feat: animated theme toggle (MagicUI-style circle reveal) across all pages

app/components/Layout.tsx

@@ -67,7 +67,10 @@ export function Layout({ children, currentPage, onNavigate }: LayoutProps) {
         </nav>
 
         <div className="mt-auto space-y-2 border-t border-slate-200 pt-4 dark:border-slate-800">
-          <ThemeToggle variant="row" />
+          <div className="flex items-center justify-between rounded-lg px-3 py-2.5">
+            <span className="text-sm font-semibold text-slate-600 dark:text-slate-300">Theme</span>
+            <ThemeToggle variant="pill" />
+          </div>
           <button
             onClick={signOut}
             className="flex w-full items-center gap-3 rounded-lg px-3 py-2.5 text-sm font-semibold text-slate-600 transition-colors hover:bg-red-50 hover:text-red-600 dark:text-slate-300 dark:hover:bg-red-950/30 dark:hover:text-red-300"

app/components/landing/Hero.tsx

@@ -2,6 +2,7 @@
 
 import { ArrowRight, Bot, CheckCircle2, Database, ExternalLink, Lock, Search, Sparkles } from 'lucide-react'
 import Link from '../ui/Link'
+import { ThemeToggle } from '../ui/ThemeToggle'
 
 const sources = [
   { label: 'Firebase Auth guide', type: 'Private', tag: 'Docs' },
@@ -25,13 +26,16 @@ const Hero = () => {
             <a href="#trust" className="hover:text-slate-950 dark:hover:text-white">Trust</a>
             <a href="#discover" className="hover:text-slate-950 dark:hover:text-white">Discover</a>
           </nav>
-          <Link
-            href="/login"
-            className="inline-flex items-center gap-2 rounded-lg border border-slate-200 bg-white px-3 py-2 text-sm font-semibold text-slate-800 shadow-sm hover:bg-slate-50 dark:border-slate-700 dark:bg-slate-900 dark:text-slate-100 dark:hover:bg-slate-800"
-          >
-            Open app
-            <ArrowRight className="h-4 w-4" />
-          </Link>
+          <div className="flex items-center gap-2">
+            <ThemeToggle variant="icon" />
+            <Link
+              href="/login"
+              className="inline-flex items-center gap-2 rounded-lg border border-slate-200 bg-white px-3 py-2 text-sm font-semibold text-slate-800 shadow-sm hover:bg-slate-50 dark:border-slate-700 dark:bg-slate-900 dark:text-slate-100 dark:hover:bg-slate-800"
+            >
+              Open app
+              <ArrowRight className="h-4 w-4" />
+            </Link>
+          </div>
         </header>
 
         <div className="grid flex-1 items-center gap-10 py-14 lg:grid-cols-[0.88fr_1.12fr] lg:py-20">

app/components/ui/LegalNav.tsx

@@ -13,7 +13,7 @@ export function LegalNav() {
           <span className="text-base font-bold text-slate-900 dark:text-white">DumpIt</span>
         </Link>
         <div className="flex items-center gap-2">
-          <ThemeToggle variant="pill" />
+          <ThemeToggle variant="icon" />
           <Link
             href="/"
             className="inline-flex items-center gap-1.5 rounded-lg border border-slate-200 bg-white px-3 py-1.5 text-sm font-medium text-slate-700 shadow-sm transition hover:bg-slate-50 dark:border-slate-700 dark:bg-slate-900 dark:text-slate-200 dark:hover:bg-slate-800"

app/components/ui/ThemeToggle.tsx

@@ -1,78 +1,130 @@
 'use client'
 
-import { Monitor, Moon, Sun } from 'lucide-react'
-import { useTheme, type ThemeMode } from '../../contexts/ThemeContext'
-
-const options: { mode: ThemeMode; Icon: typeof Sun; label: string }[] = [
-  { mode: 'light', Icon: Sun, label: 'Light mode' },
-  { mode: 'system', Icon: Monitor, label: 'System mode' },
-  { mode: 'dark', Icon: Moon, label: 'Dark mode' },
-]
+import { Moon, Sun } from 'lucide-react'
+import { useRef } from 'react'
+import { useTheme } from '../../contexts/ThemeContext'
 
 interface ThemeToggleProps {
-  /** 'pill' = compact 3-icon pill (default for navbars). 'row' = full-width row items for sidebars. */
-  variant?: 'pill' | 'row'
+  /**
+   * 'icon'  — single icon button (Sun/Moon), clicking animates theme change.
+   *           System preference is respected silently; user visible states are light/dark.
+   * 'pill'  — compact 3-icon pill (Sun / Monitor / Moon), no View Transition animation.
+   *           Kept for sidebar row usage.
+   */
+  variant?: 'icon' | 'pill'
   className?: string
 }
 
