/* ============ 基础 ============ */
:root {
  --bg: #fafafa;
  --card: #ffffff;
  --text: #1a1a2e;
  --muted: #6b7280;
  --primary: #4f46e5;
  --primary-dark: #4338ca;
  --border: #e5e7eb;
  --ok: #059669;
  --err: #dc2626;
  --radius: 12px;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }
.container { max-width: 1080px; margin: 0 auto; padding: 0 24px; }

/* ============ 导航 ============ */
nav {
  background: var(--card);
  border-bottom: 1px solid var(--border);
  padding: 14px 0;
}
nav .container { display: flex; align-items: center; justify-content: space-between; }
.logo { font-weight: 700; font-size: 18px; color: var(--text); }
nav .links a { margin-left: 20px; color: var(--muted); font-size: 14px; }

/* ============ Hero ============ */
.hero { text-align: center; padding: 80px 0 60px; }
.hero h1 { font-size: 40px; line-height: 1.2; margin-bottom: 16px; }
.hero p { font-size: 18px; color: var(--muted); max-width: 640px; margin: 0 auto 32px; }

/* ============ 按钮 ============ */
.btn {
  display: inline-block; padding: 12px 28px; border-radius: var(--radius);
  font-size: 16px; font-weight: 600; cursor: pointer; border: none;
  transition: background .15s ease;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-outline { background: transparent; color: var(--primary); border: 1px solid var(--primary); }
.btn-outline:hover { background: #eef2ff; }
.btn:disabled { opacity: .5; cursor: not-allowed; }

/* ============ 区块 ============ */
section { padding: 56px 0; }
section h2 { font-size: 28px; text-align: center; margin-bottom: 40px; }

/* ============ 特性 ============ */
.features { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 20px; }
.feature {
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 24px;
}
.feature h3 { margin-bottom: 8px; font-size: 17px; }
.feature p { color: var(--muted); font-size: 14px; }

/* ============ 定价卡片 ============ */
.pricing { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 24px; align-items: stretch; }
.price-card {
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 32px 28px; text-align: center;
  display: flex; flex-direction: column; gap: 12px;
  position: relative;
}
.price-card.featured { border: 2px solid var(--primary); box-shadow: 0 8px 30px rgba(79,70,229,.12); }
.price-card .badge {
  position: absolute; top: -12px; left: 50%; transform: translateX(-50%);
  background: var(--primary); color: #fff; font-size: 12px; font-weight: 600;
  padding: 3px 14px; border-radius: 999px;
}
.price-card h3 { font-size: 18px; }
.price-card .price { font-size: 36px; font-weight: 700; }
.price-card .price small { font-size: 14px; color: var(--muted); font-weight: 400; }
.price-card ul { list-style: none; text-align: left; margin: 8px 0 16px; flex: 1; }
.price-card ul li { padding: 6px 0; font-size: 14px; color: var(--muted); }
.price-card ul li::before { content: "✓ "; color: var(--ok); font-weight: 700; }

/* ============ FAQ ============ */
.faq { max-width: 720px; margin: 0 auto; }
.faq details {
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 16px 20px; margin-bottom: 12px;
}
.faq summary { font-weight: 600; cursor: pointer; }
.faq details p { margin-top: 10px; color: var(--muted); font-size: 14px; }

/* ============ 表单卡片（激活页/找回页） ============ */
.form-card {
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 32px;
  max-width: 520px; margin: 0 auto;
}
.form-card label { display: block; font-size: 14px; font-weight: 600; margin: 16px 0 6px; }
.form-card input, .form-card select {
  width: 100%; padding: 11px 14px; border: 1px solid var(--border);
  border-radius: 8px; font-size: 15px; background: #fff;
}
.form-card input:focus, .form-card select:focus { outline: 2px solid #c7d2fe; border-color: var(--primary); }
.status { margin-top: 18px; padding: 12px 16px; border-radius: 8px; font-size: 14px; display: none; }
.status.ok { display: block; background: #ecfdf5; color: var(--ok); }
.status.err { display: block; background: #fef2f2; color: var(--err); }
.status.info { display: block; background: #eff6ff; color: #1d4ed8; }
.status .key-display { font-family: monospace; font-size: 18px; letter-spacing: 2px; word-break: break-all; }
.form-card .sub-links { margin-top: 20px; font-size: 13px; color: var(--muted); text-align: center; }

/* ============ 页脚 ============ */
footer { border-top: 1px solid var(--border); padding: 28px 0; margin-top: 40px; }
footer .container { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; color: var(--muted); font-size: 13px; }
footer a { color: var(--muted); margin-left: 16px; }

/* ============ 响应式 ============ */
@media (max-width: 640px) {
  .hero h1 { font-size: 30px; }
  nav .links a { margin-left: 12px; font-size: 13px; }
}