Add dark mode, tooltips, and fix column alignment

web/src/components/ThemeProvider.tsx

@@ -0,0 +1,73 @@
+import React, { createContext, useContext, useEffect, useState } from 'react'
+
+type Theme = 'dark' | 'light' | 'system'
+
+type ThemeProviderProps = {
+  children: React.ReactNode
+  defaultTheme?: Theme
+  storageKey?: string
+}
+
+type ThemeProviderState = {
+  theme: Theme
+  setTheme: (theme: Theme) => void
+}
+
+const initialState: ThemeProviderState = {
+  theme: 'system',
+  setTheme: () => null,
+}
+
+const ThemeProviderContext = createContext<ThemeProviderState>(initialState)
+
+export function ThemeProvider({
+  children,
+  defaultTheme = 'system',
+  storageKey = 'vite-ui-theme',
+  ...props
+}: ThemeProviderProps) {
+  const [theme, setTheme] = useState<Theme>(
+    () => (localStorage.getItem(storageKey) as Theme) || defaultTheme
+  )
+
+  useEffect(() => {
+    const root = window.document.documentElement
+
+    root.classList.remove('light', 'dark')
+
+    if (theme === 'system') {
+      const systemTheme = window.matchMedia('(prefers-color-scheme: dark)')
+        .matches
+        ? 'dark'
+        : 'light'
+
+      root.classList.add(systemTheme)
+      return
+    }
+
+    root.classList.add(theme)
+  }, [theme])
+
+  const value = {
+    theme,
+    setTheme: (theme: Theme) => {
+      localStorage.setItem(storageKey, theme)
+      setTheme(theme)
+    },
+  }
+
+  return (
+    <ThemeProviderContext.Provider {...props} value={value}>
+      {children}
+    </ThemeProviderContext.Provider>
+  )
+}
+
+export const useTheme = () => {
+  const context = useContext(ThemeProviderContext)
+
+  if (context === undefined)
+    throw new Error('useTheme must be used within a ThemeProvider')
+
+  return context
+}

web/src/components/ThemeToggle.tsx

@@ -0,0 +1,21 @@
+import React from 'react'
+import { Moon, Sun } from 'lucide-react'
+import { Button } from './ui/button'
+import { useTheme } from './ThemeProvider'
+
+export function ThemeToggle() {
+  const { theme, setTheme } = useTheme()
+
+  return (
+    <Button
+      variant="outline"
+      size="icon"
+      onClick={() => setTheme(theme === 'light' ? 'dark' : 'light')}
+      className="relative"
+    >
+      <Sun className="h-[1.2rem] w-[1.2rem] rotate-0 scale-100 transition-all dark:-rotate-90 dark:scale-0" />
+      <Moon className="absolute h-[1.2rem] w-[1.2rem] rotate-90 scale-0 transition-all dark:rotate-0 dark:scale-100" />
+      <span className="sr-only">Toggle theme</span>
+    </Button>
+  )
+}

web/src/components/VideoClassifierApp.tsx

@@ -3,6 +3,8 @@ import { VirtualTable } from './VirtualTable';
 import { SearchAndFilter } from './SearchAndFilter';
 import { StatsOverview } from './StatsOverview';
 import { Button } from './ui/button';
+import { ThemeProvider } from './ThemeProvider';
+import { ThemeToggle } from './ThemeToggle';
 import type { VideoData } from '../types/video';
 import { searchVideos, filterVideos } from '../utils/search';
 
@@ -56,74 +58,79 @@ export default function VideoClassifierApp({ videos }: { videos: VideoData[] })
   }
 
   return (
-    <div className="min-h-screen bg-background">
-      <div className="container mx-auto px-6 py-8 space-y-8">
-        {/* Header */}
-        <div className="text-center space-y-4">
-          <h1 className="text-4xl font-bold bg-gradient-to-r from-primary to-primary/60 bg-clip-text text-transparent">
-            YouTube Video Classifier
-          </h1>
-          <p className="text-muted-foreground max-w-2xl mx-auto">
-            AI-powered video classification and management platform. Search, filter, and organize your YouTube video collection with intelligent categorization.
-          </p>
-        </div>
-
-        {/* Stats Overview */}
-        {videos.length > 0 && (
-          <StatsOverview data={videos} />
-        )}
-
-        {/* Search and Filter */}
-        {videos.length > 0 && (
-          <SearchAndFilter
-            data={videos}
-            searchTerm={searchTerm}
-            onSearchChange={setSearchTerm}
-            filters={filters}
-            onFilterChange={setFilters}
-            totalResults={videos.length}
-            filteredResults={filteredData.length}
-          />
-        )}
-
-        {/* Results */}
-        {videos.length > 0 ? (
-          filteredData.length > 0 ? (
-            <VirtualTable data={filteredData} />
-          ) : (
-            <div className="text-center py-12">
-              <div className="text-6xl mb-4">🔍</div>
-              <h3 className="text-lg font-medium mb-2">No results found</h3>
-              <p className="text-muted-foreground">
-                Try adjusting your search terms or filters
-              </p>
+    <ThemeProvider defaultTheme="system" storageKey="video-classifier-theme">
+      <div className="min-h-screen bg-background">
+        <div className="container mx-auto px-6 py-8 space-y-8">
+          {/* Header */}
+          <div className="text-center space-y-4">
+            <div className="flex items-center justify-center gap-4">
+              <h1 className="text-4xl font-bold bg-gradient-to-r from-primary to-primary/60 bg-clip-text text-transparent">
+                YouTube Video Classifier
+              </h1>
+              <ThemeToggle />
             </div>
-          )
-        ) : (
-          <div className="text-center py-12">
-            <div className="text-6xl mb-4">📹</div>
-            <h3 className="text-lg font-medium mb-2">No videos found</h3>
-            <p className="text-muted-foreground">
-              Your CSV file appears to be empty
+            <p className="text-muted-foreground max-w-2xl mx-auto">
+              AI-powered video classification and management platform. Search, filter, and organize your YouTube video collection with intelligent categorization.
             </p>
           </div>
-        )}
 
