:root {
  --primary: #d00000;
  --primary-5: rgba(208, 0, 0, 0.05);
  --primary-10: rgba(208, 0, 0, 0.1);
  --primary-15: rgba(208, 0, 0, 0.15);
  --primary-50: rgba(208, 0, 0, 0.5);
  --bg: #ffffff;
  --fg: #111111;
  --muted: #4b5563;
  --subtle: #6b7280;
  --faint: #9ca3af;
  --border: #e5e7eb;
  --code-bg: rgba(208, 0, 0, 0.04);
  --font: "TikTok Sans", ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --primary: #ff5c5c;
    --primary-5: rgba(255, 92, 92, 0.07);
    --primary-10: rgba(255, 92, 92, 0.12);
    --primary-15: rgba(255, 92, 92, 0.18);
    --primary-50: rgba(255, 92, 92, 0.5);
    --bg: #111214;
    --fg: #ececec;
    --muted: #b4b8bf;
    --subtle: #9096a0;
    --faint: #6b7280;
    --border: #2a2d33;
    --code-bg: rgba(255, 92, 92, 0.06);
  }
}

* {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.5;
}

::selection {
  background: var(--primary-15);
}

a {
  color: inherit;
}

button {
  font: inherit;
  color: inherit;
}

button:not(:disabled) {
  cursor: pointer;
}

.wrap {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */

header.site {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 16px 24px;
  max-width: 1280px;
  margin: 0 auto;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-size: 22px;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.logo-mark {
  width: 30px;
  height: 30px;
  border-radius: 8px;
  background: var(--primary);
  color: #fff;
  display: grid;
  place-items: center;
  font-size: 18px;
  font-weight: 700;
}

.logo span.js {
  color: var(--primary);
}

nav.site {
  display: flex;
  align-items: center;
  gap: 24px;
}

nav.site a {
  text-decoration: none;
}

nav.site a:hover {
  color: var(--primary);
}

.pill {
  background: var(--primary-15);
  padding: 4px 16px;
  border-radius: 999px;
}

nav.site a.pill:hover {
  background: var(--primary-50);
  color: inherit;
}

/* Hero */

.hero {
  padding: 56px 0 64px;
  display: grid;
  grid-template-columns: 5fr 3fr;
  gap: 48px 48px;
  align-items: start;
}

.hero h1 {
  font-size: 36px;
  line-height: 1.2;
  font-weight: 400;
  margin: 32px 0 24px;
  max-width: 42rem;
  letter-spacing: -0.01em;
}

.hero .lede {
  font-size: 18px;
  line-height: 1.4;
  color: var(--muted);
  margin: 0 0 32px;
  max-width: 42rem;
}

.box {
  background: var(--primary-5);
  border-radius: 10px;
  padding: 16px;
}

.box h2 {
  font-size: 20px;
  font-weight: 500;
  margin: 0 0 6px;
}

.box p {
  margin: 0 0 16px;
  font-size: 14px;
  color: var(--subtle);
}

.linkish {
  background: none;
  border: 0;
  padding: 0;
  text-decoration: underline;
}

.linkish:disabled {
  text-decoration: none;
  color: var(--fg);
}

.install {
  background: var(--primary-5);
  border: 1px solid var(--primary);
  border-radius: 10px;
  padding: 8px 12px;
  font-family: var(--mono);
  font-size: 14px;
  white-space: pre-wrap;
  overflow-x: auto;
}

.install .prompt {
  color: var(--primary-50);
  user-select: none;
}

/* Live demo card */

.demo-card {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}

.demo-card .head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 10px;
  gap: 8px;
}

.demo-card h3 {
  margin: 0;
  font-size: 15px;
  font-weight: 500;
}

.tag {
  font-size: 12px;
  color: var(--subtle);
  white-space: nowrap;
}

.tag b {
  color: var(--primary);
  font-weight: 500;
}

canvas.field {
  width: 100%;
  aspect-ratio: 1;
  border-radius: 8px;
  display: block;
  background: var(--primary-5);
}

.stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin-top: 12px;
}

.stat {
  font-size: 12px;
  color: var(--subtle);
}

.stat b {
  display: block;
  font-size: 18px;
  font-weight: 500;
  color: var(--fg);
  font-variant-numeric: tabular-nums;
}

svg.spark {
  width: 100%;
  height: 48px;
  display: block;
  margin-top: 8px;
}

.demo-card .actions {
  display: flex;
  gap: 8px;
  margin-top: 12px;
}

.btn {
  border: 1px solid var(--primary);
  background: var(--primary-5);
  color: var(--fg);
  border-radius: 999px;
  padding: 4px 14px;
  font-size: 14px;
}

.btn:hover:not(:disabled) {
  background: var(--primary-15);
}

.btn:disabled {
  opacity: 0.5;
}

.btn.solid {
  background: var(--primary);
  color: #fff;
}

.btn.solid:hover:not(:disabled) {
  background: var(--primary);
  filter: brightness(1.1);
}

/* Sections */

section.block {
  padding: 48px 0;
}

section.block h2 {
  font-size: 20px;
  font-weight: 400;
  margin: 0 0 8px;
}

section.block .sub {
  margin: 0 0 16px;
  font-size: 14px;
  color: var(--subtle);
}

.explainer {
  background: var(--primary-5);
  border-radius: 14px;
  padding: 32px;
}

.explainer .inner {
  max-width: 44rem;
  margin: 0 auto;
}

.explainer h2 {
  text-align: center;
  font-size: 20px;
  font-weight: 500;
  margin: 0 0 24px;
}

.explainer ul {
  padding-left: 20px;
  margin: 0 0 24px;
}

.explainer li {
  margin-bottom: 8px;
}

.explainer li::marker {
  color: var(--faint);
}

/* Editor */

.editor {
  display: grid;
  grid-template-columns: 3fr 2fr;
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  min-height: 380px;
}

.editor textarea {
  border: 0;
  resize: none;
  padding: 16px;
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.6;
  background: var(--code-bg);
  color: var(--fg);
  outline: none;
  tab-size: 2;
  min-height: 380px;
  width: 100%;
}

.console {
  border-left: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.console .bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 12px;
  border-bottom: 1px solid var(--border);
  font-size: 13px;
  color: var(--subtle);
}

.console pre {
  margin: 0;
  padding: 12px;
  font-family: var(--mono);
  font-size: 12px;
  line-height: 1.55;
  white-space: pre-wrap;
  word-break: break-word;
  overflow: auto;
  flex: 1;
  max-height: 480px;
}

.console .err {
  color: var(--primary);
}

/* Cards */

.cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px 24px;
}

.card {
  background: var(--primary-5);
  border-radius: 10px;
  padding: 16px;
  text-decoration: none;
  transition: background 0.15s;
}

.card:hover {
  background: var(--primary-15);
}

.card h3 {
  font-size: 16px;
  font-weight: 400;
  margin: 0 0 8px;
}

.card h3::after {
  content: " ↗";
  color: var(--faint);
}

.card p {
  margin: 0;
  font-size: 14px;
  color: var(--subtle);
}

/* Layer grid */

.families {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px 32px;
}

.families h3 {
  font-size: 14px;
  font-weight: 500;
  margin: 0 0 4px;
}

.families p {
  margin: 0;
  font-size: 13px;
  color: var(--subtle);
  font-family: var(--mono);
  line-height: 1.7;
}

/* Code */

code,
pre {
  font-family: var(--mono);
}

pre.code {
  background: var(--code-bg);
  border-radius: 10px;
  padding: 16px;
  font-size: 13px;
  line-height: 1.6;
  overflow-x: auto;
  margin: 0;
}

footer.site {
  border-top: 1px solid var(--border);
  margin-top: 48px;
  padding: 24px;
  font-size: 13px;
  color: var(--subtle);
  text-align: center;
}

footer.site a {
  color: var(--subtle);
}

/* MNIST page */

.mnist {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  padding: 24px 0 48px;
}

