/* Set 2 — www: sticky left rail, teal workspace */
:root {
  --bg: #e6f4f1;
  --panel: #ffffff;
  --ink: #16302f;
  --dim: #3f5d5b;
  --teal: #0f3d3e;
  --accent: #1a8a7a;
  --line: #c5ddd9;
}
* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  font-family: "Trebuchet MS", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.7;
  font-size: 15.5px;
}
a { color: var(--accent); }
.shell {
  display: grid;
  grid-template-columns: 240px 1fr;
  min-height: 100vh;
}
.rail {
  background: var(--teal);
  color: #e8f6f3;
  padding: 28px 20px 40px;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow: auto;
}
.rail .brand {
  display: block;
  color: #fff;
  text-decoration: none;
  font-size: 26px;
  font-weight: 800;
  letter-spacing: 0.04em;
  margin-bottom: 28px;
}
.rail nav { display: flex; flex-direction: column; gap: 6px; }
.rail nav a {
  color: #cfe8e3;
  text-decoration: none;
  padding: 10px 12px;
  border-left: 3px solid transparent;
}
.rail nav a.is-current {
  background: rgba(255,255,255,0.08);
  border-left-color: #7ee0cf;
  color: #fff;
}
.rail .mini-cta {
  display: block;
  margin-top: 28px;
  background: #7ee0cf;
  color: #0b2c2d;
  text-align: center;
  text-decoration: none;
  padding: 12px 10px;
  font-weight: 700;
}
.canvas { padding: 36px 48px 64px; }
.kicker {
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 8px;
}
h1 { font-size: clamp(26px, 3vw, 34px); line-height: 1.35; margin: 0 0 14px; }
.lead { color: var(--dim); margin: 0 0 22px; max-width: 70ch; }
.btn {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  text-decoration: none;
  padding: 12px 22px;
  font-weight: 700;
}
.btn-line {
  display: inline-block;
  margin-left: 8px;
  border: 1px solid var(--accent);
  color: var(--accent);
  text-decoration: none;
  padding: 11px 20px;
}
.two {
  display: grid;
  grid-template-columns: 1.4fr 0.8fr;
  gap: 20px;
  margin: 28px 0;
}
.box {
  background: var(--panel);
  border: 1px solid var(--line);
  padding: 18px 20px;
}
h2 {
  font-size: 20px;
  margin: 28px 0 10px;
  color: var(--teal);
}
.icon { width: 16px; height: 16px; vertical-align: -2px; fill: currentColor; }
.faq-item { background: var(--panel); border: 1px solid var(--line); padding: 14px 16px; margin: 10px 0; }
.faq-item h3 { margin: 0 0 6px; font-size: 16px; }
.site-footer {
  margin-top: 40px;
  padding-top: 20px;
  border-top: 2px solid var(--teal);
  font-size: 13px;
  color: var(--dim);
}
.site-footer nav { display: flex; gap: 14px; margin: 10px 0; }
.req-table { width: 100%; border-collapse: collapse; }
.req-table th, .req-table td { border: 1px solid var(--line); padding: 8px 10px; background: #fff; }
.req-table th { background: #d8efe9; }
@media (max-width: 900px) {
  .shell { grid-template-columns: 1fr; }
  .rail { position: relative; height: auto; }
  .rail nav { flex-direction: row; flex-wrap: wrap; }
  .two { grid-template-columns: 1fr; }
  .canvas { padding: 24px 18px 48px; }
}