:root {
  --bg: #070b14;
  --panel: #0e1526;
  --ink: #e8eef8;
  --muted: #93a2bb;
  --line: #1d2740;
  --accent: #38bdf8;
  --accent2: #22d3ee;
  --max: 1080px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.65 -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
code { background: #16203a; padding: .1em .4em; border-radius: 4px; font-size: .9em; }

/* nav */
.nav {
  position: sticky; top: 0; z-index: 20;
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 22px; max-width: var(--max); margin: 0 auto;
  backdrop-filter: blur(10px);
  background: rgba(7, 11, 20, .72);
  border-bottom: 1px solid var(--line);
}
.brand { display: flex; align-items: baseline; gap: 10px; font-weight: 700; }
.logo { font-size: 20px; letter-spacing: .5px; background: linear-gradient(90deg, var(--accent), var(--accent2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.brand-txt { font-weight: 500; color: var(--muted); font-size: 14px; }
.nav nav { display: flex; gap: 22px; font-size: 14px; }
.nav nav a { color: var(--muted); transition: color .2s; }
.nav nav a:hover { color: var(--ink); }

/* hero */
.hero { position: relative; min-height: 62vh; display: grid; place-items: center; overflow: hidden; border-bottom: 1px solid var(--line); }
.hero-bg {
  position: absolute; inset: 0;
  background: url("./hero.png") center/cover no-repeat,
              radial-gradient(1200px 500px at 50% -10%, #12314d 0%, var(--bg) 70%);
  opacity: .55;
}
.hero::after { content: ""; position: absolute; inset: 0; background: linear-gradient(180deg, rgba(7,11,20,.2), var(--bg)); }
.hero-inner { position: relative; z-index: 1; text-align: center; padding: 72px 22px; max-width: var(--max); }
.hero h1 { font-size: clamp(34px, 6vw, 58px); margin: 0 0 14px; letter-spacing: .5px; }
.hero h1 span { background: linear-gradient(90deg, var(--accent), var(--accent2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero p { color: var(--muted); font-size: clamp(15px, 2.2vw, 18px); margin: 0 0 28px; }
.hero-actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.btn { padding: 11px 22px; border-radius: 999px; font-size: 15px; border: 1px solid transparent; transition: transform .15s, background .2s; }
.btn:hover { transform: translateY(-1px); }
.btn.primary { background: linear-gradient(90deg, #0ea5e9, #06b6d4); color: #04101c; font-weight: 700; }
.btn.ghost { border-color: var(--line); color: var(--ink); background: rgba(255,255,255,.03); }

/* sections */
.section { max-width: var(--max); margin: 0 auto; padding: 64px 22px; }
.section.alt { background: var(--panel); max-width: none; }
.section.alt > * { max-width: var(--max); margin-left: auto; margin-right: auto; }
.section h2 { font-size: clamp(24px, 3.4vw, 32px); margin: 0 0 10px; }
.lead { color: var(--muted); margin: 0 0 26px; max-width: 760px; }
.muted { opacity: .85; font-size: 14px; }

/* cards */
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 18px; }
.card { background: linear-gradient(180deg, #101a2e, #0b1220); border: 1px solid var(--line); border-radius: 14px; padding: 22px; }
.card h3 { margin: 0 0 8px; font-size: 18px; }
.card .tag { display: inline-block; font-size: 13px; color: var(--accent2); background: rgba(34,211,238,.08); border: 1px solid rgba(34,211,238,.25); padding: 3px 10px; border-radius: 999px; margin: 0 0 14px; }
.card ul { margin: 0; padding-left: 18px; color: var(--muted); font-size: 14.5px; }
.card li { margin: 4px 0; }

/* grid tiles */
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 16px; }
.tile { border: 1px solid var(--line); border-radius: 14px; padding: 20px; background: #0b1220; display: flex; flex-direction: column; gap: 6px; }
.tile b { font-size: 16px; }
.tile span { color: var(--muted); font-size: 14px; }

/* contact */
.contact { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 14px; margin-bottom: 18px; }
.contact div { border: 1px solid var(--line); border-radius: 12px; padding: 16px; background: #0b1220; display: flex; flex-direction: column; gap: 6px; }
.contact b { color: var(--accent2); font-size: 14px; font-weight: 600; }
.contact span { color: var(--muted); font-size: 14.5px; }

/* footer */
.foot { border-top: 1px solid var(--line); padding: 22px; text-align: center; color: var(--muted); font-size: 13px; display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; }
.foot .dot { opacity: .5; }

@media (max-width: 640px) {
  .nav { flex-direction: column; gap: 10px; }
  .nav nav { gap: 16px; font-size: 13px; flex-wrap: wrap; justify-content: center; }
}