:root {
  --ink: var(--color-text);
  --muted: var(--color-text-muted);
  --paper: var(--color-bg);
  --panel: var(--color-surface);
  --panel-strong: var(--color-surface-raised);
  --line: var(--color-border);
  --acid: var(--color-accent);
  --mint: var(--color-interactive);
  --cyan: var(--color-accent);
  --serif: var(--font-display);
  --sans: var(--font-body);
  --mono: var(--font-mono);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 12% 6%, rgba(var(--color-interactive-rgb), 0.09), transparent 25rem),
    linear-gradient(rgba(var(--color-accent-rgb), 0.025) 1px, transparent 1px),
    var(--paper);
  background-size: auto, 100% 4rem, auto;
  font-family: var(--sans);
  line-height: 1.7;
}

a {
  color: inherit;
  text-decoration: none;
}

button,
input {
  font: inherit;
}

[hidden] {
  display: none !important;
}

.knowledge-shell {
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
}

.knowledge-header {
  position: sticky;
  z-index: 20;
  top: 0;
  border-bottom: 1px solid var(--line);
  background: rgba(7, 17, 14, 0.88);
  backdrop-filter: blur(18px);
}

.knowledge-nav {
  min-height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.knowledge-brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-family: var(--mono);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.14em;
}

.knowledge-brand-mark {
  width: 31px;
  height: 31px;
  display: grid;
  place-items: center;
  border: 1px solid var(--acid);
  border-radius: 50%;
  color: var(--acid);
}

.knowledge-nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
  color: var(--muted);
  font-size: 14px;
}

.knowledge-nav-links a:hover,
.article-body a:hover,
.toc a:hover {
  color: var(--acid);
}

.library-hero,
.article-hero {
  padding: clamp(72px, 10vw, 132px) 0 54px;
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 18px;
  color: var(--acid);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.eyebrow::before {
  content: "";
  width: 34px;
  height: 1px;
  background: var(--acid);
}

.library-hero h1,
.article-hero h1 {
  max-width: 920px;
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(46px, 8vw, 94px);
  font-weight: 500;
  line-height: 1.02;
  letter-spacing: -0.04em;
}

.article-hero h1 {
  font-size: clamp(42px, 6vw, 74px);
}

.hero-copy {
  max-width: 760px;
  margin: 25px 0 0;
  color: var(--muted);
  font-size: clamp(16px, 2vw, 19px);
}

.library-search {
  margin-top: 38px;
  max-width: 680px;
  position: relative;
}

.library-search::before {
  content: "/";
  position: absolute;
  left: 20px;
  top: 50%;
  color: var(--acid);
  font-family: var(--mono);
  transform: translateY(-50%);
}

.library-search input {
  width: 100%;
  padding: 16px 20px 16px 44px;
  border: 1px solid var(--line);
  border-radius: 8px;
  outline: none;
  color: var(--ink);
  background: rgba(13, 21, 32, 0.9);
}

.library-search input:focus {
  border-color: rgba(var(--color-accent-rgb), 0.65);
  box-shadow: 0 0 0 3px rgba(var(--color-accent-rgb), 0.08);
}

.section {
  padding: 0 0 72px;
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 22px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}

.section-heading h2 {
  margin: 0;
  font-family: var(--serif);
  font-size: 32px;
  font-weight: 500;
}

.section-heading span {
  color: var(--muted);
  font-family: var(--mono);
  font-size: 12px;
}

.category-grid,
.article-grid,
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.category-card,
.article-card,
.feature-card {
  min-height: 180px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(13, 21, 32, 0.68);
  transition: border-color 180ms ease, transform 180ms ease, background 180ms ease;
}

.category-card:hover,
.article-card:hover,
.feature-card:hover {
  border-color: rgba(var(--color-accent-rgb), 0.46);
  background: var(--panel-strong);
  transform: translateY(-3px);
}

.category-card small,
.article-card small,
.feature-card small {
  color: var(--acid);
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.category-card h3,
.article-card h3,
.feature-card h3 {
  margin: 24px 0 8px;
  font-family: var(--serif);
  font-size: 24px;
  font-weight: 500;
  line-height: 1.3;
}

.article-card p,
.feature-card p {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
}

.card-arrow {
  margin-top: 22px;
  color: var(--mint);
  font-family: var(--mono);
  font-size: 12px;
}

.feature-card {
  min-height: 220px;
  background:
    linear-gradient(135deg, rgba(var(--color-interactive-rgb), 0.12), transparent 55%),
    var(--panel);
}

.feature-card:nth-child(3n + 2) {
  background:
    linear-gradient(135deg, rgba(var(--color-accent-rgb), 0.12), transparent 55%),
    var(--panel);
}

.feature-card:nth-child(3n) {
  background:
    linear-gradient(135deg, rgba(255, 189, 107, 0.1), transparent 55%),
    var(--panel);
}

.search-empty {
  padding: 40px;
  border: 1px dashed var(--line);
  color: var(--muted);
  text-align: center;
}

.article-layout {
  display: grid;
  grid-template-columns: 230px minmax(0, 760px);
  justify-content: space-between;
  gap: clamp(44px, 8vw, 112px);
  padding-bottom: 100px;
}

.article-rail {
  position: sticky;
  top: 92px;
  align-self: start;
  display: grid;
  gap: 22px;
  max-height: calc(100vh - 112px);
  overflow: auto;
  padding-right: 6px;
  scrollbar-width: thin;
  scrollbar-color: var(--line) transparent;
}

.toc {
  position: static;
  max-height: none;
  overflow: visible;
}

.toc strong {
  display: block;
  margin-bottom: 14px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.12em;
}

