:root {
  --bg: #f4f5f2;
  --fg: #2b2d2a;
  --muted: #6f726c;
  --line: #dcded8;
  --surface: #ebece8;
  --code-bg: #e6e8e2;
  --accent: #b4541a;
  --accent-soft: #f9dfcc;
  --term-bg: #1f2220;
  --term-fg: #d9dcd6;
  --term-dim: #8a8e87;
  --term-prompt: #e9a46d;
  --term-warn: #f0c36b;
  --shadow: 0 1px 2px rgba(30, 30, 20, 0.04), 0 4px 14px rgba(30, 30, 20, 0.05);
  --code-str: #3f7050;
  --code-num: #8a5a00;
  --line-hl: rgba(180, 84, 26, 0.12);
  --diff-ins: #cfe6d3;
  --diff-del: #f5d8d4;
  --diff-ins-edge: #2e7d4f;
  --diff-del-edge: #c0392b;
  --font: -apple-system, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans CJK SC", system-ui, sans-serif;
  --kai: "LXGW WenKai Screen", "Kaiti SC", "STKaiti", "KaiTi", serif;
  --code-radius: 13px;
  --code-inset: 4px;
  --code-pad-x: 1.5rem;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, "Noto Sans Mono CJK SC", monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #1c1b19;
    --fg: #e4e1da;
    --muted: #9b978e;
    --line: #35332f;
    --surface: #26241f;
    --code-bg: #2d2b26;
    --accent: #e0834a;
    --accent-soft: #4a2e1c;
    --term-bg: #121311;
    --term-fg: #d9dcd6;
    --term-dim: #7d8078;
    --term-prompt: #e9a46d;
    --term-warn: #f0c36b;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 4px 14px rgba(0, 0, 0, 0.25);
    --code-str: #9cc49a;
    --code-num: #e0b566;
    --line-hl: rgba(224, 131, 74, 0.18);
    --diff-ins: #203f2a;
    --diff-del: #4b2724;
    --diff-ins-edge: #7fcf8f;
    --diff-del-edge: #f0796a;
  }
}

* {
  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: 1.85;
  overflow-x: hidden;
}

main {
  max-width: 60.5rem;
  margin: 0 auto;
  padding: 3rem 16px 5rem;
  counter-reset: section;
  animation: enter 0.4s ease-out both;
}

main.wide {
  max-width: 74rem;
}

@keyframes enter {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

h1,
h2,
h3 {
  font-family: var(--kai);
}

h1 {
  font-size: 2.625rem;
  line-height: 1.2;
  margin: 0.5rem 0 1rem;
  font-weight: 500;
  letter-spacing: -0.01em;
}

.lead {
  font-size: 1.1rem;
  line-height: 1.8;
  color: var(--muted);
  margin: 0 0 1.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--line);
}

.lead + * {
  margin-top: 3rem;
}

mark {
  color: var(--accent);
  font-weight: 700;
  background: linear-gradient(transparent 60%, var(--accent-soft) 60%);
}

h2 {
  font-size: 1.7rem;
  line-height: 1.3;
  margin: 3.5rem 0 0.75rem;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.index h2::before {
  content: none;
}

h2::before {
  counter-increment: section;
  content: counter(section, decimal-leading-zero);
  display: block;
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 400;
  letter-spacing: 0.1em;
  color: var(--muted);
  margin-bottom: 0.35rem;
}

h3 {
  font-size: 1.2rem;
  line-height: 1.4;
  margin: 2rem 0 0.6rem;
  font-weight: 700;
}

p,
ul,
ol {
  margin: 0 0 1.25rem;
}

ul,
ol {
  padding-left: 1.5rem;
}

li {
  margin-bottom: 0.35rem;
}

a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color 0.15s ease;
}

a:hover {
  border-bottom-color: var(--accent);
}

.nav {
  font-size: 0.9rem;
  color: var(--muted);
  margin-bottom: 2rem;
}

.page-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 2rem;
}

.page-head .nav {
  margin: 0;
}

.copy-page {
  display: inline-flex;
  align-items: center;
  gap: 0.45em;
  flex-shrink: 0;
  font-family: var(--mono);
  font-size: 0.75rem;
  line-height: 1;
  color: var(--muted);
  background: var(--bg);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.5em 0.8em;
  cursor: pointer;
}

