*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --article-width: 780px;
  --wide-width: 1040px;
  --body-font: 'Source Serif 4', Georgia, serif;
  --heading-font: 'Source Sans 3', system-ui, sans-serif;
  --mono-font: 'Source Code Pro', monospace;
  --body-size: 1.125rem;
  --line-height: 1.65;
  --text: #1b1d2a;
  --text-2: #565a68;
  --muted: #858998;
  --accent: #8a4b23;
  --accent-light: #f1e7df;
  --bg: #fafafa;
  --fig-bg: #ffffff;
  --paper: #f5f6f3;
  --border: #dedfd8;
  --border-2: #c5c8be;
  --c-physical: #c46f2f;
  --c-internal: #1f7a8c;
  --c-window: #78a66f;
  --c-boundary: #b44a3f;
  --c-lattice: #353947;
  --c-ghost: #c9cbc5;
  --c-gold: #b9942f;
  --c-violet: #6e5ca8;
}

body {
  font-family: var(--body-font);
  font-size: var(--body-size);
  line-height: var(--line-height);
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

.article {
  max-width: var(--article-width);
  margin: 0 auto;
  padding: 2rem 1.25rem 6rem;
}

h1, h2, h3 {
  font-family: var(--heading-font);
  font-weight: 700;
  line-height: 1.18;
}

h1 { font-size: 2.45rem; margin: 0 0 0.6rem; letter-spacing: 0; }
h2 { font-size: 1.36rem; margin: 2.8rem 0 0.7rem; }
h3 { font-size: 1.05rem; margin: 1.5rem 0 0.45rem; }
p { margin: 0 0 1rem; }
a { color: var(--accent); text-decoration: underline; text-underline-offset: 2px; }
a:hover { color: #6f3919; }
a:focus-visible,
button:focus-visible,
input:focus-visible {
  outline: 2px solid var(--c-internal);
  outline-offset: 3px;
}

code {
  font-family: var(--mono-font);
  font-size: 0.88em;
  background: #eceee8;
  padding: 0.08em 0.28em;
  border-radius: 3px;
}

.back-links {
  font-family: var(--heading-font);
  font-size: 0.84rem;
  margin-bottom: 2rem;
}

.back-links a { color: var(--text-2); text-decoration: none; }
.back-links a:hover { color: var(--accent); }
.back-links .sep { margin: 0 0.45rem; color: var(--border-2); }

header { margin-bottom: 2rem; }
.eyebrow {
  font-family: var(--mono-font);
  color: var(--muted);
  font-size: 0.78rem;
  margin-bottom: 0.55rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.subtitle {
  font-family: var(--heading-font);
  font-size: 1.08rem;
  color: var(--text-2);
  max-width: 660px;
}

.series-mark {
  margin: 1.4rem 0 2.2rem;
  border: 1px solid var(--border);
  background: var(--fig-bg);
  border-radius: 6px;
  padding: 1rem;
}

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

.section-kicker {
  font-family: var(--mono-font);
  color: var(--muted);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-top: 2.4rem;
  margin-bottom: 0.2rem;
}

.figure {
  margin: 1.7rem 0 2rem;
  padding: 1rem;
  background: var(--fig-bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow-x: auto;
  overflow-y: hidden;
}

.figure-wide {
  width: min(var(--wide-width), calc(100vw - 2rem));
  margin-left: 50%;
  transform: translateX(-50%);
}

.figure-caption {
  font-family: var(--heading-font);
  color: var(--text-2);
  font-size: 0.84rem;
  line-height: 1.45;
  margin-top: 0.75rem;
}

.figure-label { color: var(--text); font-weight: 700; }

.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem 1rem;
  align-items: center;
  margin: 0 0 0.8rem;
  font-family: var(--heading-font);
  color: var(--text-2);
  font-size: 0.84rem;
}

.controls label {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  min-width: max-content;
}

.controls input[type="range"] {
  width: 145px;
  accent-color: var(--accent);
}

.controls button,
.segmented button {
  font-family: var(--heading-font);
  font-weight: 700;
  font-size: 0.82rem;
  border: 1px solid var(--border-2);
  background: var(--fig-bg);
  color: var(--text);
  border-radius: 4px;
  padding: 0.38rem 0.7rem;
  cursor: pointer;
}