.toc a {
  display: block;
  margin: 8px 0;
  padding-left: 12px;
  border-left: 1px solid var(--line);
  color: var(--color-text-dim);
  font-size: 13px;
  line-height: 1.45;
}

.toc a.sub {
  padding-left: 24px;
}

.toc a.active {
  border-color: var(--acid);
  color: var(--acid);
}

.article-body {
  min-width: 0;
  font-size: 17px;
}

.article-body h2,
.article-body h3,
.article-body h4 {
  scroll-margin-top: 104px;
  font-family: var(--serif);
  font-weight: 500;
  line-height: 1.3;
}

.article-body h2 {
  margin: 64px 0 20px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line);
  font-size: 34px;
}

.article-body h3 {
  margin: 42px 0 16px;
  color: var(--color-text);
  font-size: 25px;
}

.article-body h4 {
  margin: 32px 0 12px;
  font-size: 20px;
}

.article-body p {
  margin: 0 0 20px;
  color: var(--color-text-muted);
}

.article-body strong {
  color: var(--ink);
}

.article-body a {
  color: var(--mint);
  text-decoration: underline;
  text-decoration-color: rgba(var(--color-interactive-rgb), 0.35);
  text-underline-offset: 3px;
}

.article-body ul,
.article-body ol {
  margin: 0 0 24px;
  padding-left: 24px;
  color: var(--color-text-muted);
}

.article-body li {
  margin: 7px 0;
  padding-left: 4px;
}

.article-body li::marker {
  color: var(--acid);
}

.article-body code {
  padding: 0.15em 0.42em;
  border: 1px solid var(--line);
  border-radius: 4px;
  color: #d9f99d;
  background: rgba(var(--color-accent-rgb), 0.06);
  font-family: var(--mono);
  font-size: 0.88em;
}

.article-body pre {
  max-width: 100%;
  margin: 26px 0;
  padding: 22px;
  overflow-x: auto;
  overflow-y: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #050b09;
  box-shadow: inset 3px 0 var(--mint);
  tab-size: 4;
}

.article-body pre code {
  padding: 0;
  border: 0;
  color: #cbd8d1;
  background: none;
  font-size: 13px;
  line-height: 1.75;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
}

.article-body table {
  width: 100%;
  margin: 28px 0;
  border-collapse: collapse;
  font-size: 14px;
}

.article-body th,
.article-body td {
  padding: 12px 14px;
  border: 1px solid var(--line);
  text-align: left;
}

.article-body th {
  color: var(--acid);
  background: var(--panel);
}

.article-body hr {
  margin: 48px 0;
  border: 0;
  border-top: 1px solid var(--line);
}

.article-callout {
  margin: 38px 0;
  padding: 22px;
  border: 1px solid rgba(var(--color-accent-rgb), 0.32);
  border-radius: 8px;
  background: rgba(var(--color-accent-rgb), 0.055);
}

.article-callout strong {
  display: block;
  margin-bottom: 5px;
  color: var(--acid);
}

.article-pager {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-top: 70px;
}

.article-pager a {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 8px;
  text-decoration: none;
}

.article-pager a:last-child {
  text-align: right;
}

.article-pager a:hover {
  border-color: rgba(var(--color-accent-rgb), 0.45);
  background: var(--panel);
}

.article-pager small {
  display: block;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 10px;
}

.knowledge-footer {
  padding: 32px 0 52px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-family: var(--mono);
  font-size: 11px;
}

@media (max-width: 900px) {
  .category-grid,
  .article-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .feature-grid {
    grid-template-columns: 1fr 1fr;
  }

  .article-layout {
    grid-template-columns: 1fr;
  }

  .article-rail {
    display: contents;
  }

  .article-rail .toc {
    grid-row: 1;
  }

  .article-body {
    grid-row: 2;
  }

  .article-rail .article-progress-card {
    grid-row: 3;
  }

  .toc {
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 8px;
  }
}

@media (max-width: 620px) {
  .knowledge-shell {
    width: min(100% - 24px, 1180px);
  }

  .knowledge-nav-links a:first-child {
    display: none;
  }

  .category-grid,
  .article-grid,
  .feature-grid,
  .article-pager {
    grid-template-columns: 1fr;
  }

  .library-hero,
  .article-hero {
    padding-top: 56px;
  }

  .article-body {
    font-size: 16px;
  }

  .article-body h2 {
    font-size: 29px;
  }

  .article-pager a:last-child {
    text-align: left;
  }
}
.dynamic-deck {
  margin: 0 0 72px;
  overflow: hidden;
  border: 1px solid rgba(var(--color-accent-rgb), 0.28);
  border-radius: 10px;
  background:
    radial-gradient(circle at 82% 0%, rgba(var(--color-accent-rgb), 0.1), transparent 24rem),
    linear-gradient(145deg, rgba(var(--color-accent-rgb), 0.055), transparent 42%),
    var(--color-bg);
  box-shadow: 0 28px 80px rgba(0, 0, 0, 0.24);
}

.deck-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  padding: 24px 26px 22px;
  border-bottom: 1px solid var(--line);
}

.deck-kicker,
.deck-step-meta {
  color: var(--acid);
  font-family: var(--mono);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.12em;
}

.article-body .deck-header h2 {
  margin: 7px 0 0;
  padding: 0;
  border: 0;
  font-family: var(--sans);
  font-size: 20px;
  font-weight: 650;
  letter-spacing: -0.02em;
}

.deck-counter {
  flex: 0 0 auto;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 13px;
}

.deck-counter b {
  color: var(--acid);
  font-size: 28px;
  font-weight: 500;
}

.deck-stage {
  display: grid;
  grid-template-columns: 190px minmax(0, 1fr);
  min-height: 420px;
}

