:root {
  --sea: #102733;
  --sea-2: #1a4652;
  --foam: #e7eef0;
  --card: #ffffff;
  --ink: #16232c;
  --muted: #4d616b;
  --teal: #0f9e96;
  --line: #d5e1e4;
}
* { box-sizing: border-box; }
html { scroll-behavior: auto; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--foam);
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.75;
  font-size: 17px;
}
a { color: #0b6e68; }
a:focus-visible, button:focus-visible { outline: 3px solid #f4b942; outline-offset: 2px; }
.rail {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: 252px;
  background: var(--sea);
  color: #d5e6ea;
  display: flex;
  flex-direction: column;
  z-index: 3;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 22px 18px 12px;
  color: #fff;
  text-decoration: none;
  font-size: 24px;
  font-weight: 700;
  letter-spacing: 0.06em;
}
.brand svg { flex: 0 0 auto; }
.side-nav { display: flex; flex-direction: column; padding: 8px 12px 0; }
.side-nav a {
  color: #d5e6ea;
  text-decoration: none;
  padding: 12px 12px;
  border-left: 4px solid transparent;
}
.side-nav a.is-current { color: #fff; border-left-color: var(--teal); background: rgba(255,255,255,0.05); }
.side-cta { margin: 20px 16px; }
.side-cta a, .btn {
  display: inline-block;
  background: var(--teal);
  color: #042421;
  text-decoration: none;
  font-weight: 700;
  padding: 12px 16px;
  border-radius: 0;
}
.side-cta a { display: block; text-align: center; }
.btn.ghost { background: transparent; color: #fff; border: 1px solid rgba(255,255,255,0.7); margin-left: 10px; }
.rail-note { margin-top: auto; padding: 16px 18px 22px; font-size: 13px; color: #9fb6bd; }
.canvas { margin-left: 252px; }
.stage {
  background: linear-gradient(145deg, var(--sea) 0%, var(--sea-2) 78%);
  color: #f3fbfb;
  padding: 42px 48px 36px;
}
.stage h1 { margin: 0 0 12px; font-size: 34px; line-height: 1.28; letter-spacing: 0; max-width: 18em; }
.lede { margin: 0 0 16px; max-width: 42em; color: #e5f4f4; }
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 0 0 18px; padding: 0; list-style: none; }
.chips li { border: 1px solid rgba(255,255,255,0.35); padding: 6px 10px; font-size: 14px; }
.sheet { padding: 8px 8px 36px; }
.panel {
  background: var(--card);
  margin: 16px;
  padding: 28px 32px 30px;
  border-top: 6px solid var(--sea);
}
.panel h2 { margin: 0 0 12px; font-size: 26px; line-height: 1.35; }
.panel p { margin: 0 0 12px; }
.scene-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-top: 8px; }
.scene-grid article { background: #f4f8f8; padding: 14px 16px; border-left: 4px solid var(--teal); }
.scene-grid h3 { margin: 0 0 6px; font-size: 18px; }
.plain { width: 100%; border-collapse: collapse; margin: 12px 0 4px; font-size: 15px; }
.plain th, .plain td { border-bottom: 1px solid var(--line); text-align: left; padding: 8px 10px; vertical-align: top; }
.plain th { background: #f3f7f7; font-weight: 650; }
.quotes { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.quotes blockquote { margin: 0; background: #f6fbfb; padding: 14px 16px; border-top: 3px solid var(--teal); }
.quotes p { margin: 0; }
.faq dt { font-weight: 700; margin-top: 16px; }
.faq dd { margin: 6px 0 0; color: var(--ink); }
.site-foot { margin: 0 16px 28px; padding: 16px 8px 0; color: var(--muted); font-size: 13px; line-height: 1.7; }
.site-foot p { margin: 0 0 8px; }
@media (max-width: 900px) {
  .rail { position: static; width: auto; }
  .canvas { margin-left: 0; }
  .brand { padding: 12px 16px 4px; }
  .side-nav a { padding: 8px 12px; }
  .side-cta { margin: 8px 16px 10px; }
  .rail-note { display: none; }
  .stage, .panel { padding: 18px 16px; }
  .stage h1 { font-size: 28px; }
  .panel { margin: 12px; }
  .scene-grid, .quotes { grid-template-columns: 1fr; }
  .btn.ghost { margin-left: 0; margin-top: 8px; }
}