:root {
  --ink: #141a17;
  --paper: #f6f7f5;
  --accent: #1c7c68;
  --accent-ink: #f6f7f5;
  --line: #dce3de;
  --panel: #ffffff;
  /* Strong ease-out for UI entrances/exits (animate skill). Built-in CSS ease-out is too weak. */
  --ease-out: cubic-bezier(0.23, 1, 0.32, 1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --ink: #e8ede9;
    --paper: #0f1512;
    --accent: #35a085;
    --accent-ink: #0f1512;
    --line: #1c2622;
    --panel: #141b17;
  }
}

* {
  box-sizing: border-box;
}

html {
  color-scheme: light dark;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--accent) 45%, transparent);
  text-underline-offset: 3px;
}

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

.banner {
  background: var(--ink);
  color: var(--paper);
  text-align: center;
  font-size: 0.875rem;
  padding: 0.5rem 1rem;
}

.banner a {
  color: var(--paper);
  text-decoration-color: color-mix(in srgb, var(--paper) 55%, transparent);
}

header.site {
  max-width: 72rem;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.25rem 1.25rem 0.5rem;
}

.brand {
  font-weight: 600;
  font-size: 1.125rem;
  text-decoration: none;
  color: var(--ink);
}

nav.site {
  display: flex;
  gap: 1.25rem;
  flex-wrap: wrap;
  font-size: 0.9375rem;
}

nav.site a {
  text-decoration: none;
  color: var(--ink);
  opacity: 0.7;
}

nav.site a:hover,
nav.site a[aria-current="page"] {
  opacity: 1;
  color: var(--accent);
}

.nav-toggle {
  display: none;
  width: 2.25rem;
  height: 2.25rem;
  margin-left: auto;
  padding: 0;
  border: 0;
  background: none;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 1.25rem;
  height: 2px;
  margin: 0 auto;
  border-radius: 999px;
  background: var(--ink);
  transition: transform 150ms var(--ease-out), opacity 150ms var(--ease-out);
}

.nav-toggle span + span {
  margin-top: 4px;
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

@media (max-width: 640px) {
  .nav-toggle {
    display: block;
  }

  nav.site {
    display: none;
    position: absolute;
    inset-inline: 0;
    top: 100%;
    z-index: 10;
    flex-direction: column;
    gap: 0;
    padding: 0.5rem 1.25rem 1rem;
    background: var(--paper);
    border-bottom: 1px solid var(--line);
  }

  nav.site[data-open] {
    display: flex;
    animation: menu-in 200ms var(--ease-out) both;
  }

  nav.site a {
    padding: 0.625rem 0;
    border-top: 1px solid var(--line);
  }

  nav.site a:first-child {
    border-top: none;
  }

  header.site {
    position: relative;
  }
}

@keyframes menu-in {
  from {
    opacity: 0;
    transform: translateY(-8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (prefers-reduced-motion: reduce) {
  nav.site[data-open] {
    animation-duration: 1ms;
  }

  .nav-toggle span {
    transition-duration: 1ms;
  }
}

/* Hero entrance stagger (animate skill: rare/first-tier content, purpose = explanation). */
@keyframes reveal-up {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.reveal {
  animation: reveal-up 500ms var(--ease-out) both;
}

.reveal-1 {
  animation-delay: 80ms;
}

.reveal-2 {
  animation-delay: 160ms;
}

@media (prefers-reduced-motion: reduce) {
  .reveal {
    animation-duration: 1ms;
    animation-delay: 0ms;
  }
}

main {
  max-width: 72rem;
  margin: 0 auto;
  padding: 1.5rem 1.25rem 4rem;
}

.hero h1 {
  font-size: clamp(1.75rem, 1.2rem + 2vw, 2.75rem);
  line-height: 1.15;
  letter-spacing: -0.01em;
  margin: 0.5rem 0 0;
  max-width: 28ch;
}

.hero p.lede {
  font-size: 1.125rem;
  color: color-mix(in srgb, var(--ink) 70%, transparent);
  max-width: 46ch;
  margin-top: 0.75rem;
}

.cta-row {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-top: 1.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  border-radius: 999px;
  padding: 0.6rem 1.25rem;
  font-weight: 500;
  text-decoration: none;
  font-size: 0.9375rem;
}

.btn.primary {
  background: var(--accent);
  color: var(--accent-ink);
}

.btn.ghost {
  border: 1px solid var(--line);
  color: var(--ink);
}

.flow {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin: 2rem 0;
}

.flow .node {
  border: 1px solid var(--line);
  border-radius: 0.75rem;
  padding: 0.75rem 1rem;
  font-size: 0.9375rem;
  background: var(--panel);
}

.flow .node.emphasis {
  border-color: var(--accent);
  background: color-mix(in srgb, var(--accent) 10%, var(--panel));
}

.flow .arrow {
  color: color-mix(in srgb, var(--ink) 40%, transparent);
}

.repo-grid {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(2, 1fr);
  margin-top: 1.5rem;
}

@media (max-width: 640px) {
  .repo-grid {
    grid-template-columns: 1fr;
  }
}

.card {
  border: 1px solid var(--line);
  border-radius: 1rem;
  padding: 1.25rem;
  background: var(--panel);
}

.card h3 {
  margin: 0 0 0.25rem;
  font-size: 1.125rem;
}

.card p {
  margin: 0;
  color: color-mix(in srgb, var(--ink) 70%, transparent);
  font-size: 0.9375rem;
}

.card .meta {
  margin-top: 0.75rem;
  font-size: 0.8125rem;
  color: color-mix(in srgb, var(--ink) 55%, transparent);
}

section + section {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--line);
}

h2 {
  font-size: 1.5rem;
  letter-spacing: -0.01em;
}

dl.facts {
  display: grid;
  grid-template-columns: max-content 1fr;
  gap: 0.5rem 1.5rem;
  font-size: 0.9375rem;
}

dl.facts dt {
  color: color-mix(in srgb, var(--ink) 55%, transparent);
}

dl.facts dd {
  margin: 0;
}

code,
pre {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.875rem;
}

code {
  background: color-mix(in srgb, var(--ink) 8%, transparent);
  padding: 0.125rem 0.375rem;
  border-radius: 0.375rem;
}

pre {
  background: color-mix(in srgb, var(--ink) 6%, transparent);
  padding: 1rem;
  border-radius: 0.75rem;
  overflow-x: auto;
}

pre code {
  background: none;
  padding: 0;
}

ul.api-list {
  columns: 2;
  column-gap: 2rem;
  font-size: 0.9375rem;
  padding-left: 1.25rem;
}

@media (max-width: 640px) {
  ul.api-list {
    columns: 1;
  }
}

footer.site {
  max-width: 72rem;
  margin: 0 auto;
  padding: 2rem 1.25rem 3rem;
  border-top: 1px solid var(--line);
  font-size: 0.875rem;
  color: color-mix(in srgb, var(--ink) 60%, transparent);
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: space-between;
}