:root {
  --bg: #0a0e14;
  --bg2: #0d1220;
  --panel: #101624;
  --panel2: #131a2b;
  --line: rgba(148, 163, 184, 0.14);
  --line2: rgba(148, 163, 184, 0.28);
  --fg: #dbe4f0;
  --dim: #8b98ab;
  --faint: #5b6779;
  --cyan: #22d3ee;
  --cyan-dim: rgba(34, 211, 238, 0.12);
  --amber: #fbbf24;
  --green: #34d399;
  --mono: "JetBrains Mono", "SFMono-Regular", Consolas, monospace;
  --sans: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  background:
    linear-gradient(rgba(34, 211, 238, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(34, 211, 238, 0.025) 1px, transparent 1px);
  background-size: 44px 44px;
  pointer-events: none;
  z-index: 0;
}

.wrap { max-width: 1080px; margin: 0 auto; padding: 0 24px; position: relative; z-index: 1; }

.mono { font-family: var(--mono); }

/* ---------- nav ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(10, 14, 20, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  display: flex;
  align-items: center;
  gap: 28px;
  height: 60px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--fg);
  margin-right: auto;
}
.brand-mark {
  width: 28px;
  height: 28px;
  border-radius: 7px;
  background: linear-gradient(135deg, #0e7490, #164e63);
  display: grid;
  place-items: center;
  font-family: var(--mono);
  font-weight: 700;
  font-size: 13px;
  color: #a5f3fc;
}
.brand-name { font-family: var(--mono); font-weight: 700; font-size: 15px; letter-spacing: 0.5px; }
.brand-sub { font-family: var(--mono); font-size: 9px; letter-spacing: 2.5px; color: var(--dim); display: block; margin-top: -3px; }
.nav a.link {
  font-family: var(--mono);
  font-size: 12.5px;
  letter-spacing: 0.5px;
  color: var(--dim);
  text-decoration: none;
  transition: color 0.2s;
}
.nav a.link:hover { color: var(--cyan); }
.nav .cta {
  font-family: var(--mono);
  font-size: 12.5px;
  color: #06212a;
  background: var(--cyan);
  padding: 7px 16px;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 700;
  transition: filter 0.2s;
}
.nav .cta:hover { filter: brightness(1.12); }

/* ---------- hero ---------- */
.hero { padding: 88px 0 72px; position: relative; }
.hero::after {
  content: "";
  position: absolute;
  top: -120px;
  right: -180px;
  width: 560px;
  height: 560px;
  background: radial-gradient(circle, rgba(34, 211, 238, 0.09), transparent 65%);
  pointer-events: none;
}
.hero-grid { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 56px; align-items: center; }
.tagline {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 3px;
  color: var(--cyan);
  border: 1px solid rgba(34, 211, 238, 0.35);
  background: var(--cyan-dim);
  display: inline-block;
  padding: 5px 14px;
  border-radius: 999px;
  margin-bottom: 26px;
}
h1 {
  font-size: clamp(30px, 4.6vw, 46px);
  line-height: 1.25;
  font-weight: 700;
  letter-spacing: 0.5px;
}
h1 .hl { color: var(--cyan); }
.hero p.lead { color: var(--dim); margin: 22px 0 34px; max-width: 460px; font-size: 16px; }
.btn-row { display: flex; gap: 14px; flex-wrap: wrap; }
.btn {
  font-family: var(--mono);
  font-size: 13.5px;
  font-weight: 700;
  text-decoration: none;
  padding: 12px 26px;
  border-radius: 8px;
  transition: transform 0.15s, filter 0.2s;
}
.btn:hover { transform: translateY(-1px); filter: brightness(1.1); }
.btn-solid { background: var(--cyan); color: #06212a; }
.btn-ghost { color: var(--fg); border: 1px solid var(--line2); background: var(--panel); }

/* terminal */
.term {
  background: #0b101c;
  border: 1px solid var(--line2);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 30px 80px rgba(0, 0, 0, 0.5);
  font-family: var(--mono);
  font-size: 12.5px;
}
.term-bar {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 14px;
  background: var(--panel2);
  border-bottom: 1px solid var(--line);
}
.term-bar i { width: 10px; height: 10px; border-radius: 50%; display: block; }
.term-bar i:nth-child(1) { background: #f87171; }
.term-bar i:nth-child(2) { background: #fbbf24; }
.term-bar i:nth-child(3) { background: #34d399; }
.term-title { margin-left: 10px; color: var(--faint); font-size: 10.5px; letter-spacing: 1px; }
.term-body { padding: 18px 20px 22px; line-height: 2.05; overflow-x: auto; }
.tl { display: block; white-space: nowrap; opacity: 0; animation: tin 0.01s forwards; }
.tl .p { color: var(--green); }
.tl .c { color: var(--fg); }
.tl .k { color: var(--cyan); }
.tl .d { color: var(--faint); }
.tl .ok { color: var(--green); }
.tl .am { color: var(--amber); }
@keyframes tin { to { opacity: 1; } }
.tl:nth-child(1) { animation-delay: 0.3s; }
.tl:nth-child(2) { animation-delay: 0.9s; }
.tl:nth-child(3) { animation-delay: 1.5s; }
.tl:nth-child(4) { animation-delay: 2.0s; }
.tl:nth-child(5) { animation-delay: 2.5s; }
.tl:nth-child(6) { animation-delay: 3.0s; }
.tl:nth-child(7) { animation-delay: 3.6s; }
.cursor {
  display: inline-block;
  width: 8px;
  height: 15px;
  background: var(--cyan);
  vertical-align: -2px;
  animation: blink 1s steps(1) infinite;
}
@keyframes blink { 50% { opacity: 0; } }

