:root {
  --paper: #f4f3ed;
  --paper-bright: #fbfaf6;
  --ink: #171716;
  --muted: #6c6d66;
  --line: #d8d8cf;
  --accent: #6457e8;
  --accent-soft: #e9e6ff;
  --green: #335f4a;
  --dark: #1d1d1b;
  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  --sans: "Avenir Next", Avenir, "Helvetica Neue", Helvetica, Arial, sans-serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --max-width: 1180px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration-thickness: 1px; text-underline-offset: 0.2em; }
button, input, select { font: inherit; }
.skip-link {
  position: fixed;
  left: 1rem;
  top: -6rem;
  z-index: 20;
  background: var(--ink);
  color: #fff;
  padding: 0.75rem 1rem;
}
.skip-link:focus { top: 1rem; }
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}
.section-shell,
.site-header,
.article-shell,
.note-shell {
  width: min(calc(100% - 3rem), var(--max-width));
  margin-inline: auto;
}
.site-header {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
  border-bottom: 1px solid var(--line);
}
.wordmark {
  display: flex;
  align-items: baseline;
  gap: 0.8rem;
  text-decoration: none;
}
.wordmark span {
  font-family: var(--serif);
  font-size: 1.45rem;
  font-weight: 700;
}
.wordmark small {
  color: var(--muted);
  font-size: 0.7rem;
  letter-spacing: 0.13em;
  text-transform: uppercase;
}
.site-nav { display: flex; align-items: center; gap: 2rem; }
.site-nav a {
  color: #42423f;
  font-size: 0.85rem;
  font-weight: 600;
  text-decoration: none;
}
.site-nav a:hover,
.site-nav a:focus-visible,
.site-nav a[aria-current="page"] { color: var(--accent); }
.menu-button {
  display: none;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: transparent;
  padding: 0.45rem 0.8rem;
}
.hero {
  min-height: 680px;
  display: grid;
  grid-template-columns: minmax(0, 1.65fr) minmax(280px, 0.75fr);
  align-items: center;
  gap: clamp(3rem, 8vw, 7rem);
  padding-block: 6rem;
}
.eyebrow,
.section-index,
.status-label,
.aside-label,
.claim-label {
  margin: 0 0 1.25rem;
  color: var(--accent);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}
.signal-dot {
  display: inline-block;
  width: 0.55rem;
  height: 0.55rem;
  margin-right: 0.45rem;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 5px var(--accent-soft);
}
.hero h1,
.article-hero h1 {
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(4.8rem, 9.5vw, 8.7rem);
  font-weight: 500;
  letter-spacing: -0.065em;
  line-height: 0.82;
}
.hero h1 em,
.article-hero h1 em {
  color: var(--accent);
  font-weight: 500;
}
.hero-deck {
  max-width: 760px;
  margin: 2.4rem 0 0;
  color: #4e4e48;
  font-family: var(--serif);
  font-size: clamp(1.25rem, 2vw, 1.65rem);
  line-height: 1.5;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-top: 2.5rem; }
.button {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--ink);
  border-radius: 3px;
  padding: 0.7rem 1.2rem;
  font-size: 0.82rem;
  font-weight: 700;
  text-decoration: none;
}
.button-dark { background: var(--ink); color: #fff; }
.button-dark:hover,
.button-dark:focus-visible { background: var(--accent); border-color: var(--accent); }
.button-light { background: transparent; }
.button-light:hover,
.button-light:focus-visible { background: var(--paper-bright); }
.status-card {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 4px;
  background: rgba(255,255,255,0.45);
  padding: 1.5rem;
  box-shadow: 18px 18px 0 rgba(100,87,232,0.08);
}
.status-card::before {
  content: "";
  position: absolute;
  width: 170px;
  height: 170px;
  right: -90px;
  top: -95px;
  border: 1px solid var(--accent);
  border-radius: 50%;
}
.status-card__top { display: flex; justify-content: space-between; align-items: flex-start; }
.status-number { color: var(--line); font-family: var(--serif); font-size: 4rem; line-height: 0.8; }
