:root {
  --bg: #0b0f16;
  --surface: #141a24;
  --surface2: #1a2233;
  --border: #263246;
  --fg: #dfe7f2;
  --bright: #f7f9fc;
  --muted: #99a6b8;
  --blue: #4f83ff;
  --green: #32c975;
  --max: 920px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; background: var(--bg); color: var(--fg); font: 16px/1.75 -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif; }
a { color: #78a4ff; }
a:hover { color: #a9c5ff; }
header { border-bottom: 1px solid var(--border); background: rgba(11,15,22,.94); position: sticky; top: 0; z-index: 5; }
.nav { max-width: 1120px; margin: auto; min-height: 60px; padding: 10px 22px; display: flex; align-items: center; justify-content: space-between; gap: 18px; }
.brand { color: var(--bright); text-decoration: none; font-size: 1.22rem; font-weight: 750; }
.links { display: flex; flex-wrap: wrap; gap: 18px; font-size: .9rem; }
.links a { color: var(--muted); text-decoration: none; }
main { max-width: var(--max); margin: auto; padding: 60px 22px 90px; }
.eyebrow { color: var(--blue); font-weight: 700; letter-spacing: .08em; text-transform: uppercase; font-size: .78rem; }
h1 { color: var(--bright); font-size: clamp(2rem, 5vw, 3.25rem); line-height: 1.18; letter-spacing: -.035em; margin: 12px 0 20px; }
h2 { color: var(--bright); margin: 52px 0 14px; line-height: 1.3; font-size: 1.65rem; }
h3 { color: var(--bright); margin: 30px 0 8px; }
.lead { font-size: 1.16rem; color: var(--muted); max-width: 780px; }
.meta { color: var(--muted); font-size: .88rem; margin: 18px 0 30px; }
.callout, .fact, .faq { background: var(--surface); border: 1px solid var(--border); border-radius: 12px; padding: 20px 22px; margin: 18px 0; }
.callout { border-left: 4px solid var(--blue); }
.grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.fact h3, .faq h3 { margin-top: 0; }
.toc { background: var(--surface); border: 1px solid var(--border); border-radius: 12px; padding: 20px 28px; margin: 34px 0; }
.toc a { text-decoration: none; }
table { width: 100%; border-collapse: collapse; margin: 22px 0; display: block; overflow-x: auto; }
th, td { border: 1px solid var(--border); padding: 12px 14px; text-align: left; vertical-align: top; min-width: 140px; }
th { color: var(--bright); background: var(--surface2); }
code { background: var(--surface2); border: 1px solid var(--border); border-radius: 5px; padding: 1px 5px; }
.yes { color: var(--green); font-weight: 700; }
.cta { text-align: center; margin-top: 56px; padding: 34px; background: linear-gradient(135deg, #16223a, #111925); border: 1px solid var(--border); border-radius: 14px; }
.button { display: inline-block; padding: 11px 22px; margin: 6px; background: #2563eb; color: white; text-decoration: none; border-radius: 8px; font-weight: 700; }
.button.secondary { background: transparent; border: 1px solid #60708a; }
footer { border-top: 1px solid var(--border); color: var(--muted); text-align: center; padding: 30px 20px; font-size: .85rem; }
@media (max-width: 680px) { .grid { grid-template-columns: 1fr; } .brand { font-size: 1.05rem; white-space: nowrap; } .links { gap: 8px; justify-content: flex-end; font-size: .82rem; } main { padding-top: 38px; } }