.controls button:hover,
.segmented button:hover { border-color: var(--accent); color: var(--accent); }
.controls button.active,
.segmented button.active { background: var(--accent); border-color: var(--accent); color: #fff; }

.value {
  font-family: var(--mono-font);
  font-size: 0.8rem;
  color: var(--text);
  min-width: 3.5em;
  display: inline-block;
}

.definition-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0.7rem;
  margin: 1rem 0;
}

.definition-tile {
  border: 1px solid var(--border);
  border-radius: 5px;
  background: #fbfbf8;
  padding: 0.85rem;
  min-height: 8.5rem;
}

.definition-tile h3 {
  font-size: 0.9rem;
  margin: 0 0 0.35rem;
}

.definition-tile p {
  font-family: var(--heading-font);
  font-size: 0.8rem;
  line-height: 1.45;
  color: var(--text-2);
  margin: 0;
}

.next-prev {
  margin-top: 3.5rem;
  padding-top: 1.4rem;
  border-top: 1px solid var(--border);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  font-family: var(--heading-font);
}

.next-prev a {
  text-decoration: none;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 0.85rem 1rem;
  background: var(--fig-bg);
}

.next-prev a:hover { border-color: var(--accent); color: var(--accent); }
.next-prev .label {
  display: block;
  color: var(--muted);
  font-family: var(--mono-font);
  font-size: 0.72rem;
  margin-bottom: 0.25rem;
  text-transform: uppercase;
}

.footer {
  margin-top: 2.8rem;
  padding-top: 1.4rem;
  border-top: 1px solid var(--border);
  font-family: var(--heading-font);
  font-size: 0.84rem;
  color: var(--text-2);
}

.card-list {
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
  margin: 1.5rem 0 2rem;
}

.card {
  display: grid;
  grid-template-columns: 5rem 1fr;
  gap: 1rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 1rem;
  background: var(--fig-bg);
  color: var(--text);
  text-decoration: none;
  transition: border-color 0.15s, transform 0.15s;
}

.card:hover { border-color: var(--accent); transform: translateY(-1px); }
.card-thumb { width: 5rem; height: 5rem; border: 1px solid #eceee8; border-radius: 4px; overflow: hidden; background: var(--paper); }
.card-title { font-family: var(--heading-font); font-size: 1.06rem; font-weight: 700; margin-bottom: 0.25rem; }
.card-number { font-family: var(--mono-font); color: var(--muted); font-size: 0.75rem; margin-bottom: 0.2rem; }
.card-desc { font-size: 0.91rem; color: var(--text-2); line-height: 1.45; margin: 0; }
.card-tags { font-family: var(--heading-font); color: var(--accent); font-size: 0.73rem; margin-top: 0.4rem; }

.act-heading {
  margin-top: 2.6rem;
  font-family: var(--heading-font);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-2);
  font-size: 0.78rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 0.8rem;
}

.act-heading::after { content: ""; flex: 1; height: 1px; background: var(--border); }

svg text { font-family: var(--heading-font); }
canvas { display: block; width: 100%; }
.t-physical { color: var(--c-physical); font-weight: 700; }
.t-internal { color: var(--c-internal); font-weight: 700; }
.t-window { color: var(--c-window); font-weight: 700; }
.t-gold { color: var(--c-gold); font-weight: 700; }

@media (max-width: 720px) {
  h1 { font-size: 1.85rem; }
  .article { padding: 1.35rem 1rem 4rem; }
  .definition-row { grid-template-columns: 1fr; }
  .definition-tile { min-height: 0; }
  .card { grid-template-columns: 3.8rem 1fr; padding: 0.85rem; }
  .card-thumb { width: 3.8rem; height: 3.8rem; }
  .next-prev { grid-template-columns: 1fr; }
  .figure-wide { width: 100%; margin-left: 0; transform: none; }
  .figure svg,
  .figure canvas { min-width: 720px; }
}

@media (prefers-reduced-motion: reduce) {
  html:not([data-motion="full"]) *,
  html:not([data-motion="full"]) *::before,
  html:not([data-motion="full"]) *::after {
    animation-duration: 0s !important;
    transition-duration: 0s !important;
  }
}