/* Share the homepage's official fonts, including its Korean Unicode subsets.
   Absolute URLs also work when this repository is served on its own. */
@import url("https://icarlaboratory.github.io/assets/fonts/pretendardvariable-dynamic-subset.css");
@font-face {
  font-family: "JetBrains Mono";
  src: url("https://icarlaboratory.github.io/assets/fonts/jetbrains-mono-subset.woff2") format("woff2");
  font-weight: 100 800;
  font-style: normal;
  font-display: swap;
}

:root {
  --bg: #fff;
  --bg-soft: #f5f5f3;
  --surface: #fff;
  --ink: #0a0a0a;
  --muted: #55555c;
  --faint: #666670;
  --line: rgba(10, 10, 10, .17);
  --line-soft: rgba(10, 10, 10, .09);
  --panel: rgba(10, 10, 10, .028);
  --panel-2: rgba(10, 10, 10, .055);
  /* Color encodes measured/target signals, never navigation or branding. */
  --actual: #087f74;
  --target: #c56b31;
  --sans: "Pretendard Variable", Pretendard, Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", "Apple SD Gothic Neo", "Malgun Gothic", sans-serif;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --pad: clamp(1.25rem, 5vw, 3rem);
  --maxw: 1140px;
  --radius: 16px;
}

/* Shared page shell */
*, *::before, *::after { box-sizing: border-box; }
body { margin: 0; color: var(--ink); background: var(--bg); font-family: var(--sans); font-size: 16.5px; line-height: 1.65; word-break: keep-all; -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration: none; }
button, input { font: inherit; }
button, a, input { touch-action: manipulation; }
button { cursor: pointer; background: var(--surface); color: var(--ink); border: 1px solid var(--line); border-radius: 999px; padding: 10px 15px; min-height: 44px; }
button:disabled { cursor: not-allowed; opacity: .5; }
button:hover:not(:disabled) { border-color: var(--ink); background: var(--bg-soft); }
:focus-visible { outline: 2px solid var(--ink); outline-offset: 4px; }
::selection { background: var(--ink); color: var(--bg); }
h1, h2, h3, p { margin: 0; }
h1 { font-size: clamp(2.3rem, 4.5vw, 3.4rem); letter-spacing: -.042em; line-height: 1.08; font-weight: 750; text-wrap: balance; }
h2 { font-size: clamp(1.55rem, 2.6vw, 2rem); letter-spacing: -.035em; line-height: 1.18; font-weight: 700; text-wrap: balance; }
h3 { font-size: 1.3rem; letter-spacing: -.028em; line-height: 1.4; font-weight: 700; }
.site-header, .site-footer { background: var(--ink); color: #fafafa; padding-inline: max(var(--pad), calc((100% - var(--maxw)) / 2 + var(--pad))); }
.site-header { min-height: 69px; display: flex; align-items: center; justify-content: space-between; gap: 16px; }
.site-header :focus-visible, .site-footer :focus-visible { outline-color: #fafafa; }
.brand { display: flex; align-items: center; gap: 10px; min-width: 0; padding-block: 12px; }
/* The laboratory symbol, shared with the homepage header. Decorative next to
   the accessible brand label, so the img stays alt-empty. */
.brand-mark { width: 32px; height: 32px; flex: none; display: grid; place-items: center; }
.brand-mark img { width: 100%; height: 100%; object-fit: contain; }
/* Lab-style inverted language pill, without the generic action-button height. */
.language-switch { display: inline-flex; flex-shrink: 0; align-items: center; gap: 2px; padding: 3px; border: 1px solid rgba(255, 255, 255, .19); border-radius: 999px; }
.language-switch button[data-lang] { min-height: 30px; padding: 6px 11px; border: 0; background: transparent; color: #a7a7ae; font: 500 13px/18px var(--sans); white-space: nowrap; }
.language-switch button[data-lang]:hover { color: #fafafa; background: rgba(255, 255, 255, .1); }
.language-switch button[data-lang][aria-pressed=true] { color: var(--ink); background: #fafafa; }
.language-switch button[data-lang]:focus-visible { outline: 2px solid #fafafa; outline-offset: 3px; }
.brand-label { font: 600 11px/1.5 var(--mono); letter-spacing: 1.7px; }