.deck-nav {
  max-height: 520px;
  overflow: auto;
  border-right: 1px solid var(--line);
  scrollbar-color: rgba(var(--color-accent-rgb), 0.3) transparent;
}

.deck-nav button {
  width: 100%;
  display: grid;
  grid-template-columns: 30px 1fr;
  gap: 8px;
  padding: 13px 14px;
  border: 0;
  border-bottom: 1px solid rgba(var(--color-border-rgb), 0.08);
  color: #84948b;
  background: transparent;
  text-align: left;
  cursor: pointer;
  transition: color 180ms ease, background 180ms ease;
}

.deck-nav button:hover {
  color: var(--ink);
  background: rgba(var(--color-interactive-rgb), 0.055);
}

.deck-nav button.active {
  color: var(--ink);
  background: linear-gradient(90deg, rgba(var(--color-accent-rgb), 0.13), transparent);
  box-shadow: inset 2px 0 var(--acid);
}

.deck-nav button span {
  color: var(--acid);
  font-family: var(--mono);
  font-size: 10px;
}

.deck-nav button strong {
  font-size: 12px;
  font-weight: 500;
  line-height: 1.45;
}

.deck-slides {
  min-width: 0;
  position: relative;
}

.deck-slide {
  min-height: 420px;
  padding: 34px clamp(24px, 5vw, 48px);
  animation: deck-in 400ms cubic-bezier(0.2, 0.75, 0.25, 1) both;
}

.article-body .deck-slide h3 {
  margin: 12px 0 20px;
  font-size: clamp(28px, 4vw, 39px);
}

.article-body .deck-slide p {
  color: #d2ddd7;
  font-size: 16px;
}

.article-body .deck-slide ul,
.article-body .deck-slide ol {
  display: grid;
  gap: 8px;
  margin: 22px 0;
  padding: 0;
  list-style: none;
}

.article-body .deck-slide li {
  margin: 0;
  padding: 10px 12px 10px 34px;
  position: relative;
  border: 1px solid rgba(var(--color-border-rgb), 0.1);
  border-radius: 5px;
  background: rgba(255, 255, 255, 0.018);
  font-size: 14px;
}

.article-body .deck-slide li::before {
  content: "→";
  position: absolute;
  left: 12px;
  color: var(--mint);
  font-family: var(--mono);
}

.article-body .deck-slide pre {
  max-height: 280px;
  margin: 24px 0 0;
  padding: 18px;
  box-shadow: inset 2px 0 var(--mint);
}

.deck-controls {
  display: grid;
  grid-template-columns: auto auto auto 1fr;
  align-items: center;
  gap: 8px;
  padding: 14px;
  border-top: 1px solid var(--line);
}

.deck-controls button {
  min-height: 38px;
  padding: 0 14px;
  border: 1px solid var(--line);
  border-radius: 5px;
  color: #c4d0ca;
  background: rgba(255, 255, 255, 0.02);
  font-family: var(--mono);
  font-size: 11px;
  cursor: pointer;
}

.deck-controls button:hover,
.deck-controls .deck-play[aria-pressed="true"] {
  border-color: rgba(var(--color-accent-rgb), 0.55);
  color: var(--acid);
  background: rgba(var(--color-accent-rgb), 0.07);
}

.deck-progress {
  height: 2px;
  margin: 0 12px;
  overflow: hidden;
  background: rgba(var(--color-border-rgb), 0.12);
}

.deck-progress i {
  width: 0;
  height: 100%;
  display: block;
  background: linear-gradient(90deg, var(--mint), var(--acid));
  transition: width 400ms ease;
}

@keyframes deck-in {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 720px) {
  .dynamic-deck {
    margin-bottom: 52px;
  }

  .deck-header {
    align-items: flex-start;
    padding: 20px;
  }

  .deck-stage {
    grid-template-columns: 1fr;
  }

  .deck-nav {
    display: flex;
    max-height: none;
    overflow-x: auto;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .deck-nav button {
    width: auto;
    min-width: 70px;
    display: block;
    padding: 12px;
    border-right: 1px solid rgba(var(--color-border-rgb), 0.08);
    border-bottom: 0;
  }

  .deck-nav button strong {
    display: none;
  }

  .deck-slide {
    min-height: 390px;
    padding: 28px 20px;
  }

  .deck-controls {
    grid-template-columns: 1fr 1fr 1fr;
  }

  .deck-controls button {
    padding: 0 8px;
  }

  .deck-progress {
    grid-column: 1 / -1;
    margin: 8px 2px 2px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .deck-slide {
    animation: none;
  }

