:root {
  --bg: #06120f;
  --bg-2: #0a1c17;
  --panel: rgba(12, 32, 26, 0.72);
  --line: rgba(124, 255, 58, 0.18);
  --text: #d8f5e3;
  --muted: #8fb5a2;
  --green: #7cff3a;
  --lime: #c6ff1a;
  --yellow: #ffd60a;
  --blue: #1fa2ff;
  --radius: 14px;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Consolas, monospace;
  --display: "Chakra Petch", "Inter", system-ui, sans-serif;
  --sans: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: radial-gradient(1200px 600px at 70% -10%, rgba(31, 162, 255, 0.12), transparent 60%),
              radial-gradient(900px 500px at 0% 30%, rgba(124, 255, 58, 0.08), transparent 60%),
              var(--bg);
  color: var(--text);
  font-family: var(--sans);
  line-height: 1.6;
  overflow-x: hidden;
}

#rain {
  position: fixed; inset: 0;
  width: 100%; height: 100%;
  z-index: 0; opacity: 0.18; pointer-events: none;
}

a { color: var(--green); }
code { font-family: var(--mono); color: var(--lime); }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

/* nav */
.nav {
  position: sticky; top: 0; z-index: 10;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  padding: 12px clamp(16px, 4vw, 48px);
  background: rgba(6, 18, 15, 0.82);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--text); font-family: var(--display); font-weight: 700; letter-spacing: 0.04em; }
.brand img { border-radius: 8px; }
.brand b { color: var(--green); }
.brand i { font-style: normal; color: var(--yellow); }
.nav nav { display: flex; gap: clamp(10px, 2vw, 24px); align-items: center; flex-wrap: wrap; justify-content: flex-end; }
.nav nav a { color: var(--muted); text-decoration: none; font-family: var(--mono); font-size: 0.85rem; }
.nav nav a:hover, .nav nav a:focus-visible { color: var(--green); }
.nav nav a.nav-cta { color: var(--bg); background: var(--green); padding: 6px 12px; border-radius: 8px; font-weight: 600; }

main, .foot { position: relative; z-index: 1; }

/* hero */
.hero {
  display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr);
  gap: clamp(24px, 5vw, 64px); align-items: center;
  max-width: 1180px; margin: 0 auto;
  padding: clamp(40px, 8vw, 96px) clamp(16px, 4vw, 48px);
}
.hero-logo img {
  width: 100%; height: auto; display: block;
  border-radius: 28px;
  box-shadow: 0 0 0 1px var(--line), 0 0 60px rgba(124, 255, 58, 0.25), 0 0 120px rgba(31, 162, 255, 0.15);
  animation: float 6s ease-in-out infinite;
}
@keyframes float { 50% { transform: translateY(-10px); } }

.kicker { font-family: var(--mono); color: var(--blue); margin: 0 0 8px; }
h1 {
  font-family: var(--display); font-weight: 700;
  font-size: clamp(2.6rem, 8vw, 5.2rem); line-height: 1; margin: 0 0 16px;
  letter-spacing: 0.02em;
  text-shadow: 0 0 24px rgba(124, 255, 58, 0.25);
}
h1 .g { color: var(--green); }
h1 .y { color: var(--yellow); font-size: 0.6em; vertical-align: middle; }
.lead { color: var(--muted); font-size: 1.1rem; max-width: 52ch; }

.term {
  font-family: var(--mono); font-size: 0.95rem;
  background: #020806; border: 1px solid var(--line); border-radius: 10px;
  padding: 12px 16px; margin: 20px 0; overflow-x: auto; white-space: nowrap;
}
.term .p { color: var(--green); }
.cursor { color: var(--green); animation: blink 1s steps(1) infinite; }
@keyframes blink { 50% { opacity: 0; } }

.ctas { display: flex; flex-wrap: wrap; gap: 12px; }
.btn {
  display: inline-block; font-family: var(--mono); font-weight: 600; font-size: 0.95rem;
  padding: 12px 18px; border-radius: 10px; text-decoration: none; cursor: pointer;
  border: 1px solid var(--green); transition: transform .15s ease, box-shadow .15s ease;
}
.btn:hover, .btn:focus-visible { transform: translateY(-2px); box-shadow: 0 0 24px rgba(124, 255, 58, 0.35); }
.btn.primary { background: var(--green); color: var(--bg); }
.btn.ghost { background: transparent; color: var(--green); }

/* blocks */
.block { max-width: 1180px; margin: 0 auto; padding: clamp(32px, 6vw, 64px) clamp(16px, 4vw, 48px); }
h2 { font-family: var(--display); font-size: clamp(1.6rem, 4vw, 2.2rem); margin: 0 0 24px; text-transform: uppercase; letter-spacing: 0.06em; }
.hash { color: var(--green); font-family: var(--mono); }
h3 { font-family: var(--display); margin: 0 0 8px; color: var(--lime); }

.grid { display: grid; gap: 16px; }
.grid.three { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }
.grid.cats { grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); }

.card, .cat {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 20px; backdrop-filter: blur(4px);
}
.card p, .cat p { margin: 0; color: var(--muted); }
.cat { transition: border-color .2s, transform .2s; }
.cat:hover { border-color: var(--green); transform: translateY(-3px); }
.tag {
  display: inline-block; font-family: var(--mono); font-weight: 600; font-size: 0.85rem;
  color: var(--bg); background: var(--yellow); border-radius: 6px; padding: 2px 8px; margin-bottom: 10px;
}
.cat:nth-child(3n+2) .tag { background: var(--green); }
.cat:nth-child(3n) .tag { background: var(--blue); }

.timeline { list-style: none; margin: 0; padding: 0; border-left: 2px solid var(--line); }
.timeline li { position: relative; padding: 0 0 24px 24px; }
.timeline li::before {
  content: ""; position: absolute; left: -7px; top: 6px; width: 12px; height: 12px;
  border-radius: 50%; background: var(--green); box-shadow: 0 0 12px var(--green);
}
.timeline b { display: block; font-family: var(--display); color: var(--text); }
.timeline span { color: var(--muted); }

.challenge p + p { margin-top: 8px; }
.hint { font-size: 0.9rem; }
#flag-form { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 16px; }
#flag-form input {
  flex: 1 1 240px; min-width: 0;
  font-family: var(--mono); font-size: 1rem; color: var(--text);
  background: #020806; border: 1px solid var(--line); border-radius: 10px; padding: 12px 14px;
}
#flag-form input:focus { outline: none; border-color: var(--green); box-shadow: 0 0 0 3px rgba(124, 255, 58, 0.2); }
#flag-result { font-family: var(--mono); min-height: 1.6em; margin-top: 12px !important; }
#flag-result.ok { color: var(--green); }
#flag-result.err { color: #ff6b6b; }

.join p { margin-bottom: 16px !important; }
.fine { font-size: 0.82rem; color: var(--muted); }

.foot { text-align: center; padding: 40px 16px 56px; border-top: 1px solid var(--line); font-family: var(--mono); color: var(--muted); }
.foot p { margin: 4px 0; }

:focus-visible { outline: 2px solid var(--yellow); outline-offset: 3px; }

@media (max-width: 820px) {
  .hero { grid-template-columns: 1fr; text-align: center; }
  .hero-logo { max-width: 360px; margin: 0 auto; }
  .lead { margin: 0 auto; }
  .ctas { justify-content: center; }
  .nav nav a:not(.nav-cta) { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .hero-logo img, .cursor { animation: none; }
  #rain { display: none; }
}