body{background:#f9f9f9;margin:0;padding:0;font-family:Arial,sans-serif}header{color:#fff;background:#333;justify-content:space-between;padding:1rem;display:flex}header a{color:#fff;margin-left:1rem;text-decoration:none}main{padding:2rem}.grid{grid-template-columns:repeat(auto-fit,minmax(300px,1fr));gap:1rem;display:grid}.card{background:#fff;border-radius:8px;padding:1rem;box-shadow:0 2px 4px #0000001a}.btn{color:#fff;cursor:pointer;background:#28a745;border:none;border-radius:4px;padding:.5rem 1rem;display:inline-block}