@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@400;600&family=IBM+Plex+Mono:wght@400;500&display=swap');

:root {
  --bg: #f2f0ea;
  --ink: #1c1f22;
  --muted: #66707a;
  --card: #ffffff;
  --border: #ddd6cb;
  --accent: #f06a3a;
  --accent-soft: rgba(240, 106, 58, 0.12);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: 'Space Grotesk', sans-serif;
  background: var(--bg);
  color: var(--ink);
}

.top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 18px 24px;
  border-bottom: 1px solid var(--border);
  background: var(--card);
  position: sticky;
  top: 0;
  z-index: 10;
}

.brand { font-weight: 600; }

.nav {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.nav a {
  text-decoration: none;
  color: var(--muted);
  font-size: 14px;
}

.nav a.active {
  color: var(--ink);
  font-weight: 600;
}

.list {
  display: grid;
  gap: 8px;
  margin-left: 18px;
  color: var(--muted);
  font-size: 14px;
}

.wrap {
  max-width: 980px;
  margin: 0 auto;
  padding: 36px 20px 64px;
  display: grid;
  gap: 24px;
}

.hero {
  display: grid;
  gap: 12px;
}

.badge {
  width: fit-content;
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--card);
  border: 1px solid var(--border);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.hero-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
}

.hero-card {
  border: 1px solid var(--border);
  background: var(--card);
  border-radius: 14px;
  padding: 12px;
}

.lead { color: var(--muted); }

.card, .ad-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 16px;
  display: grid;
  gap: 12px;
}

.hero-visual img {
  width: 100%;
  height: clamp(180px, 34vw, 360px);
  object-fit: cover;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: #efe9df;
}

.hero-visual a {
  color: var(--accent);
  text-decoration: none;
}

.controls {
  display: grid;
  gap: 12px;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

label { display: grid; gap: 6px; font-size: 14px; color: var(--muted); }
label strong { color: var(--ink); font-size: 13px; }
input[type='range'] { accent-color: var(--accent); }

select {
  padding: 8px 12px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--card);
}

button {
  width: fit-content;
  padding: 10px 18px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--card);
  cursor: pointer;
}

button.primary { background: var(--accent); color: #fff; border-color: transparent; }

.plots { display: grid; gap: 12px; }

svg {
  width: 100%;
  height: 160px;
  background: #fbfaf6;
  border: 1px solid var(--border);
  border-radius: 12px;
}

.compare-canvas {
  width: 100%;
  height: clamp(220px, 40vw, 380px);
  background: #fbfaf6;
  border: 1px solid var(--border);
  border-radius: 12px;
}

.math-block {
  font-family: 'IBM Plex Mono', monospace;
  background: #f7f3ee;
  border: 1px dashed var(--border);
  border-radius: 12px;
  padding: 12px;
  font-size: 13px;
  display: grid;
  gap: 8px;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 14px;
}

.faq {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 12px;
}

.muted { color: var(--muted); font-size: 14px; }

.footer {
  text-align: center;
  padding: 24px;
  color: var(--muted);
  font-size: 13px;
}

@media (max-width: 720px) {
  .top { align-items: flex-start; gap: 10px; flex-direction: column; }
}