body{margin:0;min-height:100dvh;display:grid;place-items:center;background:#10131e;color:#fff;font:16px/1.6 Arial,sans-serif}main{padding:24px;max-width:540px}h1{font-size:28px}button{background:#498bff;color:white;padding:12px 22px;border:0;border-radius:8px;cursor:pointer;font:inherit}button:focus-visible{outline:3px solid white;outline-offset:3px}