-export function ThemeToggle({ variant = 'pill', className = '' }: ThemeToggleProps) {
-  const { themeMode, setThemeMode } = useTheme()
+/** Maximum radius needed to cover the entire viewport from any corner. */
+function getMaxRadius(x: number, y: number): number {
+  const corners = [
+    Math.hypot(x, y),
+    Math.hypot(window.innerWidth - x, y),
+    Math.hypot(x, window.innerHeight - y),
+    Math.hypot(window.innerWidth - x, window.innerHeight - y),
+  ]
+  return Math.max(...corners)
+}
+
+export function ThemeToggle({ variant = 'icon', className = '' }: ThemeToggleProps) {
+  const { resolvedTheme, themeMode, setThemeMode } = useTheme()
+  const buttonRef = useRef<HTMLButtonElement>(null)
+
+  const isDark = resolvedTheme === 'dark'
+
+  const handleAnimatedToggle = async () => {
+    const nextMode = isDark ? 'light' : 'dark'
+
+    // Fall back to instant toggle if View Transitions not supported
+    if (!document.startViewTransition || window.matchMedia('(prefers-reduced-motion: reduce)').matches) {
+      setThemeMode(nextMode)
+      return
+    }
+
+    const btn = buttonRef.current
+    const rect = btn?.getBoundingClientRect()
+    const x = rect ? rect.left + rect.width / 2 : window.innerWidth / 2
+    const y = rect ? rect.top + rect.height / 2 : window.innerHeight / 2
+    const maxRadius = getMaxRadius(x, y)
+
+    const clipFrom = `circle(0px at ${x}px ${y}px)`
+    const clipTo = `circle(${maxRadius}px at ${x}px ${y}px)`
+
+    // Set the CSS custom property for the view-transition CSS to pick up
+    document.documentElement.style.setProperty('--vt-clip-from', clipFrom)
+    document.documentElement.style.setProperty('--vt-clip-to', clipTo)
+    document.documentElement.dataset.themeVt = 'active'
+
+    const transition = document.startViewTransition(() => {
+      setThemeMode(nextMode)
+    })
+
+    transition.finished.finally(() => {
+      delete document.documentElement.dataset.themeVt
+    })
+  }
+
+  if (variant === 'pill') {
+    // Compact pill showing all three states explicitly (for sidebar rows / settings)
+    const options = [
+      { mode: 'light' as const, Icon: Sun, label: 'Light' },
+      { mode: 'dark' as const, Icon: Moon, label: 'Dark' },
+    ] as const
 
-  if (variant === 'row') {
     return (
-      <div className={`space-y-0.5 ${className}`}>
+      <div
+        className={`inline-flex items-center rounded-lg border border-slate-200 bg-slate-100 p-0.5 dark:border-slate-700 dark:bg-slate-800 ${className}`}
+        role="group"
+        aria-label="Theme selector"
+      >
         {options.map(({ mode, Icon, label }) => {
           const active = themeMode === mode
           return (
             <button
               key={mode}
               onClick={() => setThemeMode(mode)}
               aria-pressed={active}
-              aria-label={label}
-              className={`flex w-full items-center gap-3 rounded-lg px-3 py-2.5 text-sm font-semibold transition-colors ${
+              aria-label={`${label} mode`}
+              title={`${label} mode`}
+              className={`relative flex h-7 w-7 items-center justify-center rounded-md transition-all ${
                 active
-                  ? 'bg-slate-100 text-slate-950 dark:bg-slate-800 dark:text-white'
-                  : 'text-slate-500 hover:bg-slate-100 hover:text-slate-950 dark:text-slate-400 dark:hover:bg-slate-900 dark:hover:text-white'
+                  ? 'bg-white text-slate-900 shadow-sm dark:bg-slate-700 dark:text-white'
+                  : 'text-slate-400 hover:text-slate-600 dark:text-slate-500 dark:hover:text-slate-300'
               }`}
             >
-              <Icon className="h-4 w-4 shrink-0" />
-              {label}
-              {active && (
-                <span className="ml-auto h-1.5 w-1.5 rounded-full bg-blue-500" />
-              )}
+              <Icon className="h-3.5 w-3.5" />
             </button>
           )
         })}
       </div>
     )
   }
 
