:root { color-scheme: light; }
* { box-sizing: border-box; }
body { margin: 0; padding: 16px; background: #f3f5f8; color: #1f2933;
       font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; }
.card { max-width: 640px; margin: 24px auto; background: #fff; border: 1px solid #dadce0; border-radius: 12px;
        padding: 28px 24px; box-shadow: 0 2px 10px rgba(0,0,0,0.05); }
h1 { margin: 0 0 12px; font-size: 1.6rem; }
h2 { margin: 28px 0 8px; font-size: 1.1rem; }
.lead { margin: 0 0 18px; }
.notice { padding: 12px 14px; border-radius: 8px; background: #fff4e5; border: 1px solid #f5c98a; margin: 0 0 16px; }
.notice.error { background: #fdecea; border-color: #f5b5ae; color: #8a1c12; }
.code-form label { display: block; font-weight: 600; margin-bottom: 6px; }
.code-form input { width: 100%; font-size: 1.6rem; letter-spacing: 0.18em; text-transform: uppercase; text-align: center;
                   padding: 12px; border: 2px solid #9aa5b1; border-radius: 10px; margin-bottom: 12px; }
.code-form input:focus { outline: none; border-color: #1a73e8; }
.big { display: block; width: 100%; padding: 16px; font-size: 1.15rem; font-weight: 700; text-align: center;
       color: #fff; background: #1a73e8; border: 0; border-radius: 10px; cursor: pointer; text-decoration: none; }
.big:hover { background: #1558b0; }
.big.download { background: #188038; margin: 8px 0 6px; }
.big.download:hover { background: #12652b; }
.hint, .muted { color: #5f6b7a; font-size: 0.9rem; }
.what ol { padding-left: 22px; }
.what li { margin-bottom: 8px; }
.foot { margin: 28px 0 0; text-align: center; color: #8a94a1; font-size: 0.85rem; }
@media (max-width: 480px) { .card { margin: 8px auto; padding: 20px 16px; } h1 { font-size: 1.35rem; } }