-        {/* Footer */}
-        <div className="text-center text-sm text-muted-foreground border-t pt-8">
-          <p>
-            {videos.length} videos indexed
-          </p>
-          <Button
-            variant="ghost"
-            size="sm"
-            onClick={() => window.location.reload}
-            className="mt-2"
-          >
-            Refresh Data
-          </Button>
+          {/* Stats Overview */}
+          {videos.length > 0 && (
+            <StatsOverview data={videos} />
+          )}
+
+          {/* Search and Filter */}
+          {videos.length > 0 && (
+            <SearchAndFilter
+              data={videos}
+              searchTerm={searchTerm}
+              onSearchChange={setSearchTerm}
+              filters={filters}
+              onFilterChange={setFilters}
+              totalResults={videos.length}
+              filteredResults={filteredData.length}
+            />
+          )}
+
+          {/* Results */}
+          {videos.length > 0 ? (
+            filteredData.length > 0 ? (
+              <VirtualTable data={filteredData} />
+            ) : (
+              <div className="text-center py-12">
+                <div className="text-6xl mb-4">🔍</div>
+                <h3 className="text-lg font-medium mb-2">No results found</h3>
+                <p className="text-muted-foreground">
+                  Try adjusting your search terms or filters
+                </p>
+              </div>
+            )
+          ) : (
+            <div className="text-center py-12">
+              <div className="text-6xl mb-4">📹</div>
+              <h3 className="text-lg font-medium mb-2">No videos found</h3>
+              <p className="text-muted-foreground">
+                Your CSV file appears to be empty
+              </p>
+            </div>
+          )}
+
+          {/* Footer */}
+          <div className="text-center text-sm text-muted-foreground border-t pt-8">
+            <p>
+              {videos.length} videos indexed
+            </p>
+            <Button
+              variant="ghost"
+              size="sm"
+              onClick={() => window.location.reload}
+              className="mt-2"
+            >
+              Refresh Data
+            </Button>
+          </div>
         </div>
       </div>
-    </div>
+    </ThemeProvider>
   );
 }

web/src/components/VirtualTable.tsx

@@ -4,6 +4,7 @@ import type { VideoData } from '../types/video';
 import { formatDuration, formatDate } from '../utils/csvParser';
 import { Badge } from './ui/badge';
 import { Button } from './ui/button';
+import { Tooltip } from './ui/tooltip';
 
 interface VirtualTableProps {
   data: VideoData[];
@@ -25,15 +26,15 @@ export function VirtualTable({ data }: VirtualTableProps) {
   return (
     <div className="border rounded-lg overflow-hidden">
       {/* Table Header */}
-      <div className="bg-muted/50 border-b p-4">
-        <div className="grid grid-cols-12 gap-4 text-sm font-medium text-muted-foreground">
-          <div className="col-span-2">Video</div>
-          <div className="col-span-2">Channel</div>
-          <div className="col-span-2">Classification</div>
-          <div className="col-span-2">Language</div>
-          <div className="col-span-1">Duration</div>
-          <div className="col-span-2">Date</div>
-          <div className="col-span-1">Actions</div>
+      <div className="bg-muted/50 border-b">
+        <div className="grid grid-cols-12 gap-3 px-4 py-3 text-sm font-medium text-muted-foreground">
+          <div className="col-span-3 flex items-center">Video</div>
+          <div className="col-span-2 flex items-center">Channel</div>
+          <div className="col-span-2 flex items-center">Classification</div>
+          <div className="col-span-1 flex items-center">Language</div>
+          <div className="col-span-1 flex items-center">Duration</div>
+          <div className="col-span-2 flex items-center">Date</div>
+          <div className="col-span-1 flex items-center">Actions</div>
         </div>
       </div>
 
