:root {
  --bg: #0f1115;
  --surface: #161a22;
  --nav-surface: #121620;
  --ink: #e6e9ef;
  --muted: #aab1c3;
  --muted-deep: #6f778c;
  --accent: #c14a3a;
  --accent-bright: #e05f4d;
  --accent-shadow: #4a1e1a;
  --line: #23293a;
  --shadow: 0 24px 50px rgba(10, 12, 18, 0.55);
  --font-serif: "Fraunces", "Iowan Old Style", "Palatino", "Times", serif;
  --font-sans: "Space Grotesk", "Avenir Next", "Segoe UI", sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at 12% 10%, rgba(193, 74, 58, 0.25), transparent 55%),
    radial-gradient(circle at 82% 12%, rgba(74, 30, 26, 0.4), transparent 60%),
    var(--bg);
  color: var(--ink);
  font-family: var(--font-sans);
}

a {
  color: inherit;
  text-decoration: none;
}

.page {
  min-height: 100vh;
  display: grid;
  grid-template-rows: auto 1fr auto;
}

.chrome {
  padding: 2.5rem clamp(1.5rem, 4vw, 4rem) 2rem;
  border-bottom: 1px solid var(--line);
  background: rgba(18, 22, 32, 0.88);
  backdrop-filter: blur(6px);
}

.brand {
  display: flex;
  gap: 1.5rem;
  align-items: center;
}

.brand-mark {
  width: 56px;
  height: 56px;
  border-radius: 16px;
  background: var(--accent);
  color: var(--ink);
  display: grid;
  place-items: center;
  font-family: var(--font-serif);
  font-weight: 700;
  letter-spacing: 0.08em;
  box-shadow: var(--shadow);
}

.brand-kicker {
  margin: 0;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.3em;
  color: var(--muted-deep);
}

.brand-title {
  margin: 0.35rem 0 0;
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  color: var(--accent-bright);
}

.nav {
  margin-top: 1.5rem;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  font-weight: 600;
}

.nav a {
  padding: 0.4rem 0.9rem;
  border-radius: 999px;
  border: 1px solid transparent;
  transition: border-color 150ms ease, transform 150ms ease;
}

.nav a:hover {
  border-color: var(--accent-bright);
  transform: translateY(-2px);
}

.content {
  padding: 2.5rem clamp(1.5rem, 4vw, 4rem) 3rem;
}

.shell {
  display: grid;
  grid-template-columns: minmax(180px, 220px) minmax(0, 1fr) minmax(180px, 240px);
  gap: 2rem;
  padding: 2.5rem clamp(1.5rem, 4vw, 4rem) 3rem;
}

.side {
  position: sticky;
  top: 1.5rem;
  align-self: start;
  padding: 1.5rem;
  border-radius: 20px;
  background: rgba(18, 22, 32, 0.92);
  border: 1px solid var(--line);
  font-size: 0.95rem;
  box-shadow: 0 12px 22px rgba(10, 12, 18, 0.4);
}

.side ul {
  list-style: none;
  padding: 0;
  margin: 0 0 1.5rem;
  display: grid;
  gap: 0.6rem;
}

.side a {
  display: inline-flex;
  gap: 0.4rem;
  align-items: center;
}

.side-title {
  margin: 0 0 0.8rem;
  font-family: var(--font-serif);
  color: var(--accent);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-size: 0.75rem;
}

.side-card {
  padding: 1rem;
  border-radius: 16px;
  background: rgba(22, 26, 34, 0.85);
  border: 1px dashed var(--line);
}

.content {
  padding: 0;
}

.hero {
  display: grid;
  gap: 1.5rem;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  align-items: center;
  margin-bottom: 2.5rem;
}

.hero h2 {
  font-family: var(--font-serif);
  font-size: clamp(2rem, 4vw, 3rem);
  margin: 0;
}

.hero p {
  margin: 0;
  color: var(--muted);
  line-height: 1.6;
}

.card-grid {
  display: grid;
  gap: 1.5rem;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.card {
  padding: 1.5rem;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 20px;
  box-shadow: 0 16px 30px rgba(10, 12, 18, 0.35);
}

.card h3 {
  margin-top: 0;
  font-family: var(--font-serif);
}

.card ul {
  padding-left: 1.1rem;
  margin-bottom: 0;
  color: var(--muted);
}

.section-title {
  font-family: var(--font-serif);
  margin: 0 0 1rem;
  font-size: 1.5rem;
}

.kicker {
  text-transform: uppercase;
  letter-spacing: 0.3em;
  font-size: 0.75rem;
  color: var(--muted-deep);
  margin: 0 0 0.6rem;
}

.algorithm-content {
  margin-top: 2rem;
  display: grid;
  gap: 2rem;
}

.code-block {
  margin: 0;
  padding: 1.5rem;
  background: #0c0f14;
  border-radius: 16px;
  border: 1px solid var(--line);
  overflow-x: auto;
  font-size: 0.9rem;
  line-height: 1.5;
  color: var(--ink);
}

.code-block code {
  font-family: "JetBrains Mono", "SFMono-Regular", "Menlo", monospace;
}

.footer {
  padding: 2rem clamp(1.5rem, 4vw, 4rem);
  border-top: 1px solid var(--line);
  color: var(--muted-deep);
  font-size: 0.9rem;
}

@media (max-width: 720px) {
  .chrome {
    padding-top: 2rem;
  }

  .brand {
    flex-direction: column;
    align-items: flex-start;
  }

  .shell {
    grid-template-columns: 1fr;
  }

  .side {
    position: static;
  }
}