feat: implement NotFound page with search functionality and UI components

feat: add Card, Input, and Label components for UI consistency
refactor: update Button component to include cursor pointer style

apps/web/src/app/not-found.tsx

@@ -0,0 +1,100 @@
+"use client"
+
+import { Button } from "@workspace/ui/components/button";
+import { Card, CardContent } from "@workspace/ui/components/card";
+import { Input } from "@workspace/ui/components/input";
+import { ArrowLeft, BookOpen, Home, Search } from "lucide-react";
+import Link from "next/link";
+import { useRouter } from "next/navigation";
+import { useState } from "react";
+
+export default function NotFound() {
+  const [searchQuery, setSearchQuery] = useState("")
+  const router = useRouter()
+
+  const handleSearch = (e: React.FormEvent) => {
+    e.preventDefault()
+    if (searchQuery.trim()) {
+      router.push(`/search?q=${encodeURIComponent(searchQuery.trim())}`)
+    }
+  }
+
+  return (
+    <div className="min-h-screen bg-gradient-to-br from-background via-background to-muted/20">
+      <div className="container mx-auto px-4 py-16">
+        <div className="max-w-4xl mx-auto">
+          {/* 404 Illustration */}
+          <div className="text-center mb-12">
+            <div className="relative mb-8">
+              <div className="text-9xl font-bold text-primary/20 select-none">404</div>
+              <div className="absolute inset-0 flex items-center justify-center">
+                <div className="w-32 h-32 bg-primary/10 rounded-full flex items-center justify-center">
+                  <BookOpen className="h-16 w-16 text-primary/60" />
+                </div>
+              </div>
+            </div>
+
+            <h1 className="text-4xl font-bold mb-4">Page Not Found</h1>
+            <p className="text-xl text-muted-foreground mb-8 max-w-2xl mx-auto">
+              Oops! The page you{"'"}re looking for seems to have wandered off into another dimension.
+              Don{"'"}t worry, we{"'"}ll help you find your way back to amazing stories!
+            </p>
+          </div>
+          {/* Search Section */}
+          <Card className="mb-12">
+            <CardContent className="p-8">
+              <div className="text-center mb-6">
+                <h2 className="text-2xl font-semibold mb-2">Search for Stories</h2>
+                <p className="text-muted-foreground">Looking for a specific novel? Try searching for it below.</p>
+              </div>
+
+              <form onSubmit={handleSearch} className="max-w-md mx-auto">
+                <div className="relative">
+                  <Search className="absolute left-3 top-1/2 transform -translate-y-1/2 h-4 w-4 text-muted-foreground" />
+                  <Input
+                    type="text"
+                    placeholder="Search novels, authors, genres..."
+                    value={searchQuery}
+                    onChange={(e) => setSearchQuery(e.target.value)}
+                    className="pl-10 pr-4 h-12 text-base"
+                  />
+                  <Button
+                    type="submit"
+                    className="absolute right-1 top-1/2 transform -translate-y-1/2 h-10"
+                    disabled={!searchQuery.trim()}
+                  >
+                    Search
+                  </Button>
+                </div>
+              </form>
+            </CardContent>
+          </Card>
+          {/* Action Buttons */}
+          <div className="flex flex-col sm:flex-row gap-4 justify-center items-center">
+            <Button onClick={() => router.back()} variant="outline" size="lg" className="gap-2">
+              <ArrowLeft className="h-4 w-4" />
+              Go Back
+            </Button>
+
+            <Link href="/">
+              <Button size="lg" className="gap-2">
+                <Home className="h-4 w-4" />
+                Return Home
+              </Button>
+            </Link>
+          </div>
+          {/* Help Text */}
+          <div className="text-center mt-12 text-sm text-muted-foreground">
+            <p>
+              Still can{"'"}t find what you{"'"}re looking for?{" "}
+              <Link href="/contact" className="text-primary hover:underline">
+                Contact our support team
+              </Link>{" "}
+              for assistance.
+            </p>
+          </div>
+        </div>
+      </div>
+    </div>
+  );
+}

packages/ui/src/components/button.tsx

@@ -5,7 +5,7 @@ import { cva, type VariantProps } from "class-variance-authority"
 import { cn } from "@workspace/ui/lib/utils"
 