.container { max-width: var(--maxw); padding: 0 var(--pad); margin: auto; }
.eyebrow {
  display: flex; align-items: center; gap: .75rem;
  color: var(--ink); font: 600 1rem/1.5 var(--sans);
  letter-spacing: normal; text-transform: uppercase; margin-bottom: 1.25rem;
}
.eyebrow::after { content: ""; flex: 1; height: 1px; background: linear-gradient(90deg, var(--line), transparent); }
.site-footer { padding-block: 44px 36px; display: flex; flex-wrap: wrap; align-items: baseline; justify-content: space-between; gap: 16px 32px; font-size: 13px; }
.site-footer strong { font: 600 .95rem/1.4 var(--sans); letter-spacing: -.01em; }
.footer-tag { display: block; margin-top: 4px; color: #a7a7ae; font: 500 .6rem/1.6 var(--mono); letter-spacing: .16em; text-transform: uppercase; }
.site-footer a { color: #a7a7ae; }
.site-footer a:hover { color: #fafafa; text-decoration: underline; text-underline-offset: 3px; }
[hidden] { display: none !important; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; border: 0; }
.skip { position: absolute; left: 10px; top: -100px; background: var(--surface); padding: 12px; z-index: 3; border-radius: 999px; }
.skip:focus { top: 10px; }

/* Catalog */
.intro { padding: clamp(48px, 7vw, 80px) 0 32px; display: flex; align-items: center; justify-content: space-between; gap: 32px; }
.intro-copy { margin-top: 18px; color: var(--muted); font-size: 16px; max-width: 62ch; }
.catalog-stats {
  display: grid; grid-template-columns: repeat(2, minmax(118px, 1fr));
  flex-shrink: 0; gap: 1px; background: var(--line-soft);
  border: 1px solid var(--line-soft); border-radius: var(--radius); overflow: hidden;
}
.catalog-stats div { display: flex; flex-direction: column; background: var(--bg); padding: 22px 22px 18px; }
.catalog-stats strong { font: 700 clamp(30px, 3vw, 38px)/1 var(--sans); letter-spacing: -.045em; }
.catalog-stats span { color: var(--muted); font-size: 12px; margin-top: 9px; }
.catalog-section { border-top: 1px solid var(--line-soft); padding-top: clamp(36px, 5vw, 56px); padding-bottom: clamp(48px, 7vw, 80px); }
.section-top, .filter-row, .results-row { display: flex; align-items: center; justify-content: space-between; gap: 20px; }
.section-index { font: 500 11px/1.5 var(--mono); letter-spacing: .18em; color: var(--faint); margin-left: 12px; white-space: nowrap; }
.search-wrap { display: flex; align-items: center; background: var(--surface); border: 1px solid var(--line); border-radius: 999px; min-width: 270px; padding: 0 16px; gap: 8px; }
.search-wrap > span:first-child { font-size: 23px; color: var(--muted); }
.search-wrap input { border: 0; background: transparent; color: var(--ink); min-width: 0; width: 100%; padding: 10px 0; min-height: 44px; font-size: 13px; }
.filter-row { padding: 24px 0 18px; border-bottom: 1px solid var(--line-soft); }
.category-filters { display: flex; gap: 6px; flex-wrap: wrap; }
/* Compact filters deliberately override the generic 44px action height. */
.category-filters button {
  border: 1px solid var(--line-soft); background: transparent; color: var(--muted);
  font-family: var(--mono); font-size: .7rem; letter-spacing: .11em; text-transform: uppercase;
  line-height: 20px; min-height: 32px; padding: 5px 13px;
  transition: color .2s, border-color .2s, background .2s;
}
.category-filters button:hover:not([aria-pressed=true]) { color: var(--ink); border-color: var(--line); background: transparent; }
.category-filters button[aria-pressed=true] { background: var(--ink); border-color: var(--ink); color: var(--bg); font-weight: 600; }
.category-filters button span { margin-left: 7px; font: 11px/1.5 var(--mono); letter-spacing: 0; }
.ready-filter { font-size: 13px; display: flex; align-items: center; gap: 8px; white-space: nowrap; min-height: 44px; cursor: pointer; }
