feat: Racing Cards landing page - Astro + Tailwind v4

- Mobile-first dark mode landing
- Lucide icons (zero emojis)
- Self-hostable (Dockerfile + nginx)
- 10 card images generated with Nano Banana 2
- Sections: Hero, How It Works, Card Gallery, Features, Early Access, Footer
- Simple HTML form (no Netlify dependency)
- Zero JS output, static HTML

package.json

@@ -0,0 +1,15 @@
+{
+  "name": "racing-cards-landing",
+  "type": "module",
+  "version": "1.0.0",
+  "scripts": {
+    "dev": "astro dev",
+    "build": "astro build",
+    "preview": "astro preview"
+  },
+  "dependencies": {
+    "@tailwindcss/vite": "^4.2.1",
+    "astro": "^5.18.0",
+    "tailwindcss": "^4.2.1"
+  }
+}