:root {
  --bg: #0c0d10;
  --bg-elev: #14161b;
  --fg: #e7e8ec;
  --fg-dim: #8b8f99;
  --line: #23262d;
  --accent: #c7f06e;       /* deep-learning accent — soft lime */
  --accent-2: #6fdc8c;     /* climbing accent — pine green (climb3d brand) */
  --accent-2-soft: rgba(111, 220, 140, 0.12);
  --radius: 18px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: ui-sans-serif, -apple-system, BlinkMacSystemFont, "Inter",
               "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  font-feature-settings: "ss01", "cv11";
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  min-height: 100%;
}

body {
  background:
    radial-gradient(1200px 600px at 20% -10%, rgba(199, 240, 110, 0.08), transparent 60%),
    radial-gradient(900px 500px at 100% 10%, rgba(111, 220, 140, 0.06), transparent 60%),
    var(--bg);
}

main {
  max-width: 980px;
  margin: 0 auto;
  padding: 96px 28px 64px;
}

/* Hero -------------------------------------------------------------- */
.hero { margin-bottom: 64px; }

.kicker {
  display: inline-block;
  font-family: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--fg-dim);
  border: 1px solid var(--line);
  padding: 4px 10px;
  border-radius: 999px;
  margin-bottom: 28px;
}

h1 {
  font-size: clamp(40px, 6vw, 64px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  margin: 0 0 16px;
  font-weight: 600;
}

.lede {
  font-size: clamp(16px, 1.4vw, 18px);
  color: var(--fg-dim);
  max-width: 56ch;
  line-height: 1.55;
  margin: 0;
}

.lede__lab {
  color: var(--fg);
}

.lede__group {
  font-size: clamp(13px, 1.05vw, 14px);
  color: var(--fg-dim);
  margin: 4px 0 0;
  letter-spacing: 0.01em;
}

.topics {
  list-style: none;
  padding: 0;
  margin: 20px 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.topics li {
  font-family: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 12px;
  letter-spacing: 0.02em;
  color: var(--fg-dim);
  border: 1px solid var(--line);
  padding: 4px 10px;
  border-radius: 999px;
}

/* Cards ------------------------------------------------------------- */
.cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  margin-bottom: 80px;
}

@media (max-width: 720px) {
  .cards { grid-template-columns: 1fr; }
  main { padding-top: 56px; }
}

.card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 28px;
  background: var(--bg-elev);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--fg);
  text-decoration: none;
  overflow: hidden;
  transition: transform 200ms ease, border-color 200ms ease, background 200ms ease;
}

.card::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: radial-gradient(400px 200px at 100% 0%, var(--card-glow, transparent), transparent 60%);
  opacity: 0;
  transition: opacity 200ms ease;
}

.card--dl    { --card-glow: rgba(199, 240, 110, 0.18); }
.card--climb { --card-glow: rgba(111, 220, 140, 0.18); }

.card:hover {
  transform: translateY(-2px);
  border-color: #353841;
}
.card:hover::after { opacity: 1; }

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

.card__head {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.card__tag {
  font-family: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 4px 8px;
  border-radius: 6px;
  background: rgba(199, 240, 110, 0.12);
  color: var(--accent);
}
.card__tag--beta {
  background: var(--accent-2-soft);
  color: var(--accent-2);
}

.card__arrow {
  font-size: 22px;
  color: var(--fg-dim);
  transition: transform 200ms ease, color 200ms ease;
}
.card:hover .card__arrow {
  transform: translateX(4px);
  color: var(--fg);
}

.card h2 {
  font-size: 26px;
  margin: 4px 0 0;
  letter-spacing: -0.01em;
  font-weight: 600;
}

.card p {
  color: var(--fg-dim);
  line-height: 1.55;
  margin: 0;
  font-size: 15px;
}

.card__chips {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.card__chips li {
  font-family: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 11px;
  letter-spacing: 0.02em;
  color: var(--fg-dim);
  border: 1px solid var(--line);
  padding: 3px 8px;
  border-radius: 999px;
}

.card__host {
  margin-top: auto;
  font-family: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 12px;
  color: var(--fg-dim);
}

/* Footer ------------------------------------------------------------ */
footer {
  color: var(--fg-dim);
  font-size: 13px;
  display: flex;
  gap: 10px;
  align-items: center;
  padding-top: 24px;
  border-top: 1px solid var(--line);
}

footer a {
  color: var(--fg-dim);
  text-decoration: none;
  border-bottom: 1px dotted var(--line);
}
footer a:hover { color: var(--fg); border-bottom-color: var(--fg-dim); }

.dot { opacity: 0.5; }