input[type=checkbox] { accent-color: var(--ink); height: 16px; width: 16px; }
.results-row { padding: 18px 0; font-size: 12px; color: var(--muted); }
.results-row strong { color: var(--ink); }
.catalog-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; }
.sim-card {
  position: relative; background: var(--panel); border: 1px solid var(--line-soft);
  border-radius: var(--radius); overflow: hidden; display: flex; flex-direction: column;
  transition: transform .28s cubic-bezier(.2, .7, .3, 1), border-color .28s, background .28s;
}
.sim-card::before { content: ""; position: absolute; inset: 0 0 auto 0; height: 1px; background: var(--ink); opacity: 0; transition: opacity .28s; z-index: 1; }
.sim-card:hover { transform: translateY(-4px); border-color: var(--line); background: var(--panel-2); }
.sim-card:hover::before { opacity: 1; }
.card-visual { height: 225px; padding-top: 43px; position: relative; border-bottom: 1px solid var(--line-soft); background: var(--bg-soft); }
.card-preview { display: block; width: 100%; height: 100%; object-fit: contain; }
.card-visual .card-number { position: absolute; left: 17px; top: 14px; font: 500 11px/1.5 var(--mono); letter-spacing: .18em; color: var(--faint); }
.card-status { position: absolute; right: 13px; top: 12px; padding: 3px 8px; border-radius: 999px; font-size: 12px; background: var(--surface); color: var(--muted); border: 1px solid var(--line-soft); }
.card-status.ready { background: var(--ink); color: var(--bg); border-color: var(--ink); }
.card-status.ready::before { content: '●'; font-size: 7px; margin-right: 5px; }
.card-body { padding: 22px 20px 20px; display: flex; flex: 1; flex-direction: column; }
.card-category { color: var(--muted); font-size: 12px; margin-bottom: 7px; }
.card-body h3 { font-size: 1.3rem; letter-spacing: -.028em; text-wrap: balance; }
.english-name { font: 12px/1.6 var(--mono); color: var(--faint); margin-top: 5px; }
.card-description { color: var(--muted); font-size: 15px; line-height: 1.7; margin-top: 14px; min-height: 48px; }
.features { display: flex; gap: 5px; flex-wrap: wrap; margin: 18px 0 22px; }
.features span { font-size: 12px; background: var(--panel); color: var(--muted); border: 1px solid var(--line-soft); padding: 4px 9px; border-radius: 999px; }
.card-footer { border-top: 1px solid var(--line-soft); padding-top: 14px; margin-top: auto; display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; align-items: center; }
.source-link { font-size: 13px; color: var(--muted); overflow-wrap: anywhere; }
.source-link:hover { color: var(--ink); text-decoration: underline; text-underline-offset: 3px; }
.launch { display: inline-flex; align-items: center; gap: 12px; font-size: 12px; line-height: 1.5; color: var(--bg); background: var(--ink); border-radius: 999px; font-weight: 600; padding: 6px 13px; }
.launch:hover { opacity: .86; }
.planned-label { font-size: 12px; color: var(--faint); }
.intro-guide { margin-top: 22px; color: var(--muted); font-size: 13px; }
.intro-guide > p { color: var(--ink); font-weight: 600; margin-bottom: 8px; }
.intro-steps { display: flex; flex-wrap: wrap; gap: 8px 18px; list-style: none; padding: 0; margin: 0; counter-reset: step; }
.intro-steps li { counter-increment: step; }
.intro-steps li::before { content: "0" counter(step); font: 11px var(--mono); color: var(--ink); margin-right: 7px; }
.empty-state { text-align: center; padding: 55px 20px; border: 1px dashed var(--line); border-radius: var(--radius); }
.empty-state p { margin: 10px 0 18px; color: var(--muted); }

/* Experiment workspace */
.back-link { font-size: 13px; color: var(--muted); display: inline-block; margin: 28px 0 24px; }
.back-link:hover { color: var(--ink); text-decoration: underline; }
.sim-heading { display: flex; justify-content: space-between; align-items: center; margin-bottom: 32px; gap: 20px; }
