* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; display: flex; align-items: center; justify-content: center; background: #f6f4ee; color: #0f1a2e;
  font: 15px/1.5 "Noto Sans TC", "Microsoft JhengHei", system-ui, sans-serif; padding: 16px; }
.box { width: 100%; max-width: 340px; background: #fff; border: 1px solid #e3ddcc; border-radius: 12px; padding: 24px; }
h1 { font-size: 20px; margin: 0 0 16px; color: #1e3366; }
label { display: block; font-size: 13px; color: #615a50; margin-bottom: 4px; }
input { width: 100%; font: inherit; padding: 10px; border: 1px solid #bfb9ab; border-radius: 8px; margin-bottom: 12px; }
button { width: 100%; font: inherit; padding: 10px; border: 0; border-radius: 8px; background: #1e3366; color: #fff; cursor: pointer; }
.err { color: #b23a3a; font-size: 13px; margin: 12px 0 0; }