/* ============================================================
   全站样式（无 CDN，纯手写）
   设计基调：现代极简 / 卡片布局 / 蓝金渐变主按钮 / 克制动效
   ============================================================ */

:root {
  --bg: #f6f7f9;
  --surface: #ffffff;
  --surface-muted: #f0f2f5;
  --text: #1f2329;
  --text-2: #55606e;
  --text-3: #8a919f;
  --border: #e5e7eb;
  --blue: #3b82f6;
  --blue-deep: #1d4ed8;
  --gold: #f59e0b;
  --gold-deep: #b45309;
  --grad-main: linear-gradient(135deg, #3b82f6 0%, #1d4ed8 100%);
  --grad-warm: linear-gradient(135deg, #fbbf24 0%, #f59e0b 55%, #d97706 100%);
  --shadow-card: 0 1px 4px rgba(15, 23, 42, .06);
  --shadow-pop: 0 8px 24px rgba(29, 78, 216, .18);
  --radius: 12px;
  --radius-lg: 16px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

.wrap { max-width: 860px; margin: 0 auto; padding: 0 16px; }

/* ---------- 顶部导航 ---------- */
.nav {
  position: sticky; top: 0; z-index: 10;
  background: rgba(255, 255, 255, .92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.nav .wrap { display: flex; align-items: center; justify-content: space-between; height: 56px; }
.brand { display: flex; align-items: center; gap: 8px; font-weight: 700; font-size: 16px; color: var(--text); text-decoration: none; }
.brand svg { width: 22px; height: 22px; }
.nav-links { display: flex; gap: 18px; }
.nav-links a { color: var(--text-2); text-decoration: none; font-size: 14px; }
.nav-links a:hover { color: var(--blue-deep); }

/* ---------- Hero ---------- */
.hero { text-align: center; padding: 64px 0 48px; }
.hero .badge {
  display: inline-block; padding: 4px 14px; border-radius: 999px;
  background: var(--surface-muted); color: var(--text-2);
  font-size: 13px; margin-bottom: 18px; border: 1px solid var(--border);
}
.hero h1 { font-size: 32px; line-height: 1.35; margin: 0 0 14px; letter-spacing: .5px; }
.hero h1 .hl { background: var(--grad-warm); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero p.sub { color: var(--text-2); font-size: 16px; max-width: 560px; margin: 0 auto 28px; }

/* ---------- 按钮（金蓝渐变 + 悬停缩放） ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 13px 34px; border-radius: 999px; border: none; cursor: pointer;
  font-size: 16px; font-weight: 600; color: #fff; text-decoration: none;
  background: var(--grad-main); box-shadow: var(--shadow-pop);
  transition: transform .12s ease, box-shadow .12s ease, opacity .12s ease;
}
.btn:hover { transform: translateY(-2px) scale(1.03); box-shadow: 0 12px 28px rgba(29, 78, 216, .26); }
.btn:active { transform: scale(.98); }
.btn.gold { background: var(--grad-warm); color: #4a2b00; box-shadow: 0 8px 24px rgba(217, 119, 6, .22); }
.btn.ghost { background: var(--surface); color: var(--text); border: 1px solid var(--border); box-shadow: var(--shadow-card); }
.btn.block { width: 100%; }
.btn svg { width: 18px; height: 18px; }

/* ---------- 卡片与栅格 ---------- */
.section { padding: 36px 0; }
.section > h2 { font-size: 22px; text-align: center; margin: 0 0 8px; }
.section > p.lead { text-align: center; color: var(--text-3); font-size: 14px; margin: 0 0 28px; }
.grid { display: grid; gap: 14px; }
.grid.cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid.cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid.cols-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 720px) {
  .grid.cols-3, .grid.cols-4 { grid-template-columns: repeat(2, 1fr); }
  .hero h1 { font-size: 25px; }
}
@media (max-width: 460px) {
  .grid.cols-2, .grid.cols-3, .grid.cols-4 { grid-template-columns: 1fr; }
  .nav-links { display: none; }
}