.status-title { margin: 2.5rem 0 0.25rem; font-family: var(--serif); font-size: 2rem; }
.status-copy { color: var(--muted); font-size: 0.9rem; }
.status-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; margin: 2rem 0 0; padding-top: 1rem; border-top: 1px solid var(--line); }
.status-grid div { display: flex; flex-direction: column; }
.status-grid dt { color: var(--muted); font-size: 0.68rem; text-transform: uppercase; letter-spacing: 0.08em; }
.status-grid dd { margin: 0.25rem 0 0; font-family: var(--serif); font-size: 1.2rem; }
.thesis {
  display: grid;
  grid-template-columns: 0.6fr 2fr 0.7fr;
  gap: 3rem;
  align-items: start;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  padding-block: 5rem;
}
.thesis h2,
.section-heading h2,
.about-section h2,
.method-lead h2,
.prose h2 {
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(2.4rem, 5vw, 4.6rem);
  font-weight: 500;
  letter-spacing: -0.045em;
  line-height: 1;
}
.thesis > div > p { max-width: 760px; margin: 2rem 0 0; color: var(--muted); font-size: 1.05rem; }
.margin-note { margin: 0; color: var(--green); font-family: var(--serif); font-style: italic; }
.notes-section { padding-block: 7rem; }
.section-heading { display: grid; grid-template-columns: 1.4fr 0.7fr; gap: 4rem; align-items: end; }
.section-intro { margin: 0 0 0.4rem; color: var(--muted); }
.note-controls {
  display: grid;
  grid-template-columns: minmax(280px, 1fr) 230px auto;
  gap: 0.75rem;
  align-items: center;
  margin-top: 4rem;
  padding: 1rem 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.search-field { display: flex; align-items: center; gap: 0.65rem; }
.search-field input,
.note-controls select {
  width: 100%;
  min-height: 44px;
  border: 1px solid var(--line);
  border-radius: 3px;
  background: var(--paper-bright);
  color: var(--ink);
  padding: 0 0.8rem;
}
.search-field input:focus,
.note-controls select:focus { outline: 2px solid var(--accent); outline-offset: 2px; }
.note-count { margin: 0; color: var(--muted); font-size: 0.75rem; text-align: right; text-transform: uppercase; letter-spacing: 0.08em; }
.note-list { min-height: 240px; }
.note-card {
  display: grid;
  grid-template-columns: 80px minmax(0, 1fr) 180px;
  gap: 2rem;
  align-items: start;
  border-bottom: 1px solid var(--line);
  padding-block: 2.25rem;
}
.note-card__number { color: var(--accent); font-family: var(--serif); font-size: 2rem; }
.note-card__meta { display: flex; flex-wrap: wrap; gap: 1rem; color: var(--muted); font-size: 0.67rem; letter-spacing: 0.08em; text-transform: uppercase; }
.note-card h3 { margin: 0.55rem 0 0.35rem; font-family: var(--serif); font-size: 2rem; font-weight: 500; }
.note-card h3 a { text-decoration: none; }
.note-card h3 a:hover { color: var(--accent); }
.note-card__body > p { margin: 0; color: var(--muted); }
.tag-list { display: flex; flex-wrap: wrap; gap: 0.5rem; margin: 1rem 0 0; padding: 0; list-style: none; }
.tag-list li { border: 1px solid var(--line); border-radius: 999px; padding: 0.25rem 0.65rem; color: #55564f; font-size: 0.67rem; }
.note-card__action { display: flex; min-height: 100%; flex-direction: column; align-items: flex-end; justify-content: space-between; text-align: right; }
.note-card__action span { color: var(--green); font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.08em; }
.note-card__action a { font-size: 0.8rem; font-weight: 700; }
.empty-state { margin: 2rem 0; border: 1px dashed var(--line); padding: 2rem; color: var(--muted); }
.explore-section { padding-block: 7rem; border-top: 1px solid var(--line); }
.surface-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1px; margin-top: 4rem; background: var(--line); border: 1px solid var(--line); }
