:root {
  --ink: #eef3ff;
  --muted: #8b9bb8;
  --faint: #5a6a86;
  --bg: #03060f;
  --bg2: #070d1c;
  --lime: #b8f23a;
  --lime2: #8fd41a;
  --ice: #7ee7ff;
  --hot: #ff5a36;
  --nebula: #1a3a5c;
  --line: rgba(126, 231, 255, 0.14);
  --head: "Syne", system-ui, sans-serif;
  --body: "IBM Plex Sans", system-ui, sans-serif;
  --max: 1100px;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font-family: var(--body); font-size: 17px; line-height: 1.5;
  min-height: 100vh; overflow-x: hidden;
}
a { color: var(--lime); text-decoration: none; }
a:hover { color: #fff; }
.wrap { width: min(var(--max), calc(100% - 32px)); margin: 0 auto; position: relative; z-index: 2; }
nav {
  position: sticky; top: 0; z-index: 30;
  backdrop-filter: blur(14px);
  background: rgba(3, 6, 15, 0.78);
  border-bottom: 1px solid var(--line);
}
nav .row { display: flex; align-items: center; justify-content: space-between; gap: 12px; min-height: 58px; flex-wrap: wrap; }
.brand { font-family: var(--head); font-weight: 800; letter-spacing: -0.03em; color: var(--ink); font-size: 1.05rem; }
.brand span { color: var(--lime); }
.nav-links { display: flex; gap: 12px; flex-wrap: wrap; align-items: center; font-size: 0.88rem; }
.nav-links a { color: var(--muted); }
.nav-links a:hover, .nav-links a[aria-current] { color: var(--lime); }
.lang-switch { display: flex; gap: 4px; align-items: center; }
.lang-switch a {
  font-size: 0.72rem; letter-spacing: 0.06em; text-transform: uppercase;
  color: var(--faint); padding: 4px 6px; border: 1px solid transparent; border-radius: 3px;
}
.lang-switch a[aria-current] { color: var(--ice); border-color: var(--line); }
.lang-switch a:hover { color: var(--ink); }

/* —— cosmic portal hero —— */
.hero-cosmic {
  position: relative; isolation: isolate;
  min-height: min(92vh, 760px);
  display: flex; align-items: flex-end;
  padding: 0 0 56px;
  border-bottom: 1px solid var(--line);
  overflow: hidden;
}
.hero-cosmic .sky {
  position: absolute; inset: 0; z-index: 0;
  background:
    radial-gradient(ellipse 70% 55% at 70% 20%, rgba(26, 58, 92, 0.55), transparent 60%),
    radial-gradient(ellipse 45% 40% at 15% 70%, rgba(184, 242, 58, 0.12), transparent 55%),
    radial-gradient(ellipse 50% 35% at 85% 80%, rgba(255, 90, 54, 0.14), transparent 50%),
    linear-gradient(180deg, #010309 0%, #03060f 55%, #050a16 100%);
}
.hero-cosmic canvas#cosmos {
  position: absolute; inset: 0; width: 100%; height: 100%; z-index: 1; display: block;
}
.hero-cosmic .veil {
  position: absolute; inset: 0; z-index: 1; pointer-events: none;
  background: linear-gradient(180deg, transparent 40%, rgba(3,6,15,0.75) 78%, var(--bg) 100%);
}
.hero-cosmic .wrap { z-index: 2; padding-top: clamp(72px, 14vh, 120px); }
.eyebrow {
  font-size: 0.78rem; letter-spacing: 0.16em; text-transform: uppercase;
  color: var(--ice); font-weight: 600; margin: 0 0 16px;
}
.hero-cosmic .brand-hero {
  font-family: var(--head); font-weight: 800;
  font-size: clamp(2.6rem, 8vw, 4.4rem); line-height: 0.95;
  letter-spacing: -0.045em; margin: 0 0 18px; max-width: 12ch;
  text-shadow: 0 0 40px rgba(184,242,58,0.25);
}
.hero-cosmic .brand-hero span { color: var(--lime); }
.hero-cosmic h1 {
  font-family: var(--head); font-weight: 800;
  font-size: clamp(1.35rem, 3.2vw, 1.85rem); line-height: 1.15;
  letter-spacing: -0.03em; margin: 0 0 12px; max-width: 22ch;
  color: var(--ink);
}
.hero-cosmic .lede { color: var(--muted); max-width: 40ch; margin: 0 0 28px; font-size: 1.05rem; }
.ctas { display: flex; flex-wrap: wrap; gap: 10px; }
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 12px 18px; border-radius: 4px; font-weight: 700; font-size: 0.95rem;
  border: 1px solid transparent; cursor: pointer; font-family: var(--body);
}
.btn-primary { background: var(--lime); color: #081208; }
.btn-primary:hover { background: #d4ff5c; color: #081208; }
.btn-ghost { border-color: var(--line); color: var(--ink); background: rgba(7,13,28,0.55); }
.btn-ghost:hover { border-color: var(--ice); color: var(--ice); }
.btn-hot { background: var(--hot); color: #fff; }
.btn-hot:hover { filter: brightness(1.08); color: #fff; }

