/* Strata landing page — dark slate base, mint/coral accents, no web fonts. */
:root {
  --bg: #0c111c;
  --bg2: #121a29;
  --panel: #182335;
  --ink: #e8eef7;
  --ink-dim: #9fb0c4;
  --mint: #56d9a0;
  --coral: #ff8a5c;
  --amber: #f0c860;
  --line: #24314a;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "Segoe UI", system-ui, -apple-system, "Helvetica Neue", Arial, sans-serif;
  overflow-x: hidden;
}

body {
  background:
    radial-gradient(900px 500px at 85% -10%, rgba(255, 138, 92, 0.10), transparent 60%),
    radial-gradient(800px 520px at -10% 30%, rgba(86, 217, 160, 0.09), transparent 60%),
    var(--bg);
}

#topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 22px;
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  background: rgba(12, 17, 28, 0.85);
  backdrop-filter: blur(6px);
  z-index: 5;
}

.brand {
  font-weight: 800;
  letter-spacing: 0.22em;
  font-size: 15px;
  display: flex;
  align-items: center;
  gap: 9px;
}

.brand .mark {
  width: 14px;
  height: 14px;
  display: inline-block;
  background: linear-gradient(135deg, var(--mint) 0 50%, var(--coral) 50% 100%);
  transform: rotate(45deg);
  border-radius: 3px;
}

.brand.small { font-size: 13px; }

.btn {
  display: inline-block;
  padding: 14px 30px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--mint), #37b17f);
  color: #08130d;
  font-weight: 700;
  font-size: 16px;
  text-decoration: none;
  letter-spacing: 0.04em;
  box-shadow: 0 6px 24px rgba(86, 217, 160, 0.35);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.btn:hover { transform: translateY(-2px); box-shadow: 0 10px 30px rgba(86, 217, 160, 0.45); }

.btn.small { padding: 8px 18px; font-size: 13px; box-shadow: none; }

main { max-width: 1060px; margin: 0 auto; padding: 0 22px 40px; }

#hero {
  display: grid;
  grid-template-columns: 1fr 1.25fr;
  gap: 28px;
  align-items: center;
  padding: 46px 0 30px;
}

#hero h1 {
  font-size: clamp(44px, 7vw, 76px);
  margin: 0 0 6px;
  letter-spacing: 0.10em;
  line-height: 1.02;
  background: linear-gradient(100deg, var(--mint) 0%, #a6e6ff 45%, var(--coral) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

#hero .tagline {
  color: var(--ink-dim);
  font-size: 18px;
  margin: 0 0 22px;
  max-width: 30ch;
}

.hero-frame {
  border: 1px solid var(--line);
  border-radius: 14px;
  overflow: hidden;
  background: var(--bg2);
  box-shadow: 0 18px 50px rgba(0, 0, 0, 0.45);
}

#hero-preview {
  display: block;
  width: 100%;
  height: clamp(220px, 34vw, 380px);
}

section h2 {
  font-size: 22px;
  letter-spacing: 0.06em;
  margin: 34px 0 16px;
  color: var(--ink);
}

#gallery {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

#gallery img {
  width: 100%;
  aspect-ratio: 8 / 5;
  object-fit: cover;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: var(--bg2);
}

#features {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

#features li {
  background: var(--panel);
  border: 1px solid var(--line);
  border-left: 3px solid var(--mint);
  border-radius: 10px;
  padding: 14px 16px;
  color: var(--ink-dim);
  line-height: 1.45;
  font-size: 15px;
}

#features li:nth-child(2n) { border-left-color: var(--coral); }
#features li:nth-child(5) { border-left-color: var(--amber); }
#features strong { color: var(--ink); }

#controls {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 8px 18px;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px 18px;
}

.ctl { color: var(--ink-dim); font-size: 15px; padding: 4px 0; }

.ctl .k {
  display: inline-block;
  min-width: 92px;
  font-weight: 700;
  color: var(--amber);
  font-family: ui-monospace, "Cascadia Mono", Consolas, monospace;
  letter-spacing: 0.03em;
}

footer {
  border-top: 1px solid var(--line);
  padding: 30px 22px 46px;
  text-align: center;
}

footer .brand { justify-content: center; margin-bottom: 8px; }
footer p { color: var(--ink-dim); margin: 6px 0 18px; }

@media (max-width: 860px) {
  #hero { grid-template-columns: 1fr; padding-top: 26px; }
  #gallery { grid-template-columns: 1fr; }
  #features { grid-template-columns: 1fr; }
  #controls { grid-template-columns: 1fr; }
}

@media (max-width: 420px) {
  main { padding: 0 14px 30px; }
  #hero .tagline { font-size: 16px; }
  #hero-preview { height: 220px; }
  .btn { padding: 13px 26px; }
}