:root {
  --bg: #071113;
  --ink: #f0f8f8;
  --muted: #a8babb;
  --line: rgba(221, 246, 246, 0.17);
  --panel: rgba(12, 24, 27, 0.9);
  --panel-2: rgba(20, 36, 41, 0.92);
  --aqua: #48d8c8;
  --gold: #f1c85a;
  --coral: #ff765e;
  --green: #74c66b;
  --radius: 8px;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.32);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--bg);
  font-family: Inter, "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  letter-spacing: 0;
}

a {
  color: inherit;
}

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  gap: 18px;
  min-height: 66px;
  padding: 0 28px;
  border-bottom: 1px solid var(--line);
  background: rgba(7, 17, 19, 0.86);
  backdrop-filter: blur(16px);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  min-width: 220px;
  color: var(--ink);
  text-decoration: none;
  font-weight: 850;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border: 1px solid rgba(72, 216, 200, 0.45);
  border-radius: 50%;
  color: var(--aqua);
  background: rgba(72, 216, 200, 0.1);
}

.nav {
  display: flex;
  gap: 6px;
  margin-left: auto;
}

.nav a {
  padding: 10px 11px;
  border-radius: 7px;
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
}

.nav a:hover {
  color: var(--ink);
  background: rgba(255, 255, 255, 0.08);
}

.wrap {
  width: min(1180px, calc(100% - 44px));
  margin: 0 auto;
}

.hero {
  min-height: 460px;
  display: grid;
  align-items: end;
  padding: 72px 0 34px;
  background:
    linear-gradient(180deg, rgba(7, 17, 19, 0.18), var(--bg)),
    var(--hero-image) center / cover no-repeat;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 0 11px;
  border: 1px solid rgba(72, 216, 200, 0.44);
  border-radius: 999px;
  color: #c9fff7;
  background: rgba(7, 17, 19, 0.58);
  font-size: 13px;
  font-weight: 800;
}

h1 {
  max-width: 880px;
  margin: 18px 0 0;
  font-size: clamp(40px, 6vw, 76px);
  line-height: 0.98;
  letter-spacing: 0;
}

.hero p {
  max-width: 760px;
  margin: 18px 0 0;
  color: #d9eeee;
  font-size: 18px;
  line-height: 1.75;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 18px;
}

.tag {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 0 9px;
  border: 1px solid rgba(240, 248, 248, 0.18);
  border-radius: 999px;
  color: #ecffff;
  background: rgba(7, 17, 19, 0.42);
  font-size: 12px;
  white-space: nowrap;
  text-decoration: none;
}

.shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 310px;
  gap: 22px;
  padding: 28px 0 54px;
}

.section,
.rail-card,
.guide-card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  box-shadow: var(--shadow);
  backdrop-filter: blur(12px);
}

.content {
  display: grid;
  gap: 20px;
}

.section {
  padding: 26px;
  scroll-margin-top: 86px;
}

.section h2 {
  margin: 0 0 16px;
  font-size: 28px;
}

.section h3 {
  margin: 0 0 8px;
  font-size: 19px;
}

.section p,
.section li {
  color: var(--muted);
  line-height: 1.74;
}

.grid-2,
.grid-3 {
  display: grid;
  gap: 14px;
}

.grid-2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.guide-card {
  padding: 18px;
  background: var(--panel-2);
  box-shadow: none;
}

.steps {
  counter-reset: step;
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.steps li {
  counter-increment: step;
  display: grid;
  grid-template-columns: 38px 1fr;
  gap: 14px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 7px;
  background: rgba(255, 255, 255, 0.045);
}

.steps li::before {
  content: counter(step);
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  color: #051212;
  background: var(--aqua);
  font-weight: 850;
}

.steps strong {
  display: block;
  margin-bottom: 5px;
  color: var(--ink);
}

.tool-table {
  width: 100%;
  border-collapse: collapse;
  overflow: hidden;
  border-radius: 7px;
  font-size: 14px;
}

.tool-table th,
.tool-table td {
  padding: 13px 12px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

.tool-table th {
  color: #cff6f2;
  background: rgba(72, 216, 200, 0.1);
}

.tool-table td {
  color: var(--muted);
}

.note {
  border-left: 3px solid var(--coral);
  padding: 12px 14px;
  border-radius: 0 7px 7px 0;
  background: rgba(255, 118, 94, 0.1);
  color: #ffd0c8;
}

.right-rail {
  display: grid;
  align-content: start;
  gap: 16px;
}

.rail-card {
  padding: 18px;
}

.rail-card h2 {
  margin: 0 0 12px;
  font-size: 15px;
  color: var(--muted);
  text-transform: uppercase;
}

.stats {
  display: grid;
  gap: 10px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.stats li {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  color: var(--muted);
  font-size: 14px;
}

.stats strong {
  color: var(--ink);
  text-align: right;
}

.source-list {
  display: grid;
  gap: 9px;
  margin: 0;
  padding-left: 18px;
}

.source-list a {
  color: #a9fff3;
}

.footer {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding: 16px 0 44px;
  color: var(--muted);
  font-size: 13px;
}

.footer a {
  color: #cffff8;
  text-decoration: none;
}

@media (max-width: 960px) {
  .shell,
  .grid-2,
  .grid-3 {
    grid-template-columns: 1fr;
  }

  .right-rail {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 720px) {
  .topbar {
    padding: 12px 16px;
  }

  .nav {
    display: none;
  }

  .wrap {
    width: min(100% - 28px, 680px);
  }

  .hero {
    min-height: 420px;
    padding-top: 52px;
  }

  .section {
    padding: 20px;
  }

  .right-rail,
  .footer {
    grid-template-columns: 1fr;
    display: grid;
  }

  .tool-table {
    display: block;
    overflow-x: auto;
  }
}