  .deck-progress i {
    transition: none;
  }
}

/* HASHSET_STATE_EXPLAINER */
.hashset-lab {
  margin: 0 0 56px;
  border: 1px solid rgba(var(--color-accent-rgb), 0.28);
  border-radius: 20px;
  overflow: hidden;
  background: linear-gradient(145deg, rgba(18, 33, 27, 0.96), rgba(7, 17, 14, 0.98));
}
.hashset-lab__header {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  padding: 28px;
  border-bottom: 1px solid var(--line);
}
.hashset-lab__header span,
.hashset-label {
  color: var(--cyan);
  font: 700 11px/1.4 var(--mono);
  letter-spacing: .12em;
}
.hashset-lab__header h2 {
  margin: 8px 0 8px;
  font: 500 clamp(28px, 4vw, 44px)/1.1 var(--serif);
}
.hashset-lab__header p {
  max-width: 680px;
  margin: 0;
  color: var(--muted);
}
.hashset-lab__header > strong {
  flex: none;
  color: var(--muted);
  font: 500 13px/1 var(--mono);
}
.hashset-lab__header > strong b {
  color: var(--acid);
  font-size: 30px;
}
.hashset-stream {
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 18px 28px;
  border-bottom: 1px solid var(--line);
  color: var(--muted);
  font: 600 12px/1 var(--mono);
}
.hashset-stream > div {
  display: flex;
  gap: 8px;
}
.hashset-token,
.hashset-value {
  min-width: 38px;
  height: 38px;
  display: inline-grid;
  place-items: center;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--ink);
  background: rgba(255, 255, 255, .025);
  font: 700 13px/1 var(--mono);
}
.hashset-token.is-past {
  border-color: rgba(var(--color-interactive-rgb), .45);
  color: var(--mint);
}
.hashset-token.is-current {
  border-color: var(--acid);
  color: var(--color-bg);
  background: var(--acid);
  box-shadow: 0 0 0 4px rgba(var(--color-accent-rgb), .1);
}
.hashset-lab__stage {
  display: grid;
  grid-template-columns: 1fr 1.25fr 1fr;
  min-height: 230px;
}
.hashset-state,
.hashset-operation {
  padding: 28px;
}
.hashset-operation {
  border-inline: 1px solid var(--line);
}
.hashset-values {
  display: flex;
  flex-wrap: wrap;
  align-content: flex-start;
  gap: 9px;
  min-height: 58px;
  margin-top: 18px;
}
.hashset-values.is-empty::before {
  content: "∅  空集合";
  color: var(--muted);
  font: 500 13px/1.4 var(--mono);
}
.hashset-operation > strong {
  display: block;
  margin: 18px 0 10px;
  color: var(--ink);
  font: 700 clamp(18px, 3vw, 27px)/1.2 var(--mono);
}
.hashset-operation p {
  min-height: 54px;
  margin: 0;
  color: var(--muted);
}
.hashset-verdict {
  display: inline-flex;
  margin-top: 16px;
  padding: 7px 10px;
  border-radius: 6px;
  color: var(--muted);
  background: rgba(255, 255, 255, .04);
  font: 700 12px/1 var(--mono);
}
.hashset-verdict.is-true {
  color: var(--acid);
  background: rgba(var(--color-accent-rgb), .1);
}
.hashset-verdict.is-false {
  color: #ff9a8f;
  background: rgba(255, 106, 96, .1);
}
.hashset-code {
  padding: 16px 28px;
  border-block: 1px solid var(--line);
  background: rgba(0, 0, 0, .2);
  font: 500 13px/1.65 var(--mono);
}
.hashset-code > div {
  display: grid;
  grid-template-columns: 28px 1fr;
  padding: 5px 10px;
  border-left: 2px solid transparent;
  color: #819188;
}
.hashset-code > div.is-active {
  border-left-color: var(--acid);
  color: var(--ink);
  background: rgba(var(--color-accent-rgb), .07);
}
.hashset-code span {
  color: #617169;
}
.hashset-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
  padding: 18px 28px;
  border-bottom: 1px solid var(--line);
}
.hashset-controls button,
.hashset-playground button {
  min-height: 40px;
  padding: 0 15px;
  border: 1px solid var(--line);
  border-radius: 7px;
  color: var(--ink);
  background: transparent;
  cursor: pointer;
}
.hashset-controls button:hover,
.hashset-playground button:hover {
  border-color: var(--mint);
}
.hashset-controls button.is-primary,
.hashset-controls button.is-playing {
  border-color: var(--acid);
  color: var(--color-bg);
  background: var(--acid);
}
.hashset-controls button:disabled {
  cursor: not-allowed;
  opacity: .38;
}
.hashset-dots {
  flex: 1;
  min-width: 180px;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 5px;
}
.hashset-dots button {
  min-width: 0;
  width: 8px;
  height: 8px;
  min-height: 0;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: #314139;
}
.hashset-dots button.is-past { background: var(--mint); }
.hashset-dots button.is-active {
  width: 22px;
  border-radius: 5px;
  background: var(--acid);
}
.hashset-playground {
  display: grid;
  grid-template-columns: minmax(210px, .8fr) 1.2fr;
  gap: 24px;
  padding: 28px;
  background: rgba(var(--color-interactive-rgb), .035);
}
.hashset-playground h3 {
  margin: 8px 0;
  font: 500 25px/1.2 var(--serif);
}
.hashset-playground p {
  margin: 0;
  color: var(--muted);
}
.hashset-playground__actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}
.hashset-playground__actions label {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
}
.hashset-playground__actions input {
  min-width: 180px;
  min-height: 42px;
  padding: 0 13px;
  border: 1px solid var(--line);
  border-radius: 7px;
  outline: none;
  color: var(--ink);
  background: var(--color-bg);
}
.hashset-playground__actions input:focus {
  border-color: var(--cyan);
}
.hashset-playground__result {
  grid-column: 2;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: rgba(0, 0, 0, .18);
}
.hashset-playground__result > div > span {
  color: var(--muted);
  font: 600 11px/1 var(--mono);
}
.hashset-playground__result p {
  margin-top: 12px;
  color: var(--cyan);
  font-family: var(--mono);
}
@media (max-width: 900px) {
  .hashset-lab__stage { grid-template-columns: 1fr; }
  .hashset-operation { border-inline: 0; border-block: 1px solid var(--line); }
  .hashset-playground { grid-template-columns: 1fr; }
  .hashset-playground__result { grid-column: 1; }
}
@media (max-width: 620px) {
  .hashset-lab__header,
  .hashset-state,
  .hashset-operation,
  .hashset-playground { padding: 20px; }
  .hashset-lab__header { display: block; }
  .hashset-lab__header > strong { display: block; margin-top: 18px; }
  .hashset-stream,
  .hashset-controls,
  .hashset-code { padding-inline: 20px; }
  .hashset-stream { align-items: flex-start; flex-direction: column; }
  .hashset-dots { flex-basis: 100%; justify-content: flex-start; }
  .hashset-playground__actions input { width: 100%; }
}