 const buttonVariants = cva(
-  "inline-flex items-center justify-center gap-2 whitespace-nowrap rounded-md text-sm font-medium transition-[color,box-shadow] disabled:pointer-events-none disabled:opacity-50 [&_svg]:pointer-events-none [&_svg:not([class*='size-'])]:size-4 shrink-0 [&_svg]:shrink-0 outline-none focus-visible:border-ring focus-visible:ring-ring/50 focus-visible:ring-[3px] aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive",
+  "inline-flex items-center justify-center gap-2 whitespace-nowrap rounded-md text-sm font-medium transition-[color,box-shadow] disabled:pointer-events-none disabled:opacity-50 [&_svg]:pointer-events-none [&_svg:not([class*='size-'])]:size-4 shrink-0 [&_svg]:shrink-0 outline-none focus-visible:border-ring focus-visible:ring-ring/50 focus-visible:ring-[3px] aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive cursor-pointer",
   {
     variants: {
       variant: {

packages/ui/src/components/card.tsx

@@ -0,0 +1,92 @@
+import * as React from "react"
+
+import { cn } from "@workspace/ui/lib/utils"
+
+function Card({ className, ...props }: React.ComponentProps<"div">) {
+  return (
+    <div
+      data-slot="card"
+      className={cn(
+        "bg-card text-card-foreground flex flex-col gap-6 rounded-xl border py-6 shadow-sm",
+        className
+      )}
+      {...props}
+    />
+  )
+}
+
+function CardHeader({ className, ...props }: React.ComponentProps<"div">) {
+  return (
+    <div
+      data-slot="card-header"
+      className={cn(
+        "@container/card-header grid auto-rows-min grid-rows-[auto_auto] items-start gap-1.5 px-6 has-data-[slot=card-action]:grid-cols-[1fr_auto] [.border-b]:pb-6",
+        className
+      )}
+      {...props}
+    />
+  )
+}
+
+function CardTitle({ className, ...props }: React.ComponentProps<"div">) {
+  return (
+    <div
+      data-slot="card-title"
+      className={cn("leading-none font-semibold", className)}
+      {...props}
+    />
+  )
+}
+
+function CardDescription({ className, ...props }: React.ComponentProps<"div">) {
+  return (
+    <div
+      data-slot="card-description"
+      className={cn("text-muted-foreground text-sm", className)}
+      {...props}
+    />
+  )
+}
+
+function CardAction({ className, ...props }: React.ComponentProps<"div">) {
+  return (
+    <div
+      data-slot="card-action"
+      className={cn(
+        "col-start-2 row-span-2 row-start-1 self-start justify-self-end",
+        className
+      )}
+      {...props}
+    />
+  )
+}
+
+function CardContent({ className, ...props }: React.ComponentProps<"div">) {
+  return (
+    <div
+      data-slot="card-content"
+      className={cn("px-6", className)}
+      {...props}
+    />
+  )
+}
+
+function CardFooter({ className, ...props }: React.ComponentProps<"div">) {
+  return (
+    <div
+      data-slot="card-footer"
+      className={cn("flex items-center px-6 [.border-t]:pt-6", className)}
+      {...props}
+    />
+  )
+}
+
+export {
+  Card,
+  CardHeader,
+  CardFooter,
+  CardTitle,
+  CardAction,
+  CardDescription,
+  CardContent,
+}

packages/ui/src/components/input.tsx

@@ -0,0 +1,21 @@
+import * as React from "react"
+
+import { cn } from "@workspace/ui/lib/utils"
+
+function Input({ className, type, ...props }: React.ComponentProps<"input">) {
+  return (
+    <input
+      type={type}
+      data-slot="input"
+      className={cn(
+        "file:text-foreground placeholder:text-muted-foreground selection:bg-primary selection:text-primary-foreground dark:bg-input/30 border-input flex h-9 w-full min-w-0 rounded-md border bg-transparent px-3 py-1 text-base shadow-xs transition-[color,box-shadow] outline-none file:inline-flex file:h-7 file:border-0 file:bg-transparent file:text-sm file:font-medium disabled:pointer-events-none disabled:cursor-not-allowed disabled:opacity-50 md:text-sm",
+        "focus-visible:border-ring focus-visible:ring-ring/50 focus-visible:ring-[3px]",
+        "aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive",
+        className
+      )}
+      {...props}
+    />
+  )
+}
+
+export { Input }

packages/ui/src/components/label.tsx

@@ -0,0 +1,24 @@
+"use client"
+
+import * as React from "react"
+import * as LabelPrimitive from "@radix-ui/react-label"
+
+import { cn } from "@workspace/ui/lib/utils"
+
+function Label({
+  className,
+  ...props
+}: React.ComponentProps<typeof LabelPrimitive.Root>) {
+  return (
+    <LabelPrimitive.Root
+      data-slot="label"
+      className={cn(
+        "flex items-center gap-2 text-sm leading-none font-medium select-none group-data-[disabled=true]:pointer-events-none group-data-[disabled=true]:opacity-50 peer-disabled:cursor-not-allowed peer-disabled:opacity-50",
+        className
+      )}
+      {...props}
+    />
+  )
+}
+
+export { Label }