.sim-heading p:last-child { color: var(--muted); margin-top: 14px; font-size: 15px; }
.status { font: 11px var(--mono); color: var(--muted); padding: 8px 12px; background: var(--bg-soft); border: 1px solid var(--line-soft); border-radius: 999px; white-space: nowrap; }
.sim-layout { display: grid; grid-template-columns: minmax(0, 1fr) 300px; align-items: start; gap: 22px; }
.panel { background: var(--surface); border: 1px solid var(--line-soft); border-radius: var(--radius); overflow: hidden; }
.panel-heading { display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 18px 20px; border-bottom: 1px solid var(--line-soft); }
.panel-heading h2 { font-size: 1rem; font-weight: 600; letter-spacing: -.01em; }
.mono { font: 500 11px/1.5 var(--mono); letter-spacing: .14em; text-transform: uppercase; color: var(--faint); }
canvas { display: block; width: 100%; }
#apparatus { height: 245px; background: var(--bg-soft); }
#response { height: 205px; }
.canvas-caption { font-size: 12px; color: var(--muted); padding: 12px 20px; }
.metrics { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); margin: 16px 0; border: 1px solid var(--line-soft); background: var(--bg-soft); border-radius: var(--radius); overflow: hidden; }
.metrics div { padding: 14px 12px; border-right: 1px solid var(--line-soft); }
.metrics div:last-child { border: 0; }
.metrics span { display: block; font-size: 12px; color: var(--muted); margin-bottom: 6px; }
.metrics strong { font: 600 21px/1.4 var(--mono); letter-spacing: -.045em; }
.metrics small { font-size: 12px; color: var(--muted); letter-spacing: 0; }
.metrics div:nth-child(2) strong { color: var(--actual); }
.legend { display: flex; gap: 17px; font-size: 12px; }
.legend span::before { content: ''; display: inline-block; width: 18px; vertical-align: middle; margin-right: 6px; border-top: 2px solid var(--actual); }
.legend .target-line::before { border-top: 2px dashed var(--target); }
.controls { padding-bottom: 18px; }
.controls .panel-heading { padding: 18px 19px; }
.action-buttons { display: flex; gap: 8px; padding: 18px 19px 9px; }
.action-buttons button { flex: 1; font-size: 13px; }
.primary { background: var(--ink); border-color: var(--ink); color: var(--bg); }
.primary:hover:not(:disabled) { background: var(--ink); color: var(--bg); opacity: .86; }
.disturb-button { display: block; width: calc(100% - 38px); margin: 0 19px; font-size: 13px; background: var(--bg-soft); }
.control-help { padding: 12px 19px 16px; color: var(--muted); font-size: 12px; border-bottom: 1px solid var(--line-soft); }
/* Action explanations remain visible, including in the compact mobile controls. */
#disturbance-help { display: block; font-size: 13px; line-height: 1.65; }
.parameter { padding: 16px 19px 0; }
.parameter label { display: flex; align-items: center; justify-content: space-between; gap: 6px; font-size: 13px; font-weight: 600; }
.parameter output { font: 12px var(--mono); color: var(--ink); padding: 3px 7px; background: var(--bg-soft); border-radius: 5px; }
.parameter input[type=range] { width: 100%; accent-color: var(--ink); cursor: pointer; height: 27px; display: block; margin: 7px 0 0; }
.parameter p { font-size: 12px; color: var(--muted); line-height: 1.65; }
.parameter .range-limits { display: flex; justify-content: space-between; font: 11px/1.5 var(--mono); color: var(--faint); margin-bottom: 6px; }
.experiment-tip { background: var(--bg-soft); padding: 12px; margin: 20px 19px 0; border-left: 2px solid var(--ink); font-size: 12px; }
.experiment-tip p { margin-top: 5px; color: var(--muted); }
.simulation-message { font-size: 12px; color: var(--muted); padding: 14px 19px 0; }
.simulation-message.error { color: #a33f2a; }
.model-notes { margin: 32px 0 48px; padding: 24px; background: var(--bg-soft); }
