feat(ui): theme & layout improvements

- Dark-blue theme background assets and styling integration
- Appearance settings with layoutMode (full/compact) preference
- Settings dialog and auth context updates
- AI writing form and panel refinements
- Open Canvas context updates
- Roundtable planning styling and dashboard enhancements
- Strategy components and header updates
- Light app management and routing improvements
- Global style enhancements for dark theme
- Various page layout and workspace routing optimizations

frontend-web/src/open-canvas/components/ai-writing/AIWritingForm.tsx

@@ -47,7 +47,7 @@ const MATERIAL_SOURCE_OPTIONS: Array<{ value: MaterialSource; label: string; des
   { value: 'notebook', label: '我的空间', desc: '从空间中检索素材' },
 ];
 
-const FIELD_LABEL_CLASS = 'text-[16px] font-semibold leading-none text-[#222]';
+const FIELD_LABEL_CLASS = 'text-[16px] font-semibold leading-none text-[#222] dark:text-[#AACEFF]';
 const FIELD_TRIGGER_CLASS =
   'h-12 w-full rounded-xl border-[#e8dedd] bg-white text-sm shadow-sm';
 

frontend-web/src/open-canvas/components/ai-writing/AIWritingPanel.tsx

@@ -254,7 +254,7 @@ export function AIWritingPanel({
   const showNewButton = isHistoryMode || state.status !== 'idle';
 
   return (
-    <div className="flex flex-col h-full overflow-hidden bg-background">
+    <div className="flex flex-col h-full overflow-hidden bg-background dark:bg-transparent">
       {!isHistoryMode && (
         <DraftSync status={state.status} markdown={state.currentDraftMarkdown} title={state.currentDraftTitle} />
       )}

frontend-web/src/open-canvas/components/ai-writing/WritingSetupChat.tsx

@@ -114,7 +114,7 @@ export function WritingSetupChat() {
   return (
     <ThreadContext.Provider value={{ thread }}>
       <ArtifactsProvider>
-        <div className="flex size-full flex-col bg-background">
+        <div className="flex size-full flex-col bg-background dark:bg-transparent">
           {/* 空状态隐藏对话头部，直接展示欢迎屏（与原型图一致）；有消息后再显示头部 */}
           {!showWelcome && (
             <header className="flex shrink-0 items-center gap-2 border-b px-4 py-3">
@@ -139,7 +139,7 @@ export function WritingSetupChat() {
             )}
           </div>
 
-          <div className="bg-background shrink-0 border-t px-4 py-4">
+          <div className="bg-background dark:bg-transparent shrink-0 border-t px-4 py-4">
             {/* 与原型图一致：白色圆角卡片包裹「模型选择行 + 输入框」 */}
             <div className="space-y-3 rounded-2xl border border-[#ece5e4] bg-card p-3 shadow-sm dark:border-[#1B477E] dark:bg-[#022248]/40">
               <div className="flex items-center justify-between gap-3">

frontend-web/src/open-canvas/contexts/WritingFormContext.tsx

@@ -59,7 +59,7 @@ export function useWritingFormOptional(): WritingFormValue | null {
 export function WritingFormProvider({ children, initialMaterialSource }: { children: ReactNode; initialMaterialSource?: 'general' | 'notebook' }) {
   const [intent, setIntent] = useState('');
   const [formExpanded, setFormExpanded] = useState(false);
-  const [showOutline, setShowOutline] = useState(false);
+  const [showOutline, setShowOutline] = useState(true);
   const [outlineText, setOutlineText] = useState('');
   const [articleType, setArticleType] = useState('analysis');
   const [wordCountInput, setWordCountInput] = useState('800');

frontend-web/src/open-canvas/pages/AIWritingPage.tsx

@@ -229,7 +229,7 @@ export default function AIWritingPage({
       <AIWritingProvider>
       <WritingFormProvider initialMaterialSource={studioToken ?? initialNotebookId != null ? 'notebook' : undefined}>
       <TooltipProvider delayDuration={300}>
-        <div className="h-full flex flex-col overflow-hidden bg-background">
+        <div className="h-full flex flex-col overflow-hidden bg-background canvas-writing-bg">
           <div className="flex-1 min-h-0 overflow-hidden">
             <AIWritingLayout hideAdvancedFields={hideAdvancedFields} initialNotebookId={initialNotebookId} initialDocumentIds={initialDocumentIds} studioToken={studioToken} />
           </div>