.copy-page svg {
  width: 1.1em;
  height: 1.1em;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.3;
}

.copy-page:hover {
  color: var(--fg);
  border-color: var(--muted);
}

.copy-page.done {
  color: var(--accent);
}

.copy-page:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.tag:not(.token) {
  display: inline-block;
  font-family: var(--kai);
  font-size: 0.875rem;
  letter-spacing: 0.08em;
  line-height: 1.8;
  padding: 0 0.6rem;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  vertical-align: middle;
  margin-left: 0.75rem;
  font-weight: 500;
}

.hint {
  color: var(--muted);
  font-size: 0.875rem;
}

code {
  font-family: var(--mono);
  font-size: 0.875em;
  background: var(--code-bg);
  padding: 0.15em 0.4em;
  border-radius: 5px;
}

pre {
  font-family: var(--mono);
  font-size: 0.875rem;
  line-height: 1.7;
  background: var(--surface);
  padding: 1.25rem var(--code-pad-x);
  border-radius: var(--code-radius);
  overflow-x: auto;
  margin: 0 0 1.5rem;
}

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

blockquote {
  font-family: var(--kai);
  margin: 2.5rem 0;
  padding: 2rem 2.25rem;
  background: var(--surface);
  border-radius: 16px;
  font-size: 1.15rem;
  line-height: 1.7;
}

blockquote p {
  margin: 0;
}

blockquote footer {
  margin-top: 1rem;
  font-size: 0.9rem;
  color: var(--muted);
}

table {
  width: 100%;
  border-collapse: collapse;
  margin: 0 0 1.5rem;
  font-size: 0.9375rem;
  display: block;
  overflow-x: auto;
}

th,
td {
  text-align: left;
  vertical-align: top;
  padding: 0.6rem 0.8rem;
  border-bottom: 1px solid var(--line);
}

th {
  font-family: var(--mono);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  font-weight: 500;
  color: var(--muted);
  white-space: nowrap;
}

tr:last-child td {
  border-bottom: none;
}

.nb {
  white-space: nowrap;
}

.code-scroll {
  position: relative;
  border-radius: var(--code-radius);
  margin: 0 0 1.5rem;
}

.code-view {
  overflow-x: auto;
  border-radius: var(--code-radius);
}

.code-view pre {
  margin: 0;
  overflow: visible;
  width: max-content;
  min-width: 100%;
}

.code-view pre.wrapped {
  width: auto;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}

.code-bar {
  position: absolute;
  top: var(--code-inset);
  right: var(--code-inset);
  display: flex;
  align-items: stretch;
  height: calc((var(--code-radius) - var(--code-inset)) * 2);
  border-radius: calc(var(--code-radius) - var(--code-inset));
  background: var(--bg);
  border: 1px solid var(--line);
  font-family: var(--mono);
  font-size: 0.68rem;
  line-height: 1;
  color: var(--muted);
}

.code-lang {
  display: flex;
  align-items: center;
  padding: 0 0.7em;
}

.code-wrap {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  border-left: 1px solid var(--line);
  border-radius: 0 calc(var(--code-radius) - var(--code-inset)) calc(var(--code-radius) - var(--code-inset)) 0;
  padding: 0 0.7em;
  cursor: pointer;
}

.code-wrap:hover {
  color: var(--fg);
}

.code-wrap[aria-pressed="true"] {
  color: var(--accent);
}

.code-wrap:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: -2px;
}

@media (hover: hover) {
  .code-bar {
    opacity: 0;
    transition: opacity 0.12s ease;
  }
  .code-scroll:hover .code-bar,
  .code-scroll:focus-within .code-bar {
    opacity: 1;
  }
}

pre[data-line] {
  position: relative;
}

.line-highlight {
  position: absolute;
  left: 0;
  right: 0;
  margin-top: 1.25rem;
  background: var(--line-hl);
  border-left: 3px solid var(--accent);
  pointer-events: none;
  line-height: inherit;
  white-space: pre;
}

.diff-highlight .token.inserted:not(.prefix),
.diff-highlight .token.deleted:not(.prefix) {
  display: block;
  color: inherit;
  margin: 0 calc(var(--code-pad-x) * -1);
  padding: 0 var(--code-pad-x) 0 calc(var(--code-pad-x) - 3px);
  border-left: 3px solid;
}

