:root {
  color-scheme: light;
  --ink: #18212b;
  --muted: #556270;
  --paper: #f7f8fb;
  --surface: #ffffff;
  --line: #dce3ea;
  --extension: #5b80a5;
  --extension-dark: #3f658a;
  --extension-soft: #e9f1f8;
  --list: #ff8c1a;
  --list-dark: #d96f00;
  --shadow: 0 18px 45px rgba(28, 48, 68, 0.1);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.65;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 8% 0%, rgba(91, 128, 165, 0.13), transparent 28rem),
    var(--paper);
}

a {
  color: var(--extension-dark);
  text-underline-offset: 0.18em;
}

a:hover {
  text-decoration-thickness: 0.14em;
}

a:focus-visible {
  outline: 3px solid var(--extension);
  outline-offset: 3px;
  border-radius: 0.25rem;
}

code {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-size: 0.92em;
}

.site-header {
  position: sticky;
  z-index: 10;
  top: 0;
  border-bottom: 1px solid rgba(220, 227, 234, 0.9);
  background: rgba(247, 248, 251, 0.92);
  backdrop-filter: blur(16px);
}

.appbar,
main,
.site-footer {
  width: min(70rem, calc(100% - 2rem));
  margin-inline: auto;
}

.appbar {
  min-height: 4.25rem;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.7rem;
  color: var(--ink);
  font-weight: 760;
  text-decoration: none;
}

.brand-mark {
  width: 2rem;
  height: 2rem;
  display: grid;
  place-items: center;
  border-radius: 0.6rem;
  color: white;
  background: var(--extension);
  box-shadow: inset 0 -2px 0 rgba(0, 0, 0, 0.16);
  font-size: 0.75rem;
  letter-spacing: -0.08em;
}

.primary-nav {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-left: auto;
  font-size: 0.92rem;
}

.primary-nav a,
.github-link {
  color: var(--muted);
  text-decoration: none;
}

.primary-nav a:hover,
.github-link:hover {
  color: var(--ink);
}

.github-link {
  padding: 0.35rem 0.55rem;
  border-radius: 0.6rem;
  font-size: 0.84rem;
  font-weight: 760;
}

.language-switch {
  display: inline-flex;
  flex: 0 0 auto;
  padding: 0.2rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  white-space: nowrap;
}

.language-switch a {
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 760;
  text-decoration: none;
}

.language-switch a[aria-current="page"] {
  color: var(--ink);
  background: var(--extension-soft);
}

.hero {
  padding: clamp(4rem, 10vw, 7rem) 0 3.5rem;
  text-align: center;
}

.eyebrow {
  margin: 0 0 0.65rem;
  color: var(--extension-dark);
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  line-height: 1.18;
}

h1 {
  max-width: 13ch;
  margin: 0 auto;
  font-size: clamp(2.6rem, 8vw, 5.5rem);
  letter-spacing: -0.055em;
}

.lead {
  max-width: 41rem;
  margin: 1.25rem auto 0;
  color: var(--muted);
  font-size: clamp(1.05rem, 2vw, 1.25rem);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.8rem;
  margin-top: 1.8rem;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 3rem;
  padding: 0.55rem 1.1rem;
  border: 1px solid var(--line);
  border-radius: 0.75rem;
  color: var(--ink);
  background: var(--surface);
  font-weight: 700;
  text-decoration: none;
  box-shadow: 0 5px 16px rgba(28, 48, 68, 0.07);
}

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

.section {
  padding: 3.4rem 0;
}

.section-heading {
  max-width: 42rem;
  margin-bottom: 1.8rem;
}

.section-heading h2 {
  margin: 0;
  font-size: clamp(2rem, 5vw, 3.1rem);
  letter-spacing: -0.035em;
}

.section-heading p {
  margin: 0.75rem 0 0;
  color: var(--muted);
}

.quick-start,
.block-grid,
.notes-grid {
  display: grid;
  gap: 1rem;
}

.quick-start {
  grid-template-columns: repeat(3, 1fr);
  counter-reset: step;
}

.step,
.block-card,
.note-card {
  border: 1px solid var(--line);
  border-radius: 1rem;
  background: var(--surface);
  box-shadow: 0 8px 26px rgba(28, 48, 68, 0.06);
}