.surface-card { position: relative; min-height: 310px; background: var(--paper); padding: 2rem; text-decoration: none; }
.surface-card:hover,
.surface-card:focus-visible { background: var(--paper-bright); }
.surface-card__number { color: var(--accent); font-family: var(--mono); font-size: 0.72rem; }
.surface-card__status { position: absolute; top: 2rem; right: 2rem; border: 1px solid var(--line); border-radius: 999px; padding: 0.2rem 0.55rem; color: var(--muted); font-size: 0.62rem; letter-spacing: 0.07em; text-transform: uppercase; }
.surface-card h3 { margin: 4.5rem 0 0.7rem; font-family: var(--serif); font-size: 2rem; font-weight: 500; }
.surface-card p { max-width: 450px; margin: 0; color: var(--muted); }
.surface-card strong { display: block; margin-top: 2rem; color: var(--green); font-size: 0.78rem; }
.research-unit { display: grid; grid-template-columns: 0.8fr 1.5fr; gap: 5rem; align-items: center; margin-top: 6rem; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); padding-block: 5rem; }
.research-unit__lead h3 { margin: 0; font-family: var(--serif); font-size: clamp(2rem, 4vw, 3.2rem); font-weight: 500; letter-spacing: -0.04em; line-height: 1.05; }
.research-unit__lead p:not(.section-index) { color: var(--muted); }
.unit-flow { display: grid; grid-template-columns: repeat(5, 1fr); margin: 0; padding: 0; list-style: none; }
.unit-flow li { position: relative; min-height: 150px; border-left: 1px solid var(--line); padding: 1rem; }
.unit-flow li:last-child { border-right: 1px solid var(--line); }
.unit-flow li::after { content: "→"; position: absolute; right: -0.45rem; top: 50%; z-index: 1; color: var(--accent); background: var(--paper); }
.unit-flow li:last-child::after { display: none; }
.unit-flow span { display: block; color: var(--accent); font-family: var(--mono); font-size: 0.66rem; }
.unit-flow strong { display: block; margin-top: 2.6rem; font-family: var(--serif); font-size: 1.1rem; font-weight: 500; }
.unit-flow small { display: block; margin-top: 0.2rem; color: var(--muted); font-size: 0.68rem; }
.method-section {
  display: grid;
  grid-template-columns: minmax(260px, 0.7fr) 1.5fr;
  gap: 6rem;
  background: var(--dark);
  color: #f4f3ed;
  padding: 6rem max(1.5rem, calc((100vw - var(--max-width)) / 2));
  width: 100%;
  max-width: none;
}
.section-index--light { color: #a99fff; }
.method-lead h2 { color: #fff; }
.method-lead > p:not(.section-index) { color: #aead9f; }
.text-link { font-weight: 700; }
.text-link--light { color: #c8c3ff; }
.method-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 0; margin: 0; padding: 0; list-style: none; border-top: 1px solid #44443e; }
.method-grid li { min-height: 210px; border-bottom: 1px solid #44443e; padding: 1.4rem 1.5rem; }
.method-grid li:nth-child(odd) { border-right: 1px solid #44443e; padding-left: 0; }
.method-grid li span { color: #7e72ff; font-family: var(--mono); font-size: 0.72rem; }
.method-grid h3 { margin: 1.2rem 0 0.4rem; font-family: var(--serif); font-size: 1.6rem; font-weight: 500; }
.method-grid p { margin: 0; color: #aead9f; font-size: 0.9rem; }
.about-section { display: grid; grid-template-columns: 0.8fr 1.4fr; gap: 6rem; padding-block: 7rem; }
.about-columns { display: grid; grid-template-columns: 1fr 1fr; gap: 3rem; }
.about-columns h3 { margin: 0; color: var(--accent); font-size: 0.72rem; letter-spacing: 0.12em; text-transform: uppercase; }
.about-columns ul { margin: 1.2rem 0 0; padding: 0; list-style: none; }
.about-columns li { border-top: 1px solid var(--line); padding: 0.8rem 0; color: #4d4e48; }
.closing { border-top: 1px solid var(--line); padding-block: 6rem; text-align: center; }
.closing-quote { max-width: 900px; margin: 1.5rem auto 2.5rem; font-family: var(--serif); font-size: clamp(2.3rem, 5vw, 4.5rem); letter-spacing: -0.04em; line-height: 1.05; }
.site-footer {