.panel {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
}

.panel h2 {
  font-size: 18px;
  font-weight: 500;
  margin: 0 0 6px;
}

.panel p.sub {
  margin: 0 0 16px;
  font-size: 14px;
  color: var(--subtle);
}

.log {
  font-family: var(--mono);
  font-size: 12px;
  background: var(--code-bg);
  border-radius: 8px;
  padding: 10px 12px;
  height: 180px;
  overflow: auto;
  white-space: pre-wrap;
  margin-top: 12px;
}

.draw-row {
  display: flex;
  gap: 20px;
  align-items: flex-start;
  flex-wrap: wrap;
}

canvas.pad {
  width: 224px;
  height: 224px;
  border-radius: 10px;
  background: #000;
  touch-action: none;
  cursor: crosshair;
}

.bars {
  flex: 1;
  min-width: 180px;
  display: grid;
  gap: 4px;
}

.bar-row {
  display: grid;
  grid-template-columns: 16px 1fr 44px;
  gap: 8px;
  align-items: center;
  font-size: 13px;
  font-variant-numeric: tabular-nums;
}

.bar-track {
  height: 10px;
  background: var(--primary-5);
  border-radius: 5px;
  overflow: hidden;
}

.bar-fill {
  height: 100%;
  background: var(--primary);
  width: 0;
  transition: width 0.15s;
}

.controls {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  align-items: center;
}

select {
  font: inherit;
  font-size: 14px;
  padding: 4px 8px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--fg);
}

/* Examples page */

.page-title {
  font-weight: 400;
  font-size: 30px;
  margin: 24px 0 8px;
}

.page-lede {
  color: var(--muted);
  margin: 0;
  max-width: 46rem;
}

.page-lede a {
  color: var(--primary);
}

.ex-tabs {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 12px;
  margin: 24px 0 0;
}

.ex-tab {
  text-align: left;
  border: 1px solid transparent;
  background: var(--primary-5);
  border-radius: 10px;
  padding: 12px 14px;
  display: flex;
  flex-direction: column;
  gap: 2px;
  transition: background 0.15s;
}

.ex-tab:hover {
  background: var(--primary-10);
}

.ex-tab[aria-selected="true"] {
  border-color: var(--primary);
  background: var(--primary-10);
}

.ex-tabs.busy .ex-tab:not([aria-selected="true"]) {
  opacity: 0.5;
  cursor: not-allowed;
}

.ex-tab span {
  font-size: 12px;
  color: var(--primary);
}

.ex-tab b {
  font-weight: 500;
  font-size: 15px;
  line-height: 1.3;
}

.ex-tab small {
  font-size: 12px;
  color: var(--subtle);
  line-height: 1.4;
}

.ex {
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  gap: 24px;
  padding: 24px 0 48px;
  align-items: start;
}

.ex-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 13px;
  margin-bottom: 8px;
}

.ex-head a,
.ex-code-head a {
  color: var(--subtle);
  text-decoration: none;
}

.ex-head a:hover,
.ex-code-head a:hover {
  color: var(--primary);
}

.ex-note {
  border-left: 2px solid var(--primary);
  padding-left: 10px;
}

.progress {
  height: 4px;
  border-radius: 2px;
  background: var(--primary-5);
  margin: 16px 0 12px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  width: 0;
  background: var(--primary);
  transition: width 0.2s;
}

svg.chart {
  width: 100%;
  height: 120px;
  margin-top: 12px;
  background: var(--primary-5);
  border-radius: 8px;
}

.chart-legend {
  display: flex;
  gap: 16px;
  font-size: 12px;
  color: var(--subtle);
  font-family: var(--mono);
  min-height: 18px;
  margin-top: 4px;
}

.chart-legend i {
  display: inline-block;
  width: 10px;
  height: 2px;
  margin-right: 6px;
  vertical-align: middle;
}