.diff-highlight .token.inserted:not(.prefix) {
  background: var(--diff-ins);
  border-left-color: var(--diff-ins-edge);
}

.diff-highlight .token.deleted:not(.prefix) {
  background: var(--diff-del);
  border-left-color: var(--diff-del-edge);
}

.diff-highlight .token.prefix {
  font-weight: 700;
}

.diff-highlight .token.prefix.inserted {
  color: var(--diff-ins-edge);
}

.diff-highlight .token.prefix.deleted {
  color: var(--diff-del-edge);
}

.token.keyword,
.token.builtin,
.token.decorator,
.token.important {
  color: var(--accent);
}

.token.string,
.token.char,
.token.attr-value {
  color: var(--code-str);
}

.token.number,
.token.boolean,
.token.null,
.token.date {
  color: var(--code-num);
}

.token.comment,
.token.prolog,
.token.doctype {
  color: var(--muted);
  font-style: italic;
}

.token.function,
.token.class-name,
.token.tag {
  color: var(--fg);
  font-weight: 700;
}

.token.property,
.token.key,
.token.attr-name,
.token.operator,
.token.punctuation {
  color: var(--fg);
}

main mjx-container a[data-mjx-href],
main mjx-container a[data-mjx-href].mjx-visited {
  color: var(--accent);
}

mjx-container[display="true"] {
  overflow-x: auto;
  overflow-y: hidden;
  max-width: 100%;
  margin: 1rem 0;
}

.cards {
  list-style: none;
  padding: 0;
  margin: 0 0 1.5rem;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 18px;
}

.cards li {
  margin: 0;
}

.card {
  display: block;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  box-shadow: var(--shadow);
  overflow: hidden;
  color: inherit;
  transition: border-color 0.15s ease, transform 0.15s ease;
}

.card:hover,
.card:focus-visible {
  border-color: var(--accent);
  transform: translateY(-2px);
  outline: none;
}

.card-body {
  padding: 0.9rem 1.1rem 1.1rem;
}

.card strong {
  display: block;
  font-family: var(--kai);
  font-size: 1.0625rem;
  color: var(--accent);
  font-weight: 700;
  margin-bottom: 0.2rem;
}

.card-body span {
  display: block;
  color: var(--muted);
  font-size: 0.875rem;
  line-height: 1.6;
}

.card-tags {
  margin-top: 0.75rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.card-tags i {
  font-style: normal;
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  color: var(--muted);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0 0.5rem;
  line-height: 1.7;
}

.term {
  font-family: var(--mono);
  font-size: 0.875rem;
  line-height: 1.75;
  background: var(--term-bg);
  color: var(--term-fg);
  padding: 1.25rem 1.5rem;
  border-radius: 12px;
  overflow-x: auto;
  margin: 0 0 1.25rem;
  white-space: pre;
}

.term .prompt {
  color: var(--term-prompt);
}

.term .dim {
  color: var(--term-dim);
}

.term .warn {
  color: var(--term-warn);
}

.term .ref,
.callouts li::before {
  display: inline-block;
  min-width: 1.5em;
  text-align: center;
  background: var(--accent-soft);
  color: var(--accent);
  border-radius: 4px;
  font-family: var(--mono);
  font-size: 0.8rem;
  font-weight: 700;
  line-height: 1.7;
}

.term .ref {
  margin-left: 0.5em;
}

.callouts {
  counter-reset: callout;
  list-style: none;
  padding: 0;
}

.callouts li {
  counter-increment: callout;
  position: relative;
  padding-left: 2.4rem;
}

.callouts li::before {
  content: counter(callout);
  position: absolute;
  left: 0;
  top: 0.35em;
}

.wire-scroll {
  overflow-x: auto;
  margin: 0 0 1.5rem;
}

.wire {
  min-width: 640px;
  background: var(--surface);
  border-radius: 16px;
  padding: 1rem;
  display: grid;
  gap: 0.75rem;
  grid-template-columns: 12rem 1fr;
  grid-template-areas:
    "top top"
    "side body"
    "foot foot";
  font-size: 0.9rem;
  line-height: 1.6;
}

.wire > div {
  min-width: 0;
  border: 1.5px dashed var(--muted);
  border-radius: 10px;
  padding: 0.75rem 0.9rem;
  min-height: 3rem;
  color: var(--muted);
}

