body { margin: 0; padding: 24px 16px; background: #f6f6f6; color: #222; font: 16px/1.5 system-ui, sans-serif; }
main { max-width: 420px; margin: 0 auto; background: #fff; padding: 20px; text-align: left; }
.brand { background: #e8e8e8; padding: 8px 12px; font-size: 13px; margin-bottom: 24px; }
h1 { font-size: 22px; margin: 0 0 12px; }
p { margin: 0 0 16px; }
button { background: #333; color: #fff; border: 0; padding: 12px 18px; font: inherit; cursor: pointer; }
button:disabled { background: #bbb; cursor: default; }
button[hidden] { display: none; }
button:focus-visible { outline: 3px solid #1a73e8; outline-offset: 2px; }
#notice { background: #eee; padding: 10px 12px; font-size: 14px; margin-top: 16px; }
#notice:empty { display: none; }