.log.ex-log {
  height: 320px;
  margin: 8px 0 0;
}

.try {
  margin-top: 20px;
}

.try-row {
  display: flex;
  gap: 8px;
}

.try-row input {
  flex: 1;
  min-width: 0;
  font: inherit;
  font-size: 14px;
  padding: 6px 10px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--fg);
}

.try-out {
  font-family: var(--mono);
  font-size: 14px;
  min-height: 21px;
  margin: 10px 0 0;
}

.ex-code-head {
  display: flex;
  justify-content: space-between;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--subtle);
  margin-bottom: 8px;
}

.ex-code pre.code {
  font-size: 12px;
  max-height: 900px;
  overflow: auto;
}

/* Manual */

.manual {
  display: grid;
  grid-template-columns: 240px minmax(0, 1fr);
  gap: 48px;
  padding: 24px 0 48px;
}

.manual aside {
  position: sticky;
  top: 16px;
  align-self: start;
  max-height: calc(100vh - 32px);
  overflow: auto;
  font-size: 14px;
}

.manual aside a {
  display: block;
  text-decoration: none;
  padding: 3px 0;
  color: var(--muted);
}

.manual aside a.h3 {
  padding-left: 12px;
  font-size: 13px;
  color: var(--subtle);
}

.manual aside a:hover {
  color: var(--primary);
}

.prose {
  max-width: 48rem;
}

.prose h1 {
  font-size: 32px;
  font-weight: 400;
  margin: 0 0 16px;
}

.prose h2 {
  font-size: 22px;
  font-weight: 500;
  margin: 48px 0 12px;
  padding-top: 8px;
}

.prose h3 {
  font-size: 17px;
  font-weight: 500;
  margin: 28px 0 8px;
}

.prose p,
.prose li {
  color: var(--fg);
}

.prose a {
  color: var(--primary);
}

.prose code {
  background: var(--code-bg);
  border-radius: 4px;
  padding: 1px 5px;
  font-size: 0.88em;
}

.prose pre {
  background: var(--code-bg);
  border-radius: 10px;
  padding: 14px 16px;
  overflow-x: auto;
  font-size: 13px;
  line-height: 1.6;
}

.prose pre code {
  background: none;
  padding: 0;
  font-size: inherit;
}

.prose table {
  border-collapse: collapse;
  width: 100%;
  font-size: 14px;
  margin: 16px 0;
  display: block;
  overflow-x: auto;
}

.prose th,
.prose td {
  border-bottom: 1px solid var(--border);
  padding: 6px 10px;
  text-align: left;
  vertical-align: top;
}

.prose th {
  font-weight: 500;
}

.prose blockquote {
  margin: 16px 0;
  padding: 8px 16px;
  border-left: 3px solid var(--primary);
  background: var(--primary-5);
  border-radius: 0 8px 8px 0;
}

/* Responsive */

@media (max-width: 900px) {
  .hero,
  .editor,
  .mnist,
  .ex,
  .manual {
    grid-template-columns: 1fr;
  }
  .hero h1 {
    margin-top: 0;
  }
  .console {
    border-left: 0;
    border-top: 1px solid var(--border);
  }
  .cards {
    grid-template-columns: 1fr 1fr;
  }
  .families,
  .ex-tabs {
    grid-template-columns: 1fr 1fr;
  }
  .manual aside {
    position: static;
    max-height: none;
  }
}

@media (max-width: 600px) {
  .wrap,
  header.site {
    padding-left: 16px;
    padding-right: 16px;
  }
  .hero {
    padding-top: 24px;
  }
  .hero h1 {
    font-size: 28px;
  }
  .cards,
  .families,
  .ex-tabs {
    grid-template-columns: 1fr;
  }
  nav.site {
    gap: 14px;
    font-size: 15px;
  }
  nav.site .wide {
    display: none;
  }
  .explainer {
    padding: 24px 18px;
  }
}