update license and qol improvements

Signed-off-by: Avinal Kumar <avinal.xlvii@gmail.com>

src/pages/404.astro

@@ -0,0 +1,45 @@
+---
+import BaseLayout from "@/layouts/BaseLayout.astro";
+---
+
+<BaseLayout title="404 — Page Not Found" description="The page you're looking for doesn't exist.">
+  <div class="not-found">
+    <span class="nf-code">404</span>
+    <h1>Page not found</h1>
+    <p>The page you're looking for doesn't exist or has been moved.</p>
+    <a href="/" class="btn btn-accent">Back to home</a>
+  </div>
+</BaseLayout>
+
+<style>
+  .not-found {
+    display: flex;
+    flex-direction: column;
+    align-items: center;
+    justify-content: center;
+    text-align: center;
+    min-height: 50vh;
+    gap: var(--space-4);
+  }
+
+  .nf-code {
+    font-size: clamp(5rem, 15vw, 10rem);
+    font-weight: 800;
+    letter-spacing: -0.04em;
+    line-height: 1;
+    color: var(--border);
+  }
+
+  .not-found h1 {
+    font-size: var(--text-2xl);
+  }
+
+  .not-found p {
+    color: var(--text-muted);
+    max-width: 40ch;
+  }
+
+  .not-found .btn {
+    margin-top: var(--space-4);
+  }
+</style>