@media (min-width: 901px) {
  .article-layout:has(.timeline-lab) {
    grid-template-columns: 190px minmax(0, 900px);
    gap: clamp(28px, 5vw, 64px);
  }
}

/* TIMELINE LIVE EDITOR */
.timeline-lab {
  --tl-label: 108px;
  --tl-cyan: var(--color-accent);
  --tl-amber: var(--color-warning);
  --tl-coral: var(--color-danger);
  --tl-mint: var(--color-interactive);
  margin: 0 0 72px;
  overflow: hidden;
  border: 1px solid rgba(var(--color-accent-rgb), .28);
  border-radius: 12px;
  background: var(--color-bg);
  box-shadow: 0 26px 70px rgba(0, 0, 0, .28);
}
.timeline-lab button,
.timeline-lab input { font-family: var(--mono); }
.timeline-lab__header {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 28px;
  padding: 26px;
  border-bottom: 1px solid var(--line);
  background: linear-gradient(105deg, rgba(var(--color-accent-rgb), .07), transparent 55%);
}
.timeline-lab__kicker,
.timeline-editor__toolbar span,
.timeline-preview__topline span,
.timeline-runtime header span {
  color: var(--tl-cyan);
  font: 700 10px/1.2 var(--mono);
  letter-spacing: .12em;
}
.article-body .timeline-lab__header h2 {
  margin: 8px 0 7px;
  padding: 0;
  border: 0;
  font-size: 29px;
}
.timeline-lab__header p { max-width: 560px; margin: 0; color: #b5c8bf; font-size: 14px; line-height: 1.7; }
.timeline-lab__settings { display: flex; align-items: end; gap: 10px; }
.timeline-lab__settings label { display: grid; gap: 6px; color: var(--muted); font: 600 10px/1 var(--mono); }
.timeline-lab__settings input {
  width: 82px;
  min-height: 38px;
  padding: 0 10px;
  border: 1px solid var(--line);
  border-radius: 6px;
  outline: none;
  color: var(--ink);
  background: #050b09;
}
.timeline-lab__settings input:focus { border-color: var(--tl-cyan); box-shadow: 0 0 0 2px rgba(var(--color-accent-rgb), .1); }
.timeline-lab__settings input:invalid { border-color: var(--tl-coral); }
.timeline-lab__notice { min-height: 38px; padding: 9px 26px; border-bottom: 1px solid var(--line); color: var(--color-text-muted); background: rgba(var(--color-success-rgb), .035); font: 500 11px/1.7 var(--mono); }
.timeline-lab__notice.is-error { color: #ffd2cd; background: rgba(255, 131, 120, .09); }
.timeline-lab__workspace { display: grid; grid-template-columns: minmax(0, 1.45fr) minmax(240px, .8fr); min-height: 420px; }
.timeline-editor { min-width: 0; border-right: 1px solid var(--line); }
.timeline-editor__toolbar,
.timeline-preview__topline,
.timeline-runtime header {
  min-height: 53px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 0 18px;
  border-bottom: 1px solid var(--line);
}
.timeline-editor__toolbar strong { display: block; margin-top: 5px; color: #d9e7df; font: 600 11px/1 var(--mono); }
.timeline-editor__readout { display: flex; align-items: baseline; gap: 7px; color: var(--muted); font: 600 10px/1 var(--mono); }
.timeline-editor__readout b { color: var(--acid); font-size: 20px; }
.timeline-editor__readout span { color: var(--muted); font-size: 10px; letter-spacing: 0; }
.timeline-editor__scroll { overflow-x: auto; overflow-y: hidden; scrollbar-color: rgba(var(--color-accent-rgb), .35) var(--color-bg); }
.timeline-editor__canvas { position: relative; min-width: 540px; }
.timeline-ruler { display: grid; grid-template-columns: var(--tl-label) 1fr; height: 43px; border-bottom: 1px solid var(--line); background: #080f0d; }
.timeline-ruler__label { display: grid; place-items: center; border-right: 1px solid var(--line); color: var(--muted); font: 700 9px/1 var(--mono); letter-spacing: .1em; }
.timeline-ruler__ticks { display: grid; grid-template-columns: repeat(var(--timeline-frames), minmax(0, 1fr)); }
.timeline-ruler__ticks button { min-width: 0; padding: 0; border: 0; border-left: 1px solid rgba(var(--color-border-rgb), .1); color: var(--color-text-dim); background: transparent; font-size: 8px; cursor: pointer; }
.timeline-ruler__ticks button:hover,
.timeline-ruler__ticks button.is-current { color: var(--color-bg); background: var(--acid); }
.timeline-track { display: grid; grid-template-columns: var(--tl-label) 1fr; min-height: 62px; border-bottom: 1px solid var(--line); }
.timeline-track__label { display: flex; flex-direction: column; justify-content: center; padding: 0 13px; border-right: 1px solid var(--line); background: rgba(255,255,255,.012); }
.timeline-track__label span { color: var(--ink); font-size: 13px; }
.timeline-track__label small { margin-top: 4px; color: var(--muted); font: 700 8px/1 var(--mono); letter-spacing: .1em; }
.timeline-track__body {
  position: relative;
  background-image: repeating-linear-gradient(90deg, transparent 0, transparent calc((100% / var(--timeline-frames)) - 1px), rgba(var(--color-border-rgb), .085) calc((100% / var(--timeline-frames)) - 1px), rgba(var(--color-border-rgb), .085) calc(100% / var(--timeline-frames)));
}
.timeline-clip { position: absolute; top: 9px; bottom: 9px; display: grid; grid-template-columns: 8px minmax(0, 1fr) 8px; overflow: hidden; border: 1px solid currentColor; border-radius: 5px; color: var(--tl-cyan); background: color-mix(in srgb, currentColor 16%, var(--color-surface)); cursor: grab; touch-action: none; box-shadow: inset 0 0 22px rgba(255,255,255,.025); }
