:root {
  color-scheme: light dark;
  --bg: #f6f8fa;
  --surface: #ffffff;
  --surface-muted: #eef1f4;
  --text: #18212b;
  --muted: #59636e;
  --line: #d0d7de;
  --accent: #087a54;
  --accent-strong: #065f46;
  --accent-soft: #dff5ea;
  --code-bg: #101820;
  --code-text: #d8e4df;
  --shadow: 0 24px 70px rgb(31 45 38 / 12%);
  --radius: 14px;
  --max-width: 1180px;
  font-family:
    ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-synthesis: none;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1117;
    --surface: #151b23;
    --surface-muted: #1b232d;
    --text: #f0f3f6;
    --muted: #a7b0ba;
    --line: #303a46;
    --accent: #56c596;
    --accent-strong: #72d6aa;
    --accent-soft: #163b2f;
    --code-bg: #080c10;
    --code-text: #d8e4df;
    --shadow: 0 24px 70px rgb(0 0 0 / 32%);
  }
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-size: 16px;
  line-height: 1.6;
  text-rendering: optimizeLegibility;
}

a {
  color: inherit;
  text-decoration-color: var(--accent);
  text-underline-offset: 0.22em;
}

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

code,
pre {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}

pre {
  margin: 0;
  overflow-x: auto;
}

.skip-link {
  position: fixed;
  top: 1rem;
  left: 1rem;
  z-index: 10;
  transform: translateY(-160%);
  padding: 0.65rem 0.9rem;
  border-radius: 8px;
  background: var(--text);
  color: var(--bg);
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header,
main,
footer {
  width: min(calc(100% - 40px), var(--max-width));
  margin-inline: auto;
}

.site-header {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  border-bottom: 1px solid var(--line);
}

.wordmark {
  font-size: 1.05rem;
  font-weight: 780;
  letter-spacing: -0.03em;
  text-decoration: none;
}

nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  white-space: nowrap;
}

nav a {
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 650;
  text-decoration: none;
}

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

nav .nav-cta {
  padding: 0.42rem 0.78rem;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--text);
}

.hero {
  min-height: calc(100dvh - 73px);
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(360px, 0.95fr);
  align-items: center;
  gap: clamp(3rem, 7vw, 7rem);
  padding-block: clamp(4rem, 9vh, 6rem);
}

.eyebrow {
  margin: 0 0 1rem;
  color: var(--accent);
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: 0.76rem;
  font-weight: 760;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 14ch;
  margin-bottom: 1.35rem;
  font-size: clamp(3.4rem, 5.4vw, 4.9rem);
  font-weight: 780;
  letter-spacing: -0.075em;
  line-height: 0.92;
}

.lede {
  max-width: 50ch;
  margin-bottom: 2rem;
  color: var(--muted);
  font-size: clamp(1.05rem, 1.7vw, 1.25rem);
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
}

.button {
  min-height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.7rem 1rem;
  border: 1px solid var(--line);
  border-radius: 9px;
  font-weight: 720;
  line-height: 1;
  text-decoration: none;
  transition:
    transform 140ms ease,
    border-color 140ms ease,
    background 140ms ease;
}

.button:hover {
  transform: translateY(-1px);
}

.button:active {
  transform: translateY(1px);
}

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

@media (prefers-color-scheme: dark) {
  .button.primary {
    color: #08110d;
  }
}

.button.secondary:hover {
  border-color: var(--accent);
  background: var(--accent-soft);
}

.result-preview {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.result-preview figcaption {
  padding: 0.8rem 1rem;
  border-bottom: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 700;
}

.result-preview pre {
  min-height: 410px;
  padding: clamp(1.1rem, 3vw, 2rem);
  background: var(--code-bg);
  color: var(--code-text);
  font-size: clamp(0.76rem, 1.15vw, 0.92rem);
  line-height: 1.75;
}

.source-rail {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  border-block: 1px solid var(--line);
}

.source-rail span {
  padding: 1rem 0.75rem;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 760;
  text-align: center;
}

.source-rail span + span {
  border-left: 1px solid var(--line);
}

.capabilities,
.interfaces,
.quickstart,
.principles,
.closing {
  padding-block: clamp(5rem, 11vw, 9rem);
}

