:root {
  color-scheme: dark;
  --canvas: #020617;
  --surface: #111827;
  --surface-soft: #172033;
  --text: #f8fafc;
  --muted: #cbd5e1;
  --cyan: #38bdf8;
  --green: #22c55e;
  --rule: #334155;
}

* {
  box-sizing: border-box;
}

html {
  background: var(--canvas);
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.65;
}

body {
  margin: 0;
}

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

a:focus-visible {
  outline: 3px solid var(--green);
  outline-offset: 4px;
}

.skip-link {
  left: 1rem;
  position: absolute;
  top: -5rem;
}

.skip-link:focus {
  top: 1rem;
}

.shell {
  margin: 0 auto;
  max-width: 54rem;
  padding: 2rem 1.25rem 5rem;
}

header {
  border-bottom: 1px solid var(--rule);
  margin-bottom: 2.5rem;
  padding-bottom: 2rem;
}

.mark {
  align-items: center;
  color: var(--muted);
  display: flex;
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-size: 0.82rem;
  gap: 0.75rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.prompt {
  color: var(--cyan);
  font-size: 1.35rem;
  font-weight: 800;
}

h1 {
  font-size: clamp(2.25rem, 7vw, 4.25rem);
  letter-spacing: -0.055em;
  line-height: 1;
  margin: 1.25rem 0 1rem;
}

.summary {
  color: var(--muted);
  font-size: 1.08rem;
  margin: 0;
  max-width: 44rem;
}

nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem 1rem;
  margin-top: 1.5rem;
}

nav a[aria-current="page"] {
  color: var(--green);
  font-weight: 700;
  text-decoration-thickness: 2px;
}

.meta {
  background: var(--surface);
  border-left: 4px solid var(--green);
  margin: 0 0 2.5rem;
  padding: 1rem 1.2rem;
}

section {
  border-top: 1px solid var(--rule);
  padding: 1.7rem 0 0.7rem;
}

h2 {
  font-size: 1.25rem;
  letter-spacing: -0.015em;
  margin: 0 0 0.65rem;
}

p,
li {
  color: var(--muted);
}

strong {
  color: var(--text);
}

code {
  background: var(--surface-soft);
  border-radius: 0.25rem;
  color: var(--text);
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  padding: 0.08rem 0.3rem;
}

footer {
  border-top: 1px solid var(--rule);
  color: var(--muted);
  margin-top: 2rem;
  padding-top: 1.5rem;
}

@media (max-width: 36rem) {
  .shell {
    padding-top: 1.25rem;
  }
}

@media (prefers-reduced-motion: no-preference) {
  a {
    transition: color 140ms ease;
  }
}