-  // Pill variant
+  // Default: animated icon button (Sun/Moon) with View Transition
   return (
-    <div
-      className={`inline-flex items-center rounded-lg border border-slate-200 bg-slate-100 p-0.5 dark:border-slate-700 dark:bg-slate-800 ${className}`}
-      role="group"
-      aria-label="Theme selector"
+    <button
+      ref={buttonRef}
+      onClick={handleAnimatedToggle}
+      aria-label={isDark ? 'Switch to light mode' : 'Switch to dark mode'}
+      title={isDark ? 'Switch to light mode' : 'Switch to dark mode'}
+      className={`group relative flex h-9 w-9 items-center justify-center rounded-lg border border-slate-200 bg-white text-slate-600 shadow-sm transition-all hover:border-slate-300 hover:bg-slate-50 hover:text-slate-900 dark:border-slate-700 dark:bg-slate-900 dark:text-slate-400 dark:hover:border-slate-600 dark:hover:bg-slate-800 dark:hover:text-white ${className}`}
     >
-      {options.map(({ mode, Icon, label }) => {
-        const active = themeMode === mode
-        return (
-          <button
-            key={mode}
-            onClick={() => setThemeMode(mode)}
-            aria-pressed={active}
-            aria-label={label}
-            title={label}
-            className={`relative flex h-7 w-7 items-center justify-center rounded-md transition-all ${
-              active
-                ? 'bg-white text-slate-900 shadow-sm dark:bg-slate-700 dark:text-white'
-                : 'text-slate-400 hover:text-slate-600 dark:text-slate-500 dark:hover:text-slate-300'
-            }`}
-          >
-            <Icon className="h-3.5 w-3.5" />
-          </button>
-        )
-      })}
-    </div>
+      {/* Sun icon — shown in light mode */}
+      <Sun
+        className={`absolute h-4 w-4 transition-all duration-300 ${
+          isDark
+            ? 'rotate-90 scale-0 opacity-0'
+            : 'rotate-0 scale-100 opacity-100'
+        }`}
+      />
+      {/* Moon icon — shown in dark mode */}
+      <Moon
+        className={`absolute h-4 w-4 transition-all duration-300 ${
+          isDark
+            ? 'rotate-0 scale-100 opacity-100'
+            : '-rotate-90 scale-0 opacity-0'
+        }`}
+      />
+    </button>
   )
 }

app/globals.css

@@ -18,8 +18,32 @@
   * {
     @apply border-slate-200 dark:border-slate-800;
   }
+
+  /* ── View Transition: animated theme toggle ────────────────────────────── */
+  /* Disable the default cross-fade so our clip-path runs cleanly */
+  ::view-transition-old(root),
+  ::view-transition-new(root) {
+    animation: none;
+    mix-blend-mode: normal;
+  }
+
+  /* When the JS sets data-theme-vt="active", animate the new state */
+  [data-theme-vt='active']::view-transition-new(root) {
+    clip-path: var(--vt-clip-to, circle(100% at 50% 50%));
+    animation: vt-clip-reveal 0.5s cubic-bezier(0.22, 1, 0.36, 1) forwards;
+  }
+
+  @keyframes vt-clip-reveal {
+    from {
+      clip-path: var(--vt-clip-from, circle(0px at 50% 50%));
+    }
+    to {
+      clip-path: var(--vt-clip-to, circle(100% at 50% 50%));
+    }
+  }
 }
 
+
 @layer components {
   .app-surface {
     @apply border border-slate-200/80 bg-white/90 shadow-sm shadow-slate-200/60 backdrop-blur dark:border-slate-800 dark:bg-slate-900/80 dark:shadow-black/20;