:root {
  --brand: #211FF4;
  --brand-2: #3A3AFF;
  --dark: #03031A;
  --ink: #1a1a24;
  --muted: #5b5b6b;
  --line: #e7e7f0;
  --bg: #f6f6fb;
  --card: #ffffff;
  --amber: #b7791f;
  --radius: 14px;
  --maxw: 1080px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Inter", "Segoe UI", system-ui, -apple-system, Roboto, Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--brand); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* --- Header / nav --- */
.nav {
  position: sticky; top: 0; z-index: 10;
  background: rgba(3, 3, 26, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}
.nav .wrap { display: flex; align-items: center; justify-content: space-between; height: 62px; }
.nav img { height: 24px; display: block; }
.nav .links { display: flex; gap: 22px; align-items: center; }
.nav .links a { color: #c9c9e6; font-size: 14px; font-weight: 500; }
.nav .links a:hover { color: #fff; text-decoration: none; }
.nav .links .cta {
  background: var(--brand); color: #fff; padding: 8px 16px; border-radius: 9px; font-weight: 600;
}
.nav .links .cta:hover { background: var(--brand-2); }

/* --- Hero --- */
.hero {
  background: radial-gradient(1200px 500px at 70% -10%, #1a1a5e 0%, transparent 60%), var(--dark);
  color: #fff; padding: 74px 0 84px;
  border-bottom: 1px solid rgba(255,255,255,0.06);
}
.hero img.mark { height: 40px; margin-bottom: 26px; }
.badge {
  display: inline-block; background: var(--brand); color: #fff;
  font-size: 12px; font-weight: 700; padding: 4px 11px; border-radius: 20px; letter-spacing: .3px;
  vertical-align: middle; margin-left: 10px;
}
.hero h1 { font-size: 44px; line-height: 1.12; margin: 0 0 14px; font-weight: 800; letter-spacing: -0.5px; }
.hero p.lead { font-size: 19px; color: #b9b9d6; max-width: 620px; margin: 0 0 30px; }
.cta-row { display: flex; gap: 14px; align-items: center; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; gap: 9px;
  background: var(--brand); color: #fff; font-weight: 700; font-size: 16px;
  padding: 14px 24px; border-radius: 11px; border: 0; cursor: pointer;
  transition: background .15s ease, transform .05s ease;
}
.btn:hover { background: var(--brand-2); text-decoration: none; }
.btn:active { transform: translateY(1px); }
.btn.ghost { background: transparent; border: 1px solid rgba(255,255,255,0.22); color: #dcdcf2; }
.btn.ghost:hover { background: rgba(255,255,255,0.06); }
.hero .meta { margin-top: 18px; font-size: 13px; color: #8a8ab0; }
.hero .meta code { color: #b9b9e6; background: rgba(255,255,255,0.06); padding: 2px 7px; border-radius: 6px; font-size: 12px; }

/* --- Sections --- */
section { padding: 66px 0; }
section h2 { font-size: 30px; font-weight: 800; letter-spacing: -0.4px; margin: 0 0 10px; color: var(--dark); }
section .sub { color: var(--muted); font-size: 16px; max-width: 640px; margin: 0 0 34px; }

.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 18px; }
.card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 24px; transition: box-shadow .15s ease, transform .1s ease;
}
.card:hover { box-shadow: 0 10px 30px rgba(3,3,26,0.07); transform: translateY(-2px); }
.card .ic { font-size: 26px; }
.card h3 { margin: 12px 0 8px; font-size: 18px; color: var(--dark); }
.card p { margin: 0; color: var(--muted); font-size: 14.5px; }

.alt { background: #fff; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }

/* Lifecycle steps */
.steps { display: flex; gap: 12px; flex-wrap: wrap; margin-top: 8px; }
.step {
  flex: 1 1 200px; background: var(--bg); border: 1px solid var(--line);
  border-radius: 12px; padding: 18px 20px;
}
.step .n { font-size: 12px; font-weight: 800; color: var(--brand); }
.step h4 { margin: 6px 0 4px; font-size: 16px; color: var(--dark); }
.step p { margin: 0; font-size: 13.5px; color: var(--muted); }

.principles { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px,1fr)); gap: 14px; margin-top: 22px; }
.principle { display: flex; gap: 12px; align-items: flex-start; }
.principle .dot { color: var(--brand); font-weight: 800; }
.principle b { color: var(--dark); }
.principle span { color: var(--muted); font-size: 14px; }

/* Changelog */
.release { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 28px; }
.release .rhead { display: flex; align-items: baseline; gap: 12px; flex-wrap: wrap; margin-bottom: 6px; }
.release .ver { font-size: 22px; font-weight: 800; color: var(--dark); }
.release .date { color: var(--muted); font-size: 14px; }
.release .tag { background: #e9e9ff; color: var(--brand); font-size: 12px; font-weight: 700; padding: 3px 10px; border-radius: 20px; }
.release h4 { margin: 20px 0 8px; font-size: 14px; text-transform: uppercase; letter-spacing: .6px; color: var(--muted); }
.release ul { margin: 0; padding-left: 20px; }
.release li { margin: 5px 0; color: var(--ink); font-size: 14.5px; }
.note {
  margin-top: 22px; background: #fff8ec; border: 1px solid #f0e0c0; color: var(--amber);
  border-radius: 10px; padding: 12px 16px; font-size: 13.5px;
}

/* Download panel */
.download-panel {
  background: linear-gradient(180deg, #06062a, var(--dark)); color: #fff;
  border-radius: 18px; padding: 34px; display: flex; gap: 26px; align-items: center; flex-wrap: wrap;
  justify-content: space-between; border: 1px solid rgba(255,255,255,0.08);
}
.download-panel h3 { margin: 0 0 6px; font-size: 22px; }
.download-panel p { margin: 0; color: #b9b9d6; font-size: 14.5px; }
.download-panel .hash { margin-top: 12px; font-size: 12px; color: #8a8ab0; word-break: break-all; }
.download-panel .hash code { color: #b9b9e6; }

/* Footer */
footer { background: var(--dark); color: #9a9ac2; padding: 40px 0; font-size: 13.5px; border-top: 1px solid rgba(255,255,255,0.06); }
footer .wrap { display: flex; justify-content: space-between; gap: 20px; flex-wrap: wrap; align-items: center; }
footer a { color: #c9c9e6; }
footer img { height: 20px; opacity: .9; }

@media (max-width: 640px) {
  .hero h1 { font-size: 34px; }
  .nav .links a:not(.cta) { display: none; }
  section { padding: 48px 0; }
}