:root {
  --bg: #EEF2F7;
  --navy: #1B2A4A;
  --accent: #3D8B6E;
  --ink: #1C2433;
  --muted: #4A5568;
  --card: #FFFFFF;
  --line: #D3DCE8;
}

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

html { scroll-behavior: auto; }

body {
  font-family: Palatino, "Palatino Linotype", "Microsoft YaHei", serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.78;
  font-size: 17px;
}

a { color: var(--accent); text-decoration: none; }

svg { display: block; }

.wrap {
  width: min(1140px, calc(100% - 36px));
  margin: 0 auto;
}

/* 顶栏：logo 左、导航右 */
.site-header {
  background: var(--navy);
  color: #F4F7FB;
}

.site-header .bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 68px;
  gap: 20px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #F4F7FB;
  font-size: 18px;
}

.brand svg { width: 30px; height: 30px; }

.nav { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 12px 16px; }

.nav a {
  color: #C9D4E6;
  font-size: 13px;
  padding-bottom: 3px;
  border-bottom: 1px solid transparent;
}

.nav a:hover,
.nav a:focus {
  color: #fff;
  border-bottom-color: var(--accent);
}

.hero { padding: 40px 0 12px; }

.hero h1 {
  font-size: 32px;
  color: var(--navy);
  margin-bottom: 14px;
}

.hero p { color: var(--muted); max-width: 44em; margin-bottom: 8px; }

.btn {
  display: inline-block;
  margin-top: 10px;
  background: var(--navy);
  color: #fff;
  padding: 8px 16px;
  font-size: 14px;
}

.btn:hover { background: #24365E; }

/* 设备轨 */
.track {
  display: grid;
  grid-template-columns: 1fr 40px 1fr 40px 1fr;
  align-items: stretch;
  gap: 0;
  margin: 28px 0 8px;
}

.station {
  background: var(--card);
  border-left: 5px solid var(--accent);
  padding: 16px 14px;
}

.station svg { width: 36px; height: 36px; margin-bottom: 8px; color: var(--accent); }

.station h3 { font-size: 16px; margin-bottom: 6px; }

.station p { font-size: 13px; color: var(--muted); }

.rail {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
}

.rail span {
  width: 100%;
  height: 2px;
  background: repeating-linear-gradient(90deg, var(--accent), var(--accent) 6px, transparent 6px, transparent 10px);
}

section { padding: 38px 0; }

section h2 {
  font-size: 25px;
  color: var(--navy);
  margin-bottom: 18px;
  letter-spacing: 0.02em;
}

/* 左绿条白卡 */
.stripe-card {
  background: var(--card);
  border-left: 5px solid var(--accent);
  padding: 18px 16px;
}

.stripe-card h3 { font-size: 17px; margin-bottom: 6px; color: var(--navy); }

.stripe-card p { font-size: 14px; color: var(--muted); }

.stripe-card svg { width: 26px; height: 26px; margin-bottom: 8px; color: var(--accent); }

.cols-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}

/* 关掉 vs 退出 */
.vs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.vs-box {
  background: var(--card);
  padding: 22px;
  border-left: 5px solid var(--accent);
}

.vs-box.exit { border-left-color: #8B4A4A; }

.vs-box h3 { margin-bottom: 8px; }

.vs-box ul { padding-left: 1.2em; color: var(--muted); font-size: 15px; }

.vs-box li { margin: 7px 0; }

/* 编号步骤 */
.num-steps { counter-reset: n; }

.num-steps li {
  list-style: none;
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 12px;
  margin-bottom: 16px;
  background: var(--card);
  padding: 14px;
  border-left: 5px solid var(--accent);
}

.num-steps li::before {
  counter-increment: n;
  content: counter(n);
  width: 36px;
  height: 36px;
  background: var(--navy);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
}

.num-steps h3 { font-size: 17px; margin-bottom: 4px; }

.num-steps p { font-size: 14px; color: var(--muted); }

table {
  width: 100%;
  border-collapse: collapse;
  background: var(--card);
  font-size: 15px;
}

th, td {
  border: 1px solid var(--line);
  padding: 11px 12px;
  text-align: left;
  vertical-align: top;
}

th { background: var(--navy); color: #fff; }

/* 3 列场景 */
.scenes-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.edge {
  background: #E4EAF2;
  padding: 16px 18px;
  font-size: 15px;
  color: var(--muted);
}

.edge p + p { margin-top: 8px; }

/* FAQ ol + h3 */
.faq-ol { list-style: none; }

.faq-ol > li {
  background: var(--card);
  border-left: 5px solid var(--accent);
  padding: 16px 18px;
  margin-bottom: 10px;
}

.faq-ol h3 { font-size: 17px; color: var(--navy); margin-bottom: 6px; }

.faq-ol p { font-size: 15px; color: var(--muted); }

.site-footer {
  background: var(--navy);
  color: #C9D4E6;
  padding: 30px 0 38px;
  font-size: 13px;
}

.site-footer p { margin: 8px 0; }

@media (max-width: 900px) {
  .site-header .bar { flex-direction: column; align-items: flex-start; padding: 12px 0; }
  .nav { justify-content: flex-start; }
  .track { grid-template-columns: 1fr; }
  .rail { height: 20px; }
  .rail span { width: 2px; height: 100%; background: var(--accent); }
  .cols-4,
  .vs,
  .scenes-3 { grid-template-columns: 1fr; }
}