.step {
  position: relative;
  padding: 1.35rem;
  counter-increment: step;
}

.step::before {
  content: counter(step);
  width: 2rem;
  height: 2rem;
  display: grid;
  place-items: center;
  margin-bottom: 1rem;
  border-radius: 999px;
  color: white;
  background: var(--extension);
  font-weight: 800;
}

.step h3,
.block-card h3,
.note-card h3 {
  margin: 0;
}

.step p,
.block-card p,
.note-card p {
  margin: 0.55rem 0 0;
  color: var(--muted);
}

.diagram {
  overflow: hidden;
  margin: 0;
  border: 1px solid var(--line);
  border-radius: 1.25rem;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.diagram-input {
  padding: 1.5rem;
  border-bottom: 1px solid var(--line);
  background: #f2f5f8;
}

.diagram-label {
  display: block;
  margin-bottom: 0.45rem;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.text-sample {
  display: grid;
  gap: 0.28rem;
  max-width: 21rem;
  margin: 0;
  padding: 1rem;
  border: 1px solid #cfd7df;
  border-radius: 0.75rem;
  background: white;
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  line-height: 1.35;
  white-space: pre-line;
}

.diagram-path {
  display: grid;
  grid-template-columns: minmax(15rem, 1fr) 3rem minmax(12rem, 0.75fr);
  align-items: center;
  gap: 1rem;
  padding: 1.35rem 1.5rem;
  border-bottom: 1px solid var(--line);
}

.diagram-path:last-child {
  border-bottom: 0;
}

.arrow {
  color: var(--extension);
  font-size: 2rem;
  font-weight: 900;
  text-align: center;
}

.scratch-block {
  position: relative;
  padding: 0.72rem 1rem;
  border: 1px solid var(--extension-dark);
  border-radius: 0.65rem;
  color: white;
  background: var(--extension);
  font-weight: 680;
  box-shadow: inset 0 -3px 0 rgba(0, 0, 0, 0.14);
}

.scratch-block.reporter {
  border-radius: 999px;
}

.argument {
  display: inline-block;
  margin: 0 0.14rem;
  padding: 0.12rem 0.48rem;
  border-radius: 999px;
  color: var(--ink);
  background: white;
  font-weight: 600;
}

.result {
  padding: 0.85rem 1rem;
  border: 1px solid #bfd1e1;
  border-radius: 0.75rem;
  background: var(--extension-soft);
  font-weight: 760;
}

.list-result {
  border-color: #ffd3a3;
  background: #fff3e5;
}

.list-result ol {
  margin: 0.45rem 0 0;
  padding-left: 1.65rem;
  font-weight: 500;
}

.diagram figcaption {
  padding: 1rem 1.5rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  background: #fbfcfd;
  font-size: 0.92rem;
}

.block-grid {
  grid-template-columns: repeat(3, 1fr);
}

.block-card {
  overflow: hidden;
}

.block-card .scratch-block {
  margin: 1.25rem;
}

.block-copy {
  padding: 0 1.25rem 1.35rem;
}

.block-copy ul {
  margin: 0.85rem 0 0;
  padding-left: 1.2rem;
  color: var(--muted);
}

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

.note-card {
  padding: 1.35rem;
}

.callout {
  margin-top: 1rem;
  padding: 1rem 1.1rem;
  border-left: 0.3rem solid var(--list);
  border-radius: 0.35rem 0.75rem 0.75rem 0.35rem;
  background: #fff3e5;
}

.callout strong {
  color: #874500;
}

.site-footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  margin-top: 3rem;
  padding: 2rem 0 3rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.9rem;
}

.site-footer p {
  margin: 0;
}

@media (max-width: 48rem) {
  .quick-start,
  .block-grid,
  .notes-grid {
    grid-template-columns: 1fr;
  }

  .diagram-path {
    grid-template-columns: 1fr;
  }

  .arrow {
    transform: rotate(90deg);
  }

  .primary-nav {
    display: none;
  }

  .github-link {
    margin-left: auto;
  }

  .site-footer {
    flex-direction: column;
  }
}

@media (max-width: 34rem) {
  .brand-text {
    display: none;
  }
}

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