:root { color-scheme: light dark; font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif; }
body { margin: 0; }
main { max-width: 28rem; margin: 4rem auto; padding: 0 1.25rem; line-height: 1.6; }
h1 { font-size: 1.5rem; }
form { display: grid; gap: 0.5rem; margin: 1.5rem 0; }
label { font-weight: 600; }
input { font: inherit; padding: 0.5rem 0.625rem; border: 1px solid #767676; border-radius: 6px; }
button { font: inherit; padding: 0.5rem 1rem; border: 0; border-radius: 6px; background: #0b57d0; color: #fff; cursor: pointer; }
button:focus-visible, input:focus-visible, a:focus-visible { outline: 3px solid #4c8df6; outline-offset: 2px; }
.alert { padding: 0.625rem 0.875rem; border-radius: 6px; background: #fde7e9; color: #8a1c1c; }
.hint { color: #595959; font-size: 0.9rem; }
dl { display: grid; grid-template-columns: max-content 1fr; gap: 0.25rem 1rem; }
dt { font-weight: 600; }
dd { margin: 0; }
@media (prefers-color-scheme: dark) {
  .alert { background: #4a1418; color: #ffd7d9; }
  .hint { color: #b3b3b3; }
}