.model-notes h2 { font-size: 17px; margin-bottom: 12px; }
.model-notes p { font-size: 13px; color: var(--muted); margin-bottom: 10px; }
.model-notes a { font-size: 13px; text-decoration: underline; text-underline-offset: 3px; }

/* Control-loop diagrams keep readable labels instead of shrinking on phones. */
.control-loop { margin-top: 28px; }
.loop-scroll-help { display: none; padding: 12px 20px; font-size: 12px; color: var(--muted); }
.loop-viewport { overflow-x: auto; background: var(--bg-soft); }
.loop-notes summary { padding: 14px 20px; min-height: 44px; cursor: pointer; font-size: 13px; border-top: 1px solid var(--line-soft); }
.loop-notes summary:hover { background: var(--bg-soft); }
.loop-notes summary:focus-visible { outline-offset: -4px; }
@media (max-width: 1060px) {
  .loop-scroll-help { display: block; }
}
.loop-viewport:focus-visible { outline-offset: -4px; }
.loop-diagram { display: block; width: 100%; min-width: 960px; height: auto; }
.loop-diagram text { fill: var(--ink); stroke: none; text-anchor: middle; font: 15px var(--sans); }
.loop-wires { fill: none; stroke: var(--ink); stroke-width: 1.6; }
.loop-wires rect, .loop-wires circle { fill: var(--surface); }
.loop-diagram marker path { fill: var(--ink); }
.loop-target { stroke-dasharray: 6 4; }
.loop-details { display: grid; grid-template-columns: 1.2fr 1fr; gap: 22px 32px; padding: 22px 24px; }
.loop-details h3 { font-size: 14px; margin-bottom: 8px; }
.loop-details p { color: var(--muted); font-size: 13px; margin-top: 6px; }
.loop-details .loop-equation { color: var(--ink); font-size: 14px; overflow-wrap: anywhere; }
.loop-controller { grid-column: 1 / -1; border-top: 1px solid var(--line-soft); padding-top: 18px; }
@media (max-width: 720px) {
  .loop-details { grid-template-columns: 1fr; padding: 20px; gap: 20px; }
  .control-loop .panel-heading { flex-wrap: wrap; }
}

/* Preserve the compact interactive layout at tablet and phone widths. */
@media (max-width: 1000px) {
  .catalog-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .sim-layout { grid-template-columns: minmax(0, 1fr) 285px; }
  .metrics { grid-template-columns: repeat(2, 1fr); }
  .metrics div:nth-child(2) { border: 0; }
  .metrics div:nth-child(-n+2) { border-bottom: 1px solid var(--line-soft); }
}
@media (max-width: 720px) {
  .intro { padding: 40px 0 24px; align-items: start; flex-direction: column; gap: 24px; }
  .catalog-stats { width: 100%; }
  .catalog-stats div { padding: 16px 18px 14px; }
  .intro-copy { font-size: 15px; }
  .section-top { align-items: start; flex-direction: column; gap: 16px; }
  .search-wrap { width: 100%; min-width: 0; }
  .filter-row { align-items: start; flex-direction: column; gap: 5px; padding: 18px 0 8px; }
  .category-filters { gap: 6px; }
  .category-filters button { padding-inline: 11px; }
  .ready-filter { align-self: flex-end; }
  .results-row > span { display: none; }
  .catalog-grid { gap: 14px; }
  .card-body { padding: 18px; }
  .card-visual { height: 205px; }
  .site-footer { flex-direction: column; }
  .sim-heading { align-items: start; flex-direction: column; gap: 18px; }
  .sim-heading h1 { font-size: 32px; }
  .sim-layout { grid-template-columns: 1fr; }
  .controls { grid-row: 1; }
  .parameter { padding-top: 14px; }
  .controls .control-help, .experiment-tip { display: none; }
  #parameter-controls { display: grid; grid-template-columns: 1fr 1fr; }
  .sim-heading p:last-child { font-size: 14px; }
  .model-notes { padding: 20px; }
}
@media (max-width: 450px) {
  .catalog-grid { grid-template-columns: 1fr; }
  .card-visual { height: 205px; }
  .card-body { padding: 22px; }
  .section-index { font-size: 11px; }
  .parameter { padding-inline: 14px; }
  .parameter label { font-size: 13px; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; animation: none !important; transition: none !important; }
}