/* ---------- sections ---------- */
section { padding: 76px 0; border-top: 1px solid var(--line); }
.sec-tag {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 3px;
  color: var(--cyan);
  margin-bottom: 14px;
}
h2 { font-size: 28px; font-weight: 700; margin-bottom: 12px; }
.sec-desc { color: var(--dim); max-width: 560px; margin-bottom: 44px; }

.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 26px 24px;
  transition: border-color 0.25s, transform 0.25s;
}
.card:hover { border-color: rgba(34, 211, 238, 0.45); transform: translateY(-3px); }
.card .ic {
  width: 38px;
  height: 38px;
  border-radius: 9px;
  background: var(--cyan-dim);
  border: 1px solid rgba(34, 211, 238, 0.3);
  display: grid;
  place-items: center;
  margin-bottom: 18px;
  color: var(--cyan);
}
.card h3 { font-size: 16px; margin-bottom: 8px; }
.card p { color: var(--dim); font-size: 13.5px; }

/* stats strip */
.stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); border-radius: 12px; overflow: hidden; }
.stat { background: var(--panel); padding: 26px 22px; }
.stat b { font-family: var(--mono); font-size: 26px; color: var(--cyan); display: block; }
.stat span { color: var(--dim); font-size: 12.5px; }

/* ---------- download ---------- */
.dl-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.dl {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.dl .os { font-family: var(--mono); font-weight: 700; font-size: 15px; }
.dl .req { color: var(--faint); font-size: 12px; font-family: var(--mono); }
.dl .how { color: var(--dim); font-size: 13px; margin-top: 8px; }
.dl a { color: var(--cyan); font-family: var(--mono); font-size: 12.5px; text-decoration: none; margin-top: 12px; }
.dl a:hover { text-decoration: underline; }

.note {
  margin-top: 26px;
  padding: 16px 20px;
  border: 1px dashed var(--line2);
  border-radius: 10px;
  color: var(--dim);
  font-size: 13.5px;
  background: rgba(34, 211, 238, 0.03);
}
.note b { color: var(--fg); }

/* ---------- contact ---------- */
.contact-box {
  background: linear-gradient(135deg, var(--panel2), var(--panel));
  border: 1px solid var(--line2);
  border-radius: 16px;
  padding: 52px 48px;
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 40px;
  align-items: center;
}
.contact-box h2 { margin-bottom: 10px; }
.contact-box p { color: var(--dim); }
.contact-meta { display: flex; flex-direction: column; gap: 14px; }
.cm {
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--bg2);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 14px 18px;
  font-family: var(--mono);
  font-size: 13px;
}
.cm .lab { color: var(--faint); font-size: 10.5px; letter-spacing: 1.5px; display: block; }
.cm a { color: var(--cyan); text-decoration: none; }
.cm a:hover { text-decoration: underline; }

/* ---------- footer ---------- */
footer { border-top: 1px solid var(--line); padding: 40px 0 48px; }
.foot { display: flex; align-items: center; gap: 24px; flex-wrap: wrap; }
.foot .cop { color: var(--faint); font-size: 12px; font-family: var(--mono); margin-right: auto; }
.foot a { color: var(--dim); font-size: 12.5px; text-decoration: none; font-family: var(--mono); }
.foot a:hover { color: var(--cyan); }

/* ---------- legal pages ---------- */
.legal { padding: 64px 0 90px; max-width: 800px; }
.legal h1 { font-size: 30px; margin-bottom: 6px; }
.legal .upd { font-family: var(--mono); font-size: 12px; color: var(--faint); margin-bottom: 40px; }
.legal h2 { font-size: 19px; margin: 40px 0 12px; padding-top: 8px; }
.legal h2::before { content: "§ "; color: var(--cyan); font-family: var(--mono); }
.legal p, .legal li { color: var(--dim); font-size: 14.5px; }
.legal ul { padding-left: 22px; margin: 10px 0; }
.legal li { margin: 6px 0; }
.legal strong { color: var(--fg); }
.legal .box {
  border: 1px solid var(--line2);
  border-left: 3px solid var(--cyan);
  background: var(--panel);
  border-radius: 8px;
  padding: 16px 20px;
  margin: 18px 0;
}

/* reveal on scroll */
.rv { opacity: 0; transform: translateY(18px); transition: opacity 0.6s ease, transform 0.6s ease; }
.rv.in { opacity: 1; transform: none; }

@media (max-width: 860px) {
  .hero-grid { grid-template-columns: 1fr; gap: 40px; }
  .cards, .dl-grid { grid-template-columns: 1fr; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .contact-box { grid-template-columns: 1fr; padding: 36px 28px; }
  .nav a.link { display: none; }
  .nav a.back { display: inline; }
}