.timeline-clip.is-amber { color: var(--tl-amber); }
.timeline-clip.is-coral { color: var(--tl-coral); }
.timeline-clip.is-mint { color: var(--tl-mint); }
.timeline-clip.is-active { box-shadow: 0 0 18px color-mix(in srgb, currentColor 20%, transparent), inset 0 0 0 1px currentColor; }
.timeline-clip.is-dragging { cursor: grabbing; }
.timeline-clip > button { width: 8px; padding: 0; border: 0; color: inherit; background: currentColor; opacity: .35; cursor: ew-resize; touch-action: none; }
.timeline-clip > button:hover { opacity: .8; }
.timeline-clip > span { min-width: 0; display: flex; flex-direction: column; justify-content: center; padding: 0 7px; }
.timeline-clip b { overflow: hidden; color: #f4faf6; font: 600 10px/1.2 var(--sans); text-overflow: ellipsis; white-space: nowrap; }
.timeline-clip small { margin-top: 4px; color: currentColor; font: 700 8px/1 var(--mono); }
.timeline-playhead { --playhead-position: 0%; position: absolute; z-index: 6; top: 0; bottom: 0; left: var(--tl-label); width: 1px; padding: 0; border: 0; color: #fff; background: currentColor; cursor: ew-resize; touch-action: none; }
.timeline-playhead i { position: absolute; top: 0; left: -5px; width: 11px; height: 9px; background: currentColor; clip-path: polygon(0 0,100% 0,50% 100%); }
.timeline-playhead span { position: absolute; top: 9px; left: 7px; padding: 2px 5px; color: var(--color-bg); background: var(--color-text); font: 800 8px/1 var(--mono); }
.timeline-editor__hint { margin: 0; padding: 11px 18px; color: var(--muted); font: 500 10px/1.5 var(--mono); }
.timeline-preview { min-width: 0; background: radial-gradient(circle at 50% 48%, rgba(115,221,255,.07), transparent 50%); }
.timeline-preview__topline strong { color: var(--acid); font: 700 10px/1 var(--mono); }
.timeline-stage { position: relative; height: 270px; overflow: hidden; border-bottom: 1px solid var(--line); background: linear-gradient(180deg, var(--color-surface) 0 70%, var(--color-surface-raised) 70%); }
.timeline-stage__grid { position: absolute; inset: 70% 0 0; opacity: .2; background-image: linear-gradient(rgba(115,221,255,.25) 1px,transparent 1px),linear-gradient(90deg,rgba(115,221,255,.25) 1px,transparent 1px); background-size: 24px 16px; transform: perspective(100px) rotateX(30deg); transform-origin: top; }
.timeline-actor,
.timeline-target { position: absolute; bottom: 62px; width: 48px; height: 82px; transition: transform .16s ease; }
.timeline-actor { left: 17%; transform-origin: 50% 100%; }
.timeline-target { right: 15%; }
.timeline-actor i { position: absolute; display: block; background: var(--tl-cyan); }
.timeline-actor__head { top: 0; left: 15px; width: 20px; height: 20px; border: 2px solid var(--color-bg); border-radius: 50%; }
.timeline-actor__body { top: 20px; left: 13px; width: 24px; height: 42px; border-radius: 7px 7px 4px 4px; }
.timeline-actor__arm { top: 28px; left: 32px; width: 36px; height: 8px; border-radius: 4px; transform-origin: left; }
.timeline-actor span,
.timeline-target span { position: absolute; top: 87px; left: 50%; color: var(--muted); font: 700 8px/1 var(--mono); transform: translateX(-50%); }
.timeline-target i { position: absolute; inset: 6px 8px 10px; display: block; border: 2px solid var(--tl-coral); border-radius: 50% 50% 42% 42%; background: rgba(255,131,120,.08); }
.timeline-stage[data-action-phase="windup"] .timeline-actor { transform: translateX(-7px) rotate(-8deg); }
.timeline-stage[data-action-phase="windup"] .timeline-actor__arm { transform: rotate(-50deg); }
.timeline-stage[data-action-phase="strike"] .timeline-actor { transform: translateX(25px) rotate(7deg); }
.timeline-stage[data-action-phase="strike"] .timeline-actor__arm { transform: rotate(4deg) scaleX(1.8); }
.timeline-stage[data-action-phase="recover"] .timeline-actor { transform: translateX(9px); }
.timeline-attack { position: absolute; top: 96px; left: 32%; width: 40%; height: 60px; border-top: 3px solid var(--tl-coral); border-radius: 50%; opacity: 0; transform: rotate(-8deg) scaleX(.5); transform-origin: left; }
.timeline-stage.has-hit .timeline-attack { opacity: 1; animation: timeline-slash .32s ease-out both; }
.timeline-stage.has-hit .timeline-target { animation: timeline-target-hit .32s ease-out both; }
.timeline-sound { position: absolute; left: 28%; bottom: 92px; display: flex; align-items: center; gap: 3px; opacity: 0; }
.timeline-sound i { width: 3px; height: 12px; background: var(--tl-amber); animation: timeline-sound .55s ease-in-out infinite alternate; }
.timeline-sound i:nth-child(2) { animation-delay: .12s; }
.timeline-sound i:nth-child(3) { animation-delay: .24s; }
.timeline-stage.has-audio .timeline-sound { opacity: 1; }
.timeline-stage.is-interrupted .timeline-actor { filter: grayscale(.7); transform: none; }
.timeline-stage__caption { position: absolute; right: 14px; bottom: 12px; left: 14px; color: var(--color-text-muted); font-size: 11px; line-height: 1.45; text-align: center; }
.timeline-entity-state { display: grid; grid-template-columns: repeat(2, 1fr); }
