* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: -apple-system, "Microsoft YaHei", sans-serif;
  max-width: 800px;
  margin: 0 auto;
  padding: 20px;
  background: #f5f5f5;
  min-height: 100vh;
}
div { background: #fff; padding: 24px; border-radius: 8px; margin-bottom: 16px; }
h2 { margin-bottom: 16px; }
label { display: block; margin-bottom: 12px; }
input[type="text"] {
  width: 100%; padding: 10px; margin-top: 4px;
  border: 1px solid #ccc; border-radius: 4px;
}
button {
  padding: 10px 24px; background: #2563eb; color: #fff;
  border: none; border-radius: 4px; font-size: 16px; cursor: pointer;
  margin-top: 8px;
}
button:disabled { background: #ccc; cursor: not-allowed; }
#timer-display {
  font-size: 48px; font-weight: bold; text-align: center;
  color: #2563eb; margin-bottom: 16px;
}
#writing-area {
  width: 100%; height: 400px; padding: 12px;
  border: 1px solid #ccc; border-radius: 4px;
  font-size: 16px; line-height: 1.6; resize: vertical;
}
#submit-hint { margin-top: 8px; color: #888; font-size: 14px; }