:root {
  --bg: #05080f;
  --panel: rgba(11, 19, 34, 0.72);
  --line: #16324a;
  --text: #d8ecff;
  --muted: #6b83a0;
  --cyan: #00c8ff;
  --cyan-2: #7de3ff;
  --blue: #2f7bff;
}

* { 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(--bg);
  color: var(--text);
  min-height: 100vh;
  overflow-x: hidden;
}

.bg-grid {
  position: fixed; inset: 0; pointer-events: none;
  background-image:
    linear-gradient(rgba(0, 200, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 200, 255, 0.05) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse at 50% 20%, #000 20%, transparent 75%);
}
.orb {
  position: fixed; border-radius: 50%; filter: blur(80px); pointer-events: none;
}
.orb-a { width: 420px; height: 420px; background: rgba(0, 200, 255, 0.16); top: -80px; right: -40px; }
.orb-b { width: 360px; height: 360px; background: rgba(47, 123, 255, 0.14); bottom: 10%; left: -80px; }

.nav {
  position: sticky; top: 0; z-index: 20;
  display: flex; align-items: center; justify-content: space-between;
  padding: 18px 7vw;
  background: rgba(5, 8, 15, 0.72);
  border-bottom: 1px solid rgba(22, 50, 74, 0.8);
  backdrop-filter: blur(16px);
}
.brand { display: flex; align-items: center; gap: 10px; color: #fff; text-decoration: none; font-weight: 800; letter-spacing: 1px; }
.brand img { width: 36px; height: 36px; border-radius: 8px; }
.nav nav { display: flex; gap: 28px; }
.nav a { color: var(--muted); text-decoration: none; font-size: 14px; }
.nav nav a:hover { color: var(--cyan-2); }

.hero {
  padding: 88px 7vw 40px;
  text-align: center;
}
.kicker {
  color: var(--cyan);
  letter-spacing: 4px;
  font-size: 12px;
  font-weight: 700;
  margin-bottom: 16px;
}
.hero h1 {
  font-size: clamp(36px, 6vw, 68px);
  line-height: 1.15;
  font-weight: 800;
}
.hero h1 em {
  font-style: normal;
  background: linear-gradient(90deg, var(--cyan), var(--blue));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.lead {
  max-width: 680px;
  margin: 22px auto 0;
  color: var(--muted);
  font-size: 18px;
  line-height: 1.7;
}
.hero-actions { margin-top: 32px; display: flex; justify-content: center; gap: 14px; flex-wrap: wrap; }
.hero-logo-wrap {
  position: relative; width: 220px; height: 220px; margin: 56px auto 0;
}
.hero-logo {
  width: 180px; height: 180px; border-radius: 36px;
  position: relative; z-index: 1;
  box-shadow: 0 20px 60px rgba(0, 200, 255, 0.2);
}
.hero-ring {
  position: absolute; inset: -10px;
  border: 1px solid rgba(0, 200, 255, 0.35);
  border-radius: 48px;
  animation: pulse 3.6s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { transform: scale(0.96); opacity: 0.45; }
  50% { transform: scale(1.04); opacity: 1; }
}

.btn {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 148px; height: 46px; padding: 0 22px;
  border-radius: 10px; text-decoration: none; font-weight: 700;
  letter-spacing: 1px;
}
.btn.primary {
  color: #03111c;
  background: linear-gradient(90deg, var(--cyan), var(--blue));
}
.btn.primary:hover { filter: brightness(1.08); }
.btn.ghost {
  color: var(--cyan-2);
  border: 1px solid #1a4a66;
  background: rgba(13, 22, 38, 0.6);
}
.btn.ghost:hover { border-color: var(--cyan); color: #fff; }

.section { padding: 80px 7vw; }
.section-head { margin-bottom: 36px; }
.section-head h2 { font-size: 32px; margin-top: 8px; }
.section-head .sub { color: var(--muted); margin-top: 10px; }

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}
.card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 22px;
  min-height: 180px;
}
.card .tag { color: var(--cyan); font-weight: 800; letter-spacing: 1px; }
.card h3 { margin: 10px 0 8px; }
.card p { color: var(--muted); line-height: 1.65; font-size: 14px; }

.download { background: linear-gradient(180deg, transparent, rgba(0, 200, 255, 0.04), transparent); }
.dl-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
}
.dl-card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 28px;
}
.dl-card.featured { border-color: var(--cyan); box-shadow: 0 0 0 1px rgba(0, 200, 255, 0.2), 0 20px 50px rgba(0, 200, 255, 0.08); }
.dl-type { color: var(--cyan); letter-spacing: 3px; font-size: 12px; font-weight: 700; }
.dl-card h3 { font-size: 28px; margin: 8px 0 12px; }
.dl-card p, .dl-card li { color: var(--muted); line-height: 1.7; }
.dl-card ul { margin: 16px 0 24px 18px; }
.dl-card .btn { width: 100%; }

.steps { list-style: none; display: grid; gap: 14px; }
.steps li {
  display: grid; gap: 4px;
  padding: 18px 20px;
  border-left: 3px solid var(--cyan);
  background: var(--panel);
  border-radius: 0 12px 12px 0;
}
.steps strong { font-size: 18px; }
.steps span { color: var(--muted); }

.foot {
  display: flex; align-items: center; gap: 16px;
  padding: 28px 7vw 40px;
  border-top: 1px solid var(--line);
  color: var(--muted);
}
.foot img { width: 40px; height: 40px; border-radius: 8px; }
.foot strong { color: #fff; display: block; margin-bottom: 4px; }
.foot .copy { margin-left: auto; }

.article {
  max-width: 780px; margin: 0 auto; padding: 48px 7vw 80px;
}
.article h1 { font-size: 36px; margin: 12px 0 24px; }
.article h2 { margin: 36px 0 12px; color: var(--cyan-2); }
.article p, .article li { color: #b8d4ee; line-height: 1.9; margin-bottom: 14px; }
.article ul { padding-left: 20px; }
.article blockquote {
  border-left: 3px solid var(--cyan);
  padding: 8px 16px;
  color: var(--muted);
  margin-bottom: 20px;
}

@media (max-width: 720px) {
  .nav nav { display: none; }
  .foot { flex-direction: column; align-items: flex-start; }
  .foot .copy { margin-left: 0; }
}