:root {
  --ink: #0b1f3a;
  --cyan: #00c2c7;
  --cyan-dark: #08979c;
  --paper: #f4f7fb;
  --card: #ffffff;
  --line: #d5deea;
  --muted: #5b6b80;
  --danger: #c0392b;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--paper);
  color: var(--ink);
  line-height: 1.75;
  font-size: 16px;
}

.wrap { width: min(1180px, calc(100% - 32px)); margin: 0 auto; }

.topbar {
  background: var(--ink);
  color: #fff;
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 3px solid var(--cyan);
}
.topbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 64px;
  gap: 16px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #fff;
  text-decoration: none;
  font-weight: 700;
  font-size: 18px;
}
.brand svg { flex-shrink: 0; }
nav { display: flex; gap: 6px; }
nav a {
  color: #c9d6e8;
  text-decoration: none;
  padding: 8px 14px;
  border-radius: 4px;
  font-size: 14px;
}
nav a:hover { color: #fff; background: rgba(255,255,255,.08); }
nav a.current { color: var(--ink); background: var(--cyan); font-weight: 700; }

.hero {
  display: grid;
  grid-template-columns: 1.4fr .9fr;
  gap: 36px;
  padding: 48px 0 28px;
  align-items: start;
}
.hero h1 {
  font-size: 32px;
  line-height: 1.35;
  margin-bottom: 16px;
}
.hero .lead { color: var(--muted); margin-bottom: 22px; }
.cta-row { display: flex; flex-wrap: wrap; gap: 10px; }
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  padding: 12px 18px;
  border-radius: 6px;
  font-weight: 700;
  font-size: 15px;
}
.btn-primary { background: var(--cyan); color: var(--ink); }
.btn-primary:hover { background: #17d4d9; }
.btn-ghost { background: #fff; color: var(--ink); border: 1px solid var(--line); }
.btn-ghost:hover { border-color: var(--cyan); }
.hero-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-top: 4px solid var(--cyan);
  padding: 22px;
  box-shadow: 0 10px 28px rgba(11,31,58,.06);
}
.hero-card h2 { font-size: 18px; margin-bottom: 12px; }
.dl-list { list-style: none; }
.dl-list li { margin-bottom: 10px; }
.dl-list a { color: var(--cyan-dark); font-weight: 600; }

.layout {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 28px;
  padding-bottom: 48px;
}
main section {
  background: var(--card);
  border: 1px solid var(--line);
  padding: 26px 28px;
  margin-bottom: 18px;
}
main h2 {
  font-size: 22px;
  margin-bottom: 12px;
  padding-left: 12px;
  border-left: 4px solid var(--cyan);
}
p { margin-bottom: 12px; }
ul, ol { margin: 0 0 12px 22px; }
table {
  width: 100%;
  border-collapse: collapse;
  margin: 12px 0 16px;
  font-size: 14px;
}
th, td { border: 1px solid var(--line); padding: 8px 10px; text-align: left; }
th { background: #e8eef6; }
.aside {
  position: sticky;
  top: 80px;
  background: var(--ink);
  color: #d7e2ef;
  padding: 20px;
  height: fit-content;
}
.aside h2 { color: #fff; border: 0; padding: 0; font-size: 18px; margin-bottom: 10px; }
.aside a { color: var(--cyan); }
.faq dt { font-weight: 700; margin-top: 14px; }
.faq dd { color: var(--muted); margin-left: 0; }

footer {
  background: var(--ink);
  color: #c5d0de;
  padding: 28px 0;
  font-size: 13px;
}
footer strong { color: #fff; }
footer p { margin-bottom: 8px; }
.safe { color: #8de4e6; }

@media (max-width: 900px) {
  .hero, .layout { grid-template-columns: 1fr; }
  .aside { position: static; }
  nav { flex-wrap: wrap; }
}