body{font-family:Arial,sans-serif;margin:0;background:#f0f2f5}.container{padding:20px;max-width:900px;margin:auto}nav{display:flex;gap:10px;margin-bottom:20px}nav button{flex:1;padding:10px;border:none;color:#fff;font-size:16px;cursor:pointer;border-radius:8px;transition:transform .2s}nav button:hover{transform:scale(1.05)}header{border-left:6px solid;padding-left:10px;margin-bottom:20px}.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:15px}.card{background:white;padding:15px;border:3px solid;border-radius:12px;box-shadow:0 2px 5px #0000001a;transition:transform .2s}.card:hover{transform:translateY(-5px)}