.timeline-entity-state > div { min-width: 0; padding: 13px 14px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.timeline-entity-state span { display: block; color: var(--muted); font: 700 8px/1 var(--mono); }
.timeline-entity-state strong { display: block; margin-top: 6px; overflow: hidden; color: #e5f2eb; font-size: 11px; text-overflow: ellipsis; white-space: nowrap; }
.timeline-runtime { display: grid; grid-template-columns: .8fr 1.15fr 1.05fr; border-top: 1px solid var(--line); }
.timeline-runtime > section { min-width: 0; border-right: 1px solid var(--line); }
.timeline-runtime > section:last-child { border-right: 0; }
.timeline-runtime header { min-height: 44px; padding-inline: 14px; }
.timeline-runtime header b { color: var(--acid); font: 700 10px/1 var(--mono); }
.timeline-runtime header button { padding: 4px 7px; border: 1px solid var(--line); border-radius: 4px; color: var(--muted); background: transparent; font-size: 8px; cursor: pointer; }
.timeline-runtime__tasks > div,
.timeline-runtime__log ol,
.timeline-runtime__code > div { height: 212px; overflow: auto; }
.timeline-task { display: grid; grid-template-columns: 38px 1fr; gap: 3px 8px; padding: 11px 13px; border-bottom: 1px solid var(--line); border-left: 2px solid currentColor; color: var(--tl-cyan); }
.timeline-task.is-amber { color: var(--tl-amber); }.timeline-task.is-coral { color: var(--tl-coral); }.timeline-task.is-mint { color: var(--tl-mint); }
.timeline-task span { grid-row: span 2; color: currentColor; font: 700 8px/1 var(--mono); }
.timeline-task strong { color: #e8f2ed; font-size: 10px; }.timeline-task small { color: var(--muted); font: 500 8px/1 var(--mono); }
.timeline-runtime__empty { margin: 0; padding: 20px 14px; color: var(--muted); font-size: 11px; }
.timeline-runtime__log ol { margin: 0; padding: 0; list-style: none; }
.timeline-runtime__log li { display: grid; grid-template-columns: 31px 55px 1fr; gap: 7px; align-items: center; margin: 0; padding: 8px 11px; border-bottom: 1px solid var(--line); font: 600 8px/1.35 var(--mono); }
.timeline-runtime__log li b { color: #dce8e2; }.timeline-runtime__log li span { color: var(--tl-cyan); }.timeline-runtime__log li p { margin: 0; color: var(--muted); font-size: 9px; }
.timeline-runtime__log li.is-finish span { color: var(--tl-mint); }.timeline-runtime__log li.is-interrupt span { color: var(--tl-coral); }.timeline-runtime__log li.is-catchup span { color: var(--tl-amber); }
.timeline-runtime__log li.is-empty { display: block; padding: 18px 14px; color: var(--muted); }
.timeline-runtime__code p { display: grid; grid-template-columns: 24px 1fr; margin: 0; padding: 8px 10px; border-left: 2px solid transparent; color: #8da098; }
.timeline-runtime__code p.is-active { border-color: var(--acid); color: #eef4ec; background: rgba(197,245,74,.07); }
.timeline-runtime__code p span { color: #63736b; font: 700 8px/1.5 var(--mono); }
.article-body .timeline-runtime__code code { padding: 0; border: 0; color: inherit; background: transparent; font: 500 9px/1.5 var(--mono); }
.timeline-lab__controls { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 8px; padding: 14px 18px; border-top: 1px solid var(--line); background: #080f0d; }
.timeline-lab__controls button { min-height: 38px; padding: 0 13px; border: 1px solid var(--line); border-radius: 5px; color: #d5e2db; background: transparent; font-size: 10px; cursor: pointer; }
.timeline-lab__controls button:hover:not(:disabled) { border-color: var(--tl-cyan); color: var(--tl-cyan); }
.timeline-lab__controls button.is-primary { border-color: var(--acid); color: var(--color-bg); background: var(--acid); }
.timeline-lab__controls button.is-danger { color: #ffb2aa; }.timeline-lab__controls button:disabled { opacity: .35; cursor: not-allowed; }
@keyframes timeline-slash { from { transform: rotate(-8deg) scaleX(.25); } to { transform: rotate(-8deg) scaleX(1); } }
@keyframes timeline-target-hit { 50% { filter: brightness(2); transform: translateX(8px); } }
@keyframes timeline-sound { from { height: 7px; } to { height: 22px; } }
@media (max-width: 820px) {
  .timeline-lab__header { grid-template-columns: 1fr; }
  .timeline-lab__settings { justify-content: flex-start; }
  .timeline-lab__workspace { grid-template-columns: 1fr; }
  .timeline-editor { border-right: 0; border-bottom: 1px solid var(--line); }
  .timeline-runtime { grid-template-columns: 1fr 1fr; }
  .timeline-runtime__code { grid-column: 1 / -1; border-top: 1px solid var(--line); }
}
@media (max-width: 560px) {
  .timeline-lab { --tl-label: 84px; }
  .timeline-lab__header { padding: 20px; }
  .article-body .timeline-lab__header h2 { font-size: 25px; }
  .timeline-lab__notice { padding-inline: 20px; }
  .timeline-runtime { grid-template-columns: 1fr; }
  .timeline-runtime__code { grid-column: auto; }
  .timeline-runtime > section { border-right: 0; border-bottom: 1px solid var(--line); }
  .timeline-lab__controls { justify-content: stretch; }
  .timeline-lab__controls button { flex: 1 1 calc(50% - 8px); }
}
/* ── Shared navigation and information architecture ───────────────────── */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.knowledge-header {
  background: rgba(8, 12, 18, 0.9);
}