.card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 22px 18px; box-shadow: var(--shadow-card);
  transition: transform .12s ease, box-shadow .12s ease;
}
.card:hover { transform: translateY(-3px); box-shadow: 0 10px 24px rgba(15, 23, 42, .10); }
.card .icon {
  width: 42px; height: 42px; border-radius: 12px; display: flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, #eff6ff, #dbeafe); margin-bottom: 12px;
}
.card .icon svg { width: 22px; height: 22px; stroke: var(--blue-deep); }
.card.warm .icon { background: linear-gradient(135deg, #fffbeb, #fef3c7); }
.card.warm .icon svg { stroke: var(--gold-deep); }
.card h3 { margin: 0 0 6px; font-size: 16px; }
.card p { margin: 0; color: var(--text-2); font-size: 14px; }

/* ---------- 步骤 ---------- */
.steps { counter-reset: step; display: grid; gap: 14px; grid-template-columns: repeat(3, 1fr); }
@media (max-width: 720px) { .steps { grid-template-columns: 1fr; } }
.step { position: relative; background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 22px 18px 18px 18px; box-shadow: var(--shadow-card); }
.step::before {
  counter-increment: step; content: counter(step);
  position: absolute; top: -14px; left: 18px;
  width: 28px; height: 28px; border-radius: 50%;
  background: var(--grad-main); color: #fff; font-weight: 700; font-size: 14px;
  display: flex; align-items: center; justify-content: center; box-shadow: var(--shadow-pop);
}
.step h3 { margin: 4px 0 6px; font-size: 15px; }
.step p { margin: 0; font-size: 13.5px; color: var(--text-2); }

/* ---------- 价格表 ---------- */
.price-card { text-align: center; position: relative; }
.price-card .tag {
  position: absolute; top: -12px; right: 14px; padding: 3px 12px; border-radius: 999px;
  background: var(--grad-warm); color: #4a2b00; font-size: 12px; font-weight: 700;
}
.price-card .price { font-size: 30px; font-weight: 800; margin: 10px 0 2px; }
.price-card .price small { font-size: 14px; font-weight: 400; color: var(--text-3); }
.price-card ul { list-style: none; padding: 0; margin: 14px 0 18px; text-align: left; }
.price-card li { padding: 6px 0 6px 24px; position: relative; color: var(--text-2); font-size: 14px; border-bottom: 1px dashed var(--border); }
.price-card li:last-child { border-bottom: none; }
.price-card li::before {
  content: ""; position: absolute; left: 2px; top: 13px;
  width: 12px; height: 12px; border-radius: 50%;
  background: var(--grad-main);
  -webkit-mask: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="black" stroke-width="3"><path d="M20 6 9 17l-5-5"/></svg>') center/contain no-repeat;
  mask: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="black" stroke-width="3"><path d="M20 6 9 17l-5-5"/></svg>') center/contain no-repeat;
  background: #1d4ed8;
}

/* ---------- 引导页（onboarding） ---------- */
.ob-hero { text-align: center; padding: 36px 0 8px; }
.ob-num { color: var(--text-3); font-size: 13px; letter-spacing: 2px; }
.notice {
  background: #fffbeb; border: 1px solid #fde68a; color: #92400e;
  border-radius: var(--radius); padding: 14px 16px; font-size: 14px; margin: 16px 0;
}
.notice.blue { background: #eff6ff; border-color: #bfdbfe; color: #1e40af; }
.notice.red { background: #fef2f2; border-color: #fecaca; color: #991b1b; }

/* ---------- 页脚 ---------- */
footer { border-top: 1px solid var(--border); margin-top: 40px; padding: 26px 0 40px; color: var(--text-3); font-size: 13px; }
footer .wrap { display: flex; flex-direction: column; gap: 6px; text-align: center; }
footer a { color: var(--text-2); text-decoration: none; margin: 0 8px; }
footer a:hover { color: var(--blue-deep); }

/* ---------- 协议文档 ---------- */
.doc { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: 30px 26px; box-shadow: var(--shadow-card); }
.doc h1 { font-size: 22px; margin: 0 0 4px; }
.doc .meta { color: var(--text-3); font-size: 13px; margin-bottom: 22px; }
.doc h2 { font-size: 17px; margin: 26px 0 8px; }
.doc p, .doc li { font-size: 14.5px; color: var(--text-2); }
.doc strong { color: var(--text); }