ProfileSelector: true,
           ModelSelector: true,
           LanguageSwitch: true,
-          ThemeSwitch: true,
         },
       },
     })
diff --git a/tests/client/style-system.test.ts b/tests/client/style-system.test.ts
index 59d63a8..89703ce 100644
--- a/tests/client/style-system.test.ts
+++ b/tests/client/style-system.test.ts
@@ -15,12 +15,24 @@ describe('client style system', () => {
   it('aligns SCSS surfaces and radii with the shared theme tokens', () => {
     const variables = readClientFile('styles/variables.scss')
 
-    expect(variables).toContain('--bg-card: #ffffff;')
-    // 深色主题必须重新定义 card surface，否则浅色值会漏到深色模式
-    expect(variables).toContain('--bg-card: #2a2a2a;')
+    // CYBER 是单色暗色主题：卡片面必须是暗色，且亮度分层（page < sidebar < card < input）。
+    expect(variables).toContain('--bg-card: oklch(0.185 0.014 248);')
+    expect(variables).toContain('--bg-input: oklch(0.105 0.012 252);')
     expect(variables).toContain('$radius-sm: 6px;')
     expect(variables).toContain('$radius-md: 8px;')
     expect(variables).toContain('$radius-lg: 8px;')
+    // 亮色主题与 comic 风格已移除：不能再有 .dark / .comic 变体块。
+    expect(variables).not.toMatch(/^\.dark\s*{/m)
+    expect(variables).not.toMatch(/^\.comic\s*{/m)
+  })
+
+  it('bridges CYBER tokens into Arco CSS variables', () => {
+    // 没有 ConfigProvider，Arco 的实际外观由 global.scss 里的 --color-* 覆盖决定。
+    const globalStyles = readClientFile('styles/global.scss')
+
+    expect(globalStyles).toContain('--color-primary: oklch(0.805 0.148 188);')
+    expect(globalStyles).toContain('--color-bg-1: oklch(0.155 0.012 250);')
+    expect(globalStyles).toContain('--color-border-1: oklch(0.305 0.018 242);')
   })
 
   it('exports the frozen Arco theme tokens', async () => {
@@ -30,17 +42,19 @@ describe('client style system', () => {
     expect(arcoTheme.colorBgLayout).toBeTruthy()
     expect(arcoTheme.colorBgContainer).toBeTruthy()
     expect(arcoTheme.borderRadius).toBeTypeOf('number')
-    expect(arcoTheme.fontFamily).toContain('Inter')
+    expect(arcoTheme.fontFamily).toContain('PingFang SC')
     expect(arcoTheme.fontFamilyMono).toContain('JetBrains Mono')
   })
 
-  it('carries dark mode through the arco-theme attribute on the root element', () => {
+  it('pins Arco to dark mode on the root element', () => {
     // 不 import useTheme：它在模块顶层读 localStorage，node 环境下会抛。
     // 断言源码契约即可，真实行为由 useTheme 自己的测试覆盖。
     const source = readClientFile('composables/useTheme.ts')
 
     expect(source).toContain("setAttribute('arco-theme'")
-    expect(source).toMatch(/'dark' : 'light'|'dark'|'light'/)
+    // 单主题：不再有 light / comic 变体，只固定 dark。
+    expect(source).not.toMatch(/classList\.toggle\(['"](dark|comic)/)
+    expect(source).not.toMatch(/localStorage\.getItem\(['"]hermes_(brightness|style)/)
   })
 
   it('keeps mobile inputs at 16px so iOS does not zoom on focus', () => {