style: sync xinyuan shell palette with rectification baseline

docs/ui-architecture.md

 # AI 应用 UI 架构
 
+## 2026-09-28 Shell 配色
+
+- AppShell 使用中性灰白内容画布与低饱和深藏蓝 Sidebar；侧栏红色 Logo 直接显示。配色来源与导航状态约定见 `docs/xinyuan-design-system.md`。
+- 此调整仅涉及 Shell 视觉层，不改变 Sidebar 路由、通知入口、页面状态或业务数据协议。
+
 ## 分层
 
 ```text

docs/xinyuan-design-system.md

@@ -4,6 +4,10 @@
 
 本项目以已确认的“问题整改”应用为唯一可执行视觉与交互基准，并使用鑫元 Skill 的 HeroUI 权威主题和共享 Tokens。页面不得自行近似组件外观。
 
+## 2026-09-28 Shell 配色
+
+AppShell 采用中性灰白内容画布与低饱和深藏蓝 Sidebar。页面画布由 `theme.css` 的 `--background: oklch(97.4% 0.002 255)` 提供；侧栏背景为 `oklch(32% 0.037 255)`。桌面和移动侧栏共用 `--xinyuan-sidebar-*`，选中导航为提亮的蓝色底与白字，侧栏红色 Logo 直接显示、不加底色；页面仍固定浅色，不提供主题切换。内容画布在 AppShell 顶部使用 4% 侧栏蓝色与 `--background` 混合的轻微渐变，至 18rem 淡出到灰白底色；Navbar 和滚动区共用这一层，页面 Card 与 HeroUI 组件保持原有表面 Token。当前导航使用较亮的同色系底色，普通导航悬停不覆盖选中态。
+
 全局 CSS 顺序固定为：
 
 ```css

src/components/DashboardSidebar.jsx

-import xyLogoWhite from '@/assets/xy-logo-white.png';
+import xyLogoRed from '@/assets/xy-logo-red.png';
 import { APPLICATION_DISPLAY_NAME } from '@/config/application';
 import { Sheet } from '@heroui-pro/react';
 import { Sidebar, useSidebar } from '@heroui-pro/react/sidebar';
@@ -127,7 +127,7 @@ function SidebarContents({
       <Sidebar.Header>
         <div className="app-sidebar-brand rc-sidebar-brand">
           <div className="app-sidebar-brand-mark rc-sidebar-brand-mark">
-            <img alt="鑫元" className="rc-sidebar-logo" src={xyLogoWhite} />
+            <img alt="鑫元" className="rc-sidebar-logo" src={xyLogoRed} />
           </div>
           <div
             className="app-sidebar-brand-main rc-sidebar-brand-main"

src/design-system/shell.css

@@ -400,7 +400,7 @@
 
 .app-shell-content-scroll {
   min-width: 0;
-  background: var(--rc-bg-canvas);
+  background: transparent;
   overscroll-behavior: contain;
 }
 
@@ -1172,7 +1172,11 @@
   overflow: hidden;
   border: 0;
   border-radius: 0;
-  background: var(--rc-bg-canvas);
+  background: linear-gradient(
+    180deg,
+    var(--xinyuan-canvas-top) 0,
+    var(--rc-bg-canvas) 18rem
+  );
 }
 
 .dark .rc-app-main.sidebar__main,
@@ -1602,7 +1606,7 @@
   }
 }
 
-/* Fixed split-shell theme: dark navigation, permanently light content canvas. */
+/* Muted navy navigation beside the permanently light content canvas. */
 .template-dashboard-shell .app-sidebar-glass,
 .rc-mobile-sidebar.app-sidebar-glass {
   color: var(--rc-sidebar-foreground);
@@ -1636,13 +1640,17 @@
   color: var(--rc-sidebar-item-selected-foreground) !important;
 }
 
-.template-dashboard-shell .sidebar__menu-item:hover .sidebar__menu-item-content,
 .template-dashboard-shell
-  .sidebar__menu-item[data-hovered='true']
+  .sidebar__menu-item:not([data-current='true']):hover
+  .sidebar__menu-item-content,
+.template-dashboard-shell
+  .sidebar__menu-item:not([data-current='true'])[data-hovered='true']
   .sidebar__menu-item-content,
-.rc-mobile-sidebar .sidebar__menu-item:hover .sidebar__menu-item-content,
 .rc-mobile-sidebar
-  .sidebar__menu-item[data-hovered='true']
+  .sidebar__menu-item:not([data-current='true']):hover
+  .sidebar__menu-item-content,
+.rc-mobile-sidebar
+  .sidebar__menu-item:not([data-current='true'])[data-hovered='true']
   .sidebar__menu-item-content,
 .app-sidebar-user-trigger.dropdown__trigger:hover,
 .app-sidebar-user-trigger.dropdown__trigger[data-hovered='true'] {

src/design-system/theme.css

@@ -32,7 +32,12 @@
   --primary-800: #941711;
   --primary-900: #73120d;
   --primary-950: #4a0c08;
-  --background: oklch(97.02% 0 29.2);
+  --background: oklch(97.4% 0.002 255);
+  --xinyuan-canvas-top: color-mix(
+    in oklab,
+    var(--xinyuan-sidebar-background) 4%,
+    var(--background)
+  );
   --border: oklch(90% 0 29.2);
   --danger: #b51b14;
   --danger-hover: #941711;
@@ -73,18 +78,17 @@
   --font-sans: var(--font-inter);
 
   /*
-   * Xinyuan fixed split-shell contract.
-   * The application canvas always uses this light theme. The Sidebar is the
-   * only persistent dark plane and must consume these semantic tokens.
+   * Xinyuan fixed light canvas with a muted navy Sidebar.
+   * Navigation colors are kept separate from HeroUI surfaces.
    */
-  --xinyuan-sidebar-background: oklch(16% 0.02 255);
-  --xinyuan-sidebar-border: oklch(26% 0.022 255);
-  --xinyuan-sidebar-foreground: oklch(97% 0.004 255);
-  --xinyuan-sidebar-muted: oklch(76% 0.018 255);
-  --xinyuan-sidebar-item-hover: oklch(22% 0.026 255);
-  --xinyuan-sidebar-item-selected: oklch(28% 0.016 255);
+  --xinyuan-sidebar-background: oklch(32% 0.037 255);
+  --xinyuan-sidebar-border: oklch(41% 0.036 255);
+  --xinyuan-sidebar-foreground: oklch(97% 0.005 255);
+  --xinyuan-sidebar-muted: oklch(82% 0.018 255);
+  --xinyuan-sidebar-item-hover: oklch(39% 0.042 255);
+  --xinyuan-sidebar-item-selected: oklch(46% 0.055 255);
   --xinyuan-sidebar-item-selected-foreground: oklch(99% 0.002 255);
-  --xinyuan-sidebar-focus: oklch(78% 0.105 29.2);
+  --xinyuan-sidebar-focus: oklch(85% 0.07 255);
 
   /*
    * ECharts is the required chart renderer for Xinyuan applications.

src/design-system/tokens.css

@@ -26,7 +26,7 @@
   --rc-text-muted: var(--muted);
   --rc-text-empty: color-mix(in oklab, var(--muted) 72%, var(--background));
 
-  /* Fixed dark Sidebar aliases. The content canvas remains light. */
+  /* Muted navy Sidebar aliases. The content canvas remains light. */
   --rc-sidebar-background: var(--xinyuan-sidebar-background);
   --rc-sidebar-border: var(--xinyuan-sidebar-border);
   --rc-sidebar-foreground: var(--xinyuan-sidebar-foreground);