* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: #333;
  min-height: 100vh;
  line-height: 1.6;
}

.hero {
  text-align: center;
  padding: 60px 20px 40px;
  color: white;
}

.hero h1 {
  font-size: 2.5rem;
  margin-bottom: 12px;
}

.hero .subtitle {
  font-size: 1.1rem;
  opacity: 0.9;
  margin-bottom: 20px;
}

.hero-links {
  margin-top: 16px;
}

.btn {
  display: inline-block;
  padding: 12px 28px;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  border: none;
  transition: all 0.2s;
}

.btn-outline {
  background: rgba(255,255,255,0.15);
  color: white;
  border: 2px solid white;
  backdrop-filter: blur(10px);
}

.btn-outline:hover {
  background: white;
  color: #667eea;
}

.btn-primary {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  width: 100%;
  padding: 14px;
  font-size: 1.05rem;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(102,126,234,0.4);
}

.btn-primary:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

main {
  max-width: 960px;
  margin: 0 auto;
  padding: 0 20px 60px;
}

section {
  background: white;
  border-radius: 16px;
  padding: 36px;
  margin-bottom: 30px;
  box-shadow: 0 10px 40px rgba(0,0,0,0.1);
}

section h2 {
  font-size: 1.5rem;
  margin-bottom: 20px;
  color: #2d3748;
}

/* 三栏卡片 */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
}

.card {
  border-radius: 12px;
  padding: 24px;
  border: 2px solid #e2e8f0;
  transition: transform 0.2s;
}

.card:hover {
  transform: translateY(-4px);
}

.card h3 {
  font-size: 1.2rem;
  margin-bottom: 12px;
}

.card ul {
  list-style: none;
  margin-bottom: 16px;
}

.card ul li {
  padding: 6px 0;
  padding-left: 20px;
  position: relative;
  font-size: 0.95rem;
}

.card ul li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: #48bb78;
  font-weight: bold;
}

.card-basic { border-color: #48bb78; }
.card-basic h3 { color: #2f855a; }
.card-advanced { border-color: #4299e1; }
.card-advanced h3 { color: #2b6cb0; }
.card-annotated { border-color: #ed8936; }
.card-annotated h3 { color: #c05621; }

.status {
  text-align: center;
  padding: 8px;
  border-radius: 6px;
  font-weight: 600;
  font-size: 0.9rem;
}

.status.public {
  background: #c6f6d5;
  color: #22543d;
}

.status.gated {
  background: #fed7d7;
  color: #742a2a;
}

/* 表单 */
.form-hint {
  color: #718096;
  margin-bottom: 24px;
  font-size: 0.95rem;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.form-group {
  margin-bottom: 18px;
}

.form-group label {
  display: block;
  margin-bottom: 6px;
  font-weight: 600;
  color: #4a5568;
  font-size: 0.9rem;
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 10px 14px;
  border: 2px solid #e2e8f0;
  border-radius: 8px;
  font-size: 0.95rem;
  font-family: inherit;
  transition: border-color 0.2s;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: #667eea;
}

.form-result {
  margin-top: 16px;
  padding: 16px;
  border-radius: 8px;
  text-align: center;
  font-weight: 500;
}

.form-result.success {
  background: #c6f6d5;
  color: #22543d;
}

.form-result.error {
  background: #fed7d7;
  color: #742a2a;
}

footer {
  text-align: center;
  padding: 30px 20px;
  color: rgba(255,255,255,0.8);
  font-size: 0.9rem;
}

footer a {
  color: white;
  text-decoration: underline;
}

@media (max-width: 640px) {
  .hero h1 { font-size: 1.8rem; }
  section { padding: 24px; }
  .form-row { grid-template-columns: 1fr; }
}