@@ -69,51 +70,66 @@ export function VirtualTable({ data }: VirtualTableProps) {
                   transform: `translateY(${virtualItem.start}px)`,
                 }}
               >
-                <div className="border-b p-4 hover:bg-muted/50 transition-colors">
-                  <div className="grid grid-cols-12 gap-4 items-center">
+                <div className="border-b hover:bg-muted/50 transition-colors">
+                  <div className="grid grid-cols-12 gap-3 px-4 py-3 items-center min-h-[80px]">
                     {/* Video Info */}
-                    <div className="col-span-2 space-y-1">
-                      <h3 className="font-medium text-sm leading-tight line-clamp-2">
-                        {video.video_title}
-                      </h3>
+                    <div className="col-span-3 space-y-2 min-w-0">
+                      <Tooltip content={video.video_title}>
+                        <h3 className="font-medium text-sm leading-tight truncate">
+                          {video.video_title}
+                        </h3>
+                      </Tooltip>
                       <div className="flex flex-wrap gap-1">
-                        {video.detailed_subtags.split(',').slice(0, 3).map((tag, i) => (
-                          <Badge key={i} variant="secondary" className="text-xs">
-                            {tag.trim()}
-                          </Badge>
+                        {video.detailed_subtags.split(',').slice(0, 2).map((tag, i) => (
+                          <Tooltip key={i} content={tag.trim()}>
+                            <Badge variant="secondary" className="text-xs max-w-20 truncate">
+                              {tag.trim()}
+                            </Badge>
+                          </Tooltip>
                         ))}
+                        {video.detailed_subtags.split(',').length > 2 && (
+                          <Tooltip content={`+${video.detailed_subtags.split(',').length - 2} more tags`}>
+                            <Badge variant="outline" className="text-xs">
+                              +{video.detailed_subtags.split(',').length - 2}
+                            </Badge>
+                          </Tooltip>
+                        )}
                       </div>
                     </div>
 
                     {/* Channel */}
-                    <div className="col-span-2">
-                      <div className="text-sm font-medium">{video.channel_name}</div>
-                      <div className="text-xs text-muted-foreground">{video.playlist_name}</div>
+                    <div className="col-span-2 min-w-0">
+                      <Tooltip content={video.channel_name}>
+                        <div className="text-sm font-medium truncate">{video.channel_name}</div>
+                      </Tooltip>
+                      <Tooltip content={video.playlist_name}>
+                        <div className="text-xs text-muted-foreground truncate">{video.playlist_name}</div>
+                      </Tooltip>
                     </div>
 
                     {/* Classification */}
-                    <div className="col-span-2">
-                      <Badge variant="default" className="text-xs">
+                    <div className="col-span-2 min-w-0">
+                      <Badge variant="default" className="text-xs truncate max-w-full">
                         {video.classification}
                       </Badge>
                     </div>
 
                     {/* Language */}
-                    <div className="col-span-2">
-                      <Badge variant="outline" className="text-xs">
+                    <div className="col-span-1 min-w-0">
+                      <Badge variant="outline" className="text-xs truncate max-w-full">
                         {video.language}
                       </Badge>
                     </div>
 
                     {/* Duration */}
-                    <div className="col-span-1 text-sm">
+                    <div className="col-span-1 text-sm font-mono">
                       {formatDuration(video.video_length_seconds)}
                     </div>
 
                     {/* Date */}
-                    <div className="col-span-2 space-y-1">
+                    <div className="col-span-2 space-y-1 min-w-0">
                       <div className="text-sm">{formatDate(video.video_date)}</div>
-                      <div className="text-xs text-muted-foreground">
+                      <div className="text-xs text-muted-foreground truncate">
                         Added: {formatDate(video.timestamp)}
                       </div>
                     </div>
@@ -138,7 +154,7 @@ export function VirtualTable({ data }: VirtualTableProps) {
       </div>
 
       {/* Footer */}
-      <div className="bg-muted/50 border-t p-4">
+      <div className="bg-muted/50 border-t px-4 py-3">
         <div className="text-sm text-muted-foreground text-center">
           Showing {data.length} videos
         </div>

web/src/components/ui/tooltip.tsx

@@ -0,0 +1,36 @@
+import * as React from "react"
+import { cn } from "@/lib/utils"
+
+interface TooltipProps {
+  content: string
+  children: React.ReactNode
+  className?: string
+}
+
+export function Tooltip({ content, children, className }: TooltipProps) {
+  const [isVisible, setIsVisible] = React.useState(false)
+
+  return (
+    <div className="relative inline-block">
+      <div
+        onMouseEnter={() => setIsVisible(true)}
+        onMouseLeave={() => setIsVisible(false)}
+        className="cursor-help"
+      >
+        {children}
+      </div>
+      {isVisible && (
+        <div className={cn(
+          "absolute z-50 px-3 py-2 text-sm text-white bg-gray-900 dark:bg-gray-700 rounded-lg shadow-lg",
+          "bottom-full left-1/2 transform -translate-x-1/2 mb-2",
+          "max-w-xs break-words",
+          "before:content-[''] before:absolute before:top-full before:left-1/2 before:transform before:-translate-x-1/2",
+          "before:border-4 before:border-transparent before:border-t-gray-900 dark:before:border-t-gray-700",
+          className
+        )}>
+          {content}
+        </div>
+      )}
+    </div>
+  )
+}