@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600&family=Fira+Code:wght@400;500&display=swap');

:root {
    --bg: #111111;
    --surface: #1c1c1c;
    --text: #e5e5e5;
    --muted: #a3a3a3;
    --accent: #8a8a8a;
    --border: #2a2a2a;
}

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

body {
    font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.7;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 40px 0;
}

nav {
    display: flex;
    gap: 24px;
    padding-bottom: 24px;
    border-bottom: 1px solid var(--border);
    margin-bottom: 40px;
}

nav a {
    color: var(--text);
    text-decoration: none;
    font-weight: 500;
}

nav a:hover {
    color: var(--accent);
}

h1 {
    font-size: 2.2rem;
    margin-bottom: 20px;
}

h2 {
    font-size: 1.5rem;
    margin: 40px 0 20px;
}

p {
    margin-bottom: 16px;
    color: var(--muted);
}

.lab-layout {
  display: grid;
  grid-template-columns: 1fr 900px 1fr;
  gap: 40px;
  align-items: start;
}

.card {
    background: var(--surface);
    border: 1px solid var(--border);
    padding: 24px;
    border-radius: 8px;
    margin-bottom: 20px;
}


.lab-content {
  grid-column: 2;
}

.card h3 {
    margin-bottom: 10px;
}

a {
    color: var(--accent);
}

ul {
    margin-left: 20px;
    margin-bottom: 20px;
}

footer {
    margin-top: 60px;
    padding-top: 20px;
    border-top: 1px solid var(--border);
    color: var(--muted);
    font-size: 0.9rem;
}




/* --- Lab layout helpers --- */
.hero {
  padding: 28px 0 10px;
  margin-bottom: 18px;
}

.kicker {
  display: inline-block;
  font-size: 0.85rem;
  color: var(--muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 10px;
}

.subtitle {
  max-width: 70ch;
  color: var(--muted);
}

.grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  align-items: start;
}

.col-4, .col-8 { width: 100%; }

.toc {
  grid-column: 1;
  justify-self: end;
  width: 220px;
  position: sticky;
  top: 40px;
}

.toc h3 {
  margin-bottom: 10px;
}

.toc ul {
  list-style: none;
  margin-left: 0;
  padding-left: 0;
}

.toc li {
  margin: 10px 0;
}

.toc a {
  color: var(--muted);
  text-decoration: none;
}

.toc a:hover {
  color: var(--text);
}

/* Buttons / actions */
.actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: 8px;
  text-decoration: none;
  color: var(--text);
  background: transparent;
}

.btn:hover {
  border-color: var(--accent);
}

.btn-primary {
  background: var(--text);
  color: var(--bg);
  border-color: var(--text);
}

.btn-primary:hover {
  opacity: 0.9;
}

/* Responsive two-column layout on desktop */


nav a.active {
  color: var(--text);
  border-bottom: 2px solid var(--accent);
  padding-bottom: 6px;
}