:root {
  --accent: #2563eb;
  --bg: #f8fafc;
  --card-bg: #ffffff;
  --text: #1e293b;
  --muted: #64748b;
  --good: #16a34a;
  --bad: #dc2626;
}
* { box-sizing: border-box; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  margin: 0;
  padding: 16px;
}
.card {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 20px;
  max-width: 640px;
  margin: 0 auto 16px auto;
  box-shadow: 0 1px 3px rgba(0,0,0,0.08);
}
h1 { font-size: 1.4rem; margin-top: 0; }
h2 { font-size: 1.15rem; }
p { line-height: 1.5; }
.btn {
  display: block;
  text-align: center;
  background: var(--accent);
  color: white;
  padding: 12px 16px;
  border-radius: 8px;
  text-decoration: none;
  margin-top: 12px;
  font-weight: 600;
  border: none;
  width: 100%;
  cursor: pointer;
  font-size: 1rem;
}
.btn.secondary { background: #64748b; }
input[type=text], input[type=password], textarea {
  width: 100%;
  padding: 10px;
  border-radius: 8px;
  border: 1px solid #cbd5e1;
  font-size: 1rem;
  margin-bottom: 8px;
}
textarea { min-height: 120px; }
.mcq-option {
  display: block;
  padding: 10px 12px;
  border: 1px solid #cbd5e1;
  border-radius: 8px;
  margin-bottom: 6px;
  cursor: pointer;
}
.mcq-option.selected { border-color: var(--accent); background: #eff6ff; }
.progress-dots { display: flex; gap: 6px; margin-bottom: 12px; }
.progress-dots span { width: 10px; height: 10px; border-radius: 50%; background: #e2e8f0; }
.progress-dots span.active { background: var(--accent); }
.badge { display: inline-block; padding: 2px 8px; border-radius: 999px; font-size: 0.75rem; font-weight: 600; }
.badge.good { background: #dcfce7; color: var(--good); }
.badge.bad { background: #fee2e2; color: var(--bad); }
.muted { color: var(--muted); font-size: 0.9rem; }
.zh { color: var(--muted); font-size: 0.9rem; margin-top: 2px; }