.wire > div > b {
  display: block;
  font-family: var(--mono);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  color: var(--accent);
  font-weight: 700;
  margin-bottom: 0.4rem;
}

.wire .top {
  grid-area: top;
}

.wire .side {
  grid-area: side;
  min-height: 13rem;
}

.wire .body {
  grid-area: body;
  min-height: 13rem;
}

.wire .foot {
  grid-area: foot;
}

.wire .rows {
  margin-bottom: 0.5rem;
}

.wire .row {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.25rem 0;
  border-bottom: 1px dotted var(--line);
}

.wire .bar {
  height: 0.65rem;
  background: var(--accent-soft);
  border-radius: 4px;
  margin: 0.35rem 0;
}

.wire.narrow {
  width: 360px;
  min-width: 0;
  grid-template-columns: 1fr;
  grid-template-areas:
    "top"
    "side"
    "body"
    "foot";
}

.wire.narrow .side,
.wire.narrow .body {
  min-height: auto;
}

.wire.narrow .rows {
  display: flex;
  gap: 0.5rem;
  overflow-x: auto;
  padding-bottom: 0.4rem;
}

.wire.narrow .row {
  flex: none;
  gap: 0.4rem;
  padding: 0.15rem 0.6rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  white-space: nowrap;
}

figure {
  margin: 0 0 2rem;
}

figure svg {
  width: 100%;
  height: auto;
  display: block;
}

figcaption {
  font-size: 0.875rem;
  color: var(--muted);
  margin-top: 0.75rem;
}

.diagram {
  font-family: var(--font);
  font-size: 13px;
}

.diagram rect {
  fill: var(--surface);
  stroke: var(--accent);
  stroke-width: 1.3;
}

.diagram text {
  fill: var(--fg);
}

.diagram .note {
  fill: var(--muted);
  font-family: var(--mono);
  font-size: 10px;
}

.diagram path,
.diagram line {
  stroke: var(--muted);
  stroke-width: 1.2;
  fill: none;
}

.diagram marker path {
  fill: var(--muted);
  stroke: none;
}

@media (max-width: 600px) {
  h1 {
    font-size: 2rem;
  }
  h2 {
    font-size: 1.45rem;
  }
}

.pv {
  aspect-ratio: 16 / 9;
  background: var(--code-bg);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
  padding: 14px 18px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
  font-family: var(--mono);
  font-size: 11px;
  line-height: 1.5;
  color: var(--muted);
}

.pv-a {
  animation-duration: 2s;
  animation-iteration-count: infinite;
  animation-timing-function: linear;
  animation-play-state: paused;
}

.card:hover .pv-a,
.card:focus-visible .pv-a {
  animation-play-state: running;
}

.pv-s1 {
  animation-name: pv-s1;
}

.pv-s2 {
  animation-name: pv-s2;
}

.pv-s3 {
  animation-name: pv-s3;
}

.pv-s4 {
  animation-name: pv-s4;
}

@keyframes pv-s1 {
  0% { opacity: 1; }
  3% { opacity: 0.15; }
  20% { opacity: 0.15; }
  26% { opacity: 1; }
  100% { opacity: 1; }
}

@keyframes pv-s2 {
  0% { opacity: 1; }
  3% { opacity: 0.15; }
  40% { opacity: 0.15; }
  46% { opacity: 1; }
  100% { opacity: 1; }
}

@keyframes pv-s3 {
  0% { opacity: 1; }
  3% { opacity: 0.15; }
  60% { opacity: 0.15; }
  66% { opacity: 1; }
  100% { opacity: 1; }
}

@keyframes pv-s4 {
  0% { opacity: 1; }
  3% { opacity: 0.15; }
  80% { opacity: 0.15; }
  86% { opacity: 1; }
  100% { opacity: 1; }
}

.pv-kit {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  width: 100%;
  flex: 1;
  min-height: 0;
}

.pv-kit > div {
  border-radius: 6px;
  padding: 7px 8px;
  min-height: 0;
}

.pv-kit i {
  display: block;
  height: 5px;
  width: 70%;
  margin: 4px 0;
  border-radius: 2px;
  background: var(--muted);
  opacity: 0.5;
}