.knowledge-menu-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  background: var(--panel);
  cursor: pointer;
}

.knowledge-menu-toggle i,
.knowledge-menu-toggle i::before {
  width: 14px;
  height: 1px;
  display: block;
  background: currentColor;
  content: "";
}

.knowledge-menu-toggle i::before {
  transform: translateY(5px);
}

.knowledge-nav-links {
  gap: 18px;
}

.knowledge-nav-search {
  display: flex;
}

.knowledge-nav-search input {
  min-width: 0;
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  outline: none;
  color: var(--ink);
  background: var(--panel);
  font-size: 13px;
}

.knowledge-nav-search input:focus {
  border-color: var(--acid);
  box-shadow: 0 0 0 3px rgba(var(--color-accent-rgb), 0.12);
}
.knowledge-nav-search button {
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-left: 0;
  border-radius: 0 8px 8px 0;
  color: var(--acid);
  background: var(--panel);
  cursor: pointer;
}

.reading-progress {
  position: absolute;
  right: 0;
  bottom: -1px;
  left: 0;
  height: 2px;
  overflow: hidden;
}

.reading-progress i {
  width: 100%;
  height: 100%;
  display: block;
  background: var(--acid);
  transform: scaleX(0);
  transform-origin: left;
}

.article-context,
.library-context {
  padding-top: 24px;
}

.breadcrumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  overflow: hidden;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 11px;
  white-space: nowrap;
}

.breadcrumbs > * {
  overflow: hidden;
  text-overflow: ellipsis;
}

.breadcrumbs > * + *::before {
  margin-right: 8px;
  color: var(--color-text-dim);
  content: "/";
}

.breadcrumbs [aria-current="page"] {
  color: var(--ink);
}

.category-strip {
  margin-top: 18px;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  align-items: baseline;
  gap: 18px;
  border-block: 1px solid var(--line);
}

.category-strip > span {
  padding: 12px 0;
  color: var(--color-text-dim);
  font: 700 11px/1.4 var(--mono);
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.category-strip > div {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px;
}

.category-strip a {
  flex: 0 0 auto;
  padding: 12px 10px;
  color: var(--muted);
  font-size: 13px;
}

.category-strip a:hover,
.category-strip a[aria-current="page"] {
  color: var(--acid);
}

.category-strip a[aria-current="page"] {
  box-shadow: inset 0 -2px var(--acid);
}

.category-strip small {
  margin-left: 6px;
  color: var(--color-text-dim);
  font: 10px var(--mono);
}

.article-context + .article-hero {
  padding-top: 54px;
}

.toc {
  border: 0;
}

.toc summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 14px;
  color: var(--ink);
  cursor: pointer;
  list-style: none;
}

.toc summary::-webkit-details-marker {
  display: none;
}

.toc summary span,
.toc summary strong {
  margin: 0;
  font: 700 11px/1.4 var(--mono);
  letter-spacing: 0.12em;
}

.toc summary span {
  color: var(--ink);
}

.toc nav {
  display: block;
}

.article-groups {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.article-group {
  align-self: start;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
}

.article-group summary {
  min-height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 18px 20px;
  cursor: pointer;
  list-style: none;
}

.article-group summary::-webkit-details-marker {
  display: none;
}

.article-group summary span {
  font-family: var(--serif);
  font-size: 21px;
}

.article-group summary small {
  color: var(--acid);
  font: 10px var(--mono);
  letter-spacing: 0.08em;
}

.article-group[open] summary {
  border-bottom: 1px solid var(--line);
}

.article-list {
  display: grid;
}

.article-list .article-card {
  min-height: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 18px;
  padding: 18px 20px;
  border: 0;
  border-bottom: 1px solid var(--line);
  border-radius: 0;
  background: transparent;
}

.article-list .article-card:last-child {
  border-bottom: 0;
}

.article-list .article-card:hover {
  background: var(--panel-strong);
  transform: none;
}

.article-list .article-card h3 {
  margin: 0 0 5px;
  font-size: 18px;
}

.article-list .article-card p {
  display: -webkit-box;
  overflow: hidden;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 2;
}

.article-list .card-arrow {
  margin: 0;
  color: var(--acid);
}

@media (max-width: 900px) {
  .toc {
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: 8px;
  }

  .toc:not([open]) summary {
    margin-bottom: 0;
  }
}

@media (max-width: 620px) {
  .section-heading {
    align-items: flex-start;
    flex-direction: column;
    gap: 8px;
  }

  .knowledge-menu-toggle {
    display: inline-flex;
  }

  .knowledge-nav-links {
    position: absolute;
    top: 68px;
    right: 12px;
    left: 12px;
    display: none;
    align-items: stretch;
    padding: 12px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: var(--panel-strong);
    box-shadow: 0 24px 70px rgba(0, 0, 0, 0.42);
  }

  .knowledge-nav-links.is-open {
    display: grid;
  }

  .knowledge-nav-links a,
  .knowledge-nav-search input {
    width: 100%;
    padding: 12px;
  }

  .knowledge-nav-links a:first-child {
    display: block;
  }

  .article-groups {
    grid-template-columns: 1fr;
  }

  .article-list .article-card {
    grid-template-columns: 1fr;
  }

  .article-list .card-arrow {
    display: none;
  }

  .category-strip {
    margin-inline: -12px;
    padding-inline: 12px;
  }
}