.catalog-head {
  padding: 48px 0 8px;
  font-family: var(--head); font-weight: 800; font-size: 1.15rem;
  letter-spacing: -0.02em; color: var(--muted);
}
.grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 14px; padding: 16px 0 72px;
}
.card {
  display: flex; flex-direction: column; gap: 8px;
  padding: 20px 18px 18px; border: 1px solid var(--line);
  background:
    linear-gradient(155deg, rgba(126,231,255,0.07), transparent 45%),
    linear-gradient(320deg, rgba(184,242,58,0.05), transparent 40%),
    var(--bg2);
  min-height: 188px; transition: border-color .18s, transform .18s, box-shadow .18s;
  position: relative; overflow: hidden;
}
.card::before {
  content: ""; position: absolute; top: -20%; right: -15%; width: 90px; height: 90px;
  background: radial-gradient(circle, rgba(184,242,58,0.18), transparent 70%);
  pointer-events: none;
}
.card:hover {
  border-color: rgba(184,242,58,0.55);
  transform: translateY(-3px);
  box-shadow: 0 12px 40px rgba(0,0,0,0.35), 0 0 24px rgba(126,231,255,0.08);
}
.card .num {
  font-family: var(--head); font-size: 0.78rem; color: var(--ice); letter-spacing: 0.1em;
}
.card h3 {
  font-family: var(--head); font-size: 1.22rem; letter-spacing: -0.02em;
  margin: 0; line-height: 1.15; color: var(--ink);
}
.card p { margin: 0; color: var(--muted); font-size: 0.92rem; flex: 1; }
.card .meta { font-size: 0.78rem; color: var(--faint); }

.section { padding: 40px 0 64px; }
.lesson-hero h1 {
  font-family: var(--head); font-weight: 800;
  font-size: clamp(1.9rem, 4.5vw, 2.8rem); letter-spacing: -0.03em;
  margin: 0 0 10px; line-height: 1.05; max-width: 16ch;
}
.layout {
  display: grid; grid-template-columns: 1.05fr 1fr; gap: 28px; align-items: start;
}
@media (max-width: 860px) { .layout { grid-template-columns: 1fr; } }
.reel {
  position: relative; aspect-ratio: 9 / 16; max-height: 560px; width: min(100%, 320px);
  margin: 0 auto; border: 1px solid var(--line); background: #02050c; overflow: hidden;
  border-radius: 12px;
  box-shadow: 0 0 48px rgba(126,231,255,0.08), inset 0 0 40px rgba(184,242,58,0.04);
}
.reel canvas { width: 100%; height: 100%; display: block; }
.reel .cap {
  position: absolute; left: 12px; right: 12px; bottom: 16px;
  font-family: var(--head); font-size: 1.15rem; font-weight: 800;
  letter-spacing: -0.02em; text-shadow: 0 2px 12px #000;
  transition: opacity .25s;
}
.reel .progress {
  position: absolute; left: 0; right: 0; top: 0; height: 3px; background: rgba(255,255,255,0.1);
}
.reel .progress > i {
  display: block; height: 100%; width: 0; background: linear-gradient(90deg, var(--lime), var(--ice));
}
.panel {
  border: 1px solid var(--line); padding: 18px; background: var(--bg2);
}
.panel h2 {
  font-family: var(--head); font-size: 1.1rem; margin: 0 0 10px; letter-spacing: -0.02em;
}
.panel pre {
  margin: 0 0 12px; padding: 12px; background: #02050c; border: 1px solid var(--line);
  font-size: 0.78rem; overflow: auto; max-height: 220px; color: #c8e8d8;
  white-space: pre-wrap; word-break: break-word;
}
.steps { margin: 0 0 18px; padding-left: 18px; color: var(--muted); }
.steps li { margin: 6px 0; }
.note { color: var(--faint); font-size: 0.85rem; margin-top: 18px; }
footer {
  border-top: 1px solid var(--line); padding: 28px 0 40px; color: var(--faint); font-size: 0.88rem;
}
footer .row { display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap; }
@media (prefers-reduced-motion: reduce) {
  .card:hover { transform: none; }
}