.pv-kit i:nth-child(2) {
  width: 45%;
}

.pv-kit .k-quote {
  background: var(--surface);
  border-left: 3px solid var(--accent);
}

.pv-kit .k-code {
  background: var(--term-bg);
}

.pv-kit .k-code i {
  background: var(--term-dim);
}

.pv-kit .k-table i {
  width: 100%;
  height: 1px;
  margin: 7px 0;
}

.pv-kit .k-wire {
  border: 1.5px dashed var(--muted);
}

.pv-line {
  white-space: pre;
}

.pv-cmd {
  color: var(--fg);
}

.pv-chip {
  display: inline-block;
  font-size: 9px;
  line-height: 1.6;
  padding: 0 0.5em;
  border-radius: 999px;
  border: 1px solid var(--line);
  color: var(--muted);
}

.pv-chip.hot {
  border-color: var(--accent);
  background: var(--accent-soft);
  color: var(--accent);
}

.pv-cmd b {
  font-weight: 400;
  color: var(--accent);
  margin-right: 0.5em;
}

.pv-cmd span {
  display: inline-block;
  overflow: hidden;
  vertical-align: bottom;
  white-space: nowrap;
  animation-name: pv-type;
  animation-timing-function: steps(14, end);
}

@keyframes pv-type {
  0% { width: 100%; }
  3% { width: 0; }
  20% { width: 100%; }
  100% { width: 100%; }
}

.pv-dark {
  background: var(--term-bg);
  color: var(--term-dim);
}

.pv-dark .pv-cmd {
  color: var(--term-fg);
}

.pv-dark .pv-cmd b {
  color: var(--term-prompt);
}

.pv-svg {
  width: 100%;
  height: auto;
  display: block;
}

.pv-svg rect {
  fill: var(--surface);
  stroke: var(--accent);
  stroke-width: 1.5;
}

.pv-svg line {
  stroke: var(--muted);
  stroke-width: 1.5;
}

.pv-svg circle {
  fill: var(--accent);
  animation-name: pv-move;
  animation-timing-function: ease-in-out;
}

@keyframes pv-move {
  0% { transform: translateX(0); }
  85% { transform: translateX(96px); }
  100% { transform: translateX(96px); }
}

.pv-grid {
  display: grid;
  grid-template-columns: 1fr 2fr;
  grid-template-areas:
    "a a"
    "b c"
    "d d";
  gap: 5px;
  width: 100%;
  flex: 1;
  min-height: 0;
}

.pv-grid div {
  border: 1.5px dashed var(--muted);
  border-radius: 5px;
  padding: 2px 6px;
  color: var(--muted);
}

.pv-grid .a { grid-area: a; }
.pv-grid .b { grid-area: b; }
.pv-grid .c { grid-area: c; }
.pv-grid .d { grid-area: d; }

.pv-grid .pv-h1 { animation-name: pv-h1; }
.pv-grid .pv-h2 { animation-name: pv-h2; }
.pv-grid .pv-h3 { animation-name: pv-h3; }
.pv-grid .pv-h4 { animation-name: pv-h4; }

@keyframes pv-h1 {
  0%, 5% { background: transparent; border-color: var(--muted); }
  10%, 25% { background: var(--accent-soft); border-color: var(--accent); }
  30%, 100% { background: transparent; border-color: var(--muted); }
}

@keyframes pv-h2 {
  0%, 30% { background: transparent; border-color: var(--muted); }
  35%, 50% { background: var(--accent-soft); border-color: var(--accent); }
  55%, 100% { background: transparent; border-color: var(--muted); }
}

@keyframes pv-h3 {
  0%, 55% { background: transparent; border-color: var(--muted); }
  60%, 75% { background: var(--accent-soft); border-color: var(--accent); }
  80%, 100% { background: transparent; border-color: var(--muted); }
}

@keyframes pv-h4 {
  0%, 80% { background: transparent; border-color: var(--muted); }
  85%, 97% { background: var(--accent-soft); border-color: var(--accent); }
  100% { background: transparent; border-color: var(--muted); }
}

@media (prefers-reduced-motion: reduce) {
  main {
    animation: none;
  }
  .code-bar {
    transition: none;
  }
  a,
  .card {
    transition: none;
  }
  .card:hover,
  .card:focus-visible {
    transform: none;
  }
  .pv-a {
    animation: none;
  }
}