.section-intro {
  max-width: 700px;
  margin-bottom: 3.5rem;
}

h2 {
  margin-bottom: 1rem;
  font-size: clamp(2.35rem, 5vw, 4.5rem);
  font-weight: 760;
  letter-spacing: -0.055em;
  line-height: 1;
}

.section-intro p,
.principles-copy p,
.quickstart p,
.closing p {
  color: var(--muted);
  font-size: 1.05rem;
}

.capability-grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 1rem;
}

.capability {
  grid-column: span 5;
  min-height: 230px;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  padding: clamp(1.4rem, 3vw, 2.2rem);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}

.capability-wide {
  grid-column: span 7;
}

.capability-accent {
  background: var(--accent-soft);
}

.capability h3 {
  margin-bottom: 0.65rem;
  font-size: 1.45rem;
  letter-spacing: -0.025em;
}

.capability p {
  max-width: 43ch;
  color: var(--muted);
}

.capability code {
  margin-top: auto;
  padding: 0.35rem 0.52rem;
  border-radius: 7px;
  background: var(--surface-muted);
  color: var(--accent-strong);
  font-size: 0.78rem;
  font-weight: 700;
}

.interfaces {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: clamp(3rem, 9vw, 9rem);
  border-top: 1px solid var(--line);
}

.interface-list article {
  display: grid;
  grid-template-columns: 130px 1fr;
  gap: 1.5rem;
  padding-block: 1.5rem;
  border-bottom: 1px solid var(--line);
}

.interface-list article:first-child {
  border-top: 1px solid var(--line);
}

.interface-name {
  font-weight: 780;
}

.interface-list p {
  margin: 0;
  color: var(--muted);
}

.interface-list code {
  font-size: 0.82em;
}

.quickstart {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  align-items: center;
  gap: clamp(3rem, 8vw, 7rem);
  border-block: 1px solid var(--line);
}

.quickstart pre {
  padding: 1.5rem;
  border-radius: var(--radius);
  background: var(--code-bg);
  color: var(--code-text);
  font-size: 0.8rem;
  line-height: 1.8;
}

.principles {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: clamp(3rem, 10vw, 9rem);
}

.principles-copy a {
  color: var(--accent-strong);
  font-weight: 720;
}

dl {
  margin: 0;
}

dl div {
  padding-block: 1.2rem;
  border-bottom: 1px solid var(--line);
}

dl div:first-child {
  border-top: 1px solid var(--line);
}

dt {
  margin-bottom: 0.25rem;
  font-weight: 780;
}

dd {
  margin: 0;
  color: var(--muted);
}

.closing {
  max-width: 790px;
  margin-inline: 0 auto;
}

.closing p {
  margin-bottom: 1.7rem;
}

footer {
  min-height: 96px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.86rem;
}

footer > span {
  color: var(--text);
  font-weight: 780;
}

footer div {
  display: flex;
  gap: 1.2rem;
}

@media (max-width: 780px) {
  .site-header {
    min-height: 64px;
  }

  nav a:not(.nav-cta) {
    display: none;
  }

  .hero,
  .interfaces,
  .quickstart,
  .principles {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
    gap: 3rem;
    padding-block: 4.5rem;
  }

  h1 {
    max-width: 10ch;
    font-size: clamp(3.2rem, 17vw, 5.4rem);
  }

  .result-preview pre {
    min-height: 0;
  }

  .source-rail {
    grid-template-columns: repeat(2, 1fr);
  }

  .source-rail span {
    border-bottom: 1px solid var(--line);
  }

  .source-rail span + span {
    border-left: 0;
  }

  .source-rail span:nth-child(even) {
    border-left: 1px solid var(--line);
  }

  .source-rail span:last-child {
    grid-column: 1 / -1;
  }

  .capability,
  .capability-wide {
    grid-column: 1 / -1;
  }

  .interface-list article {
    grid-template-columns: 95px 1fr;
  }

  footer {
    align-items: flex-start;
    flex-direction: column;
    justify-content: center;
    padding-block: 1.5rem;
  }

  footer div {
    flex-wrap: wrap;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
  }
}