  display: grid;
  grid-template-columns: 1fr auto auto;
  gap: 2rem;
  align-items: center;
  min-height: 130px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.76rem;
}
.site-footer div { display: flex; flex-direction: column; }
.site-footer strong { color: var(--ink); font-family: var(--serif); font-size: 1rem; }
.site-footer p { margin: 0; }

/* Long-form pages */
.article-hero,
.note-hero { max-width: 1020px; padding: 7rem 0 5rem; }
.article-hero h1 { font-size: clamp(4.3rem, 9vw, 8rem); }
.article-hero > p:last-child { max-width: 760px; margin: 2.3rem 0 0; color: var(--muted); font-family: var(--serif); font-size: 1.35rem; }
.article-layout,
.note-layout { display: grid; grid-template-columns: 245px minmax(0, 760px); gap: 6rem; align-items: start; padding-bottom: 8rem; }
.article-aside,
.note-toc { position: sticky; top: 2rem; border-top: 2px solid var(--ink); padding-top: 1rem; }
.claim-key { margin: 0; }
.claim-key div { border-top: 1px solid var(--line); padding: 1rem 0; }
.claim-key dt { color: var(--accent); font-size: 0.7rem; font-weight: 700; letter-spacing: 0.1em; }
.claim-key dd { margin: 0.25rem 0 0; color: var(--muted); font-size: 0.8rem; }
.prose section { padding: 0 0 4rem; margin: 0 0 4rem; border-bottom: 1px solid var(--line); }
.prose h2 { font-size: clamp(2.2rem, 4vw, 3.5rem); }
.prose p { color: #484942; font-family: var(--serif); font-size: 1.15rem; line-height: 1.75; }
.prose blockquote { margin: 2rem 0 0; border-left: 3px solid var(--accent); padding: 0.5rem 0 0.5rem 1.5rem; color: var(--green); font-family: var(--serif); font-size: 1.45rem; font-style: italic; }
.checklist { padding: 0; list-style: none; }
.checklist li { position: relative; border-top: 1px solid var(--line); padding: 0.9rem 0 0.9rem 2.2rem; }
.checklist li::before { content: "□"; position: absolute; left: 0; color: var(--accent); }
.note-hero h1 { max-width: 970px; margin: 2rem 0 0; font-family: var(--serif); font-size: clamp(3.4rem, 7vw, 6.4rem); font-weight: 500; letter-spacing: -0.055em; line-height: 0.95; }
.template-banner { display: flex; justify-content: space-between; gap: 1rem; margin-bottom: 5rem; border: 1px solid var(--accent); background: var(--accent-soft); padding: 0.8rem 1rem; color: #4036a5; font-size: 0.72rem; letter-spacing: 0.08em; text-transform: uppercase; }
.learning-banner { border-color: #4e765d; background: rgba(78, 118, 93, 0.08); color: #365f45; }
.note-abstract { max-width: 780px; margin: 2rem 0 0; color: var(--muted); font-family: var(--serif); font-size: 1.35rem; }
.note-toc { display: flex; flex-direction: column; gap: 0.5rem; }
.note-toc a { color: var(--muted); font-size: 0.82rem; text-decoration: none; }
.note-toc a:hover { color: var(--accent); }
.note-toc .toc ul { margin: 0; padding: 0; list-style: none; }
.note-toc .toc ul ul { margin: 0.35rem 0 0.65rem 0.9rem; }
.note-toc .toc li { margin: 0.25rem 0; }
.markdown-body > h2 { margin-top: 4rem; padding-top: 4rem; border-top: 1px solid var(--line); scroll-margin-top: 2rem; }
.markdown-body > blockquote + h2 { margin-top: 4rem; }
.markdown-body h3 { margin: 2.3rem 0 0.7rem; font-family: var(--serif); font-size: 1.55rem; font-weight: 500; }
.markdown-body ul,
.markdown-body ol { color: #484942; font-family: var(--serif); font-size: 1.08rem; line-height: 1.7; }
.markdown-body li { margin: 0.4rem 0; }
.markdown-body code { border-radius: 3px; background: var(--paper-bright); padding: 0.12rem 0.3rem; font-family: var(--mono); font-size: 0.85em; }
.markdown-body pre { overflow-x: auto; border: 1px solid var(--line); background: var(--paper-bright); padding: 1.2rem; }
.markdown-body pre code { padding: 0; background: transparent; }
.markdown-body mjx-container[jax="SVG"][display="true"] { overflow-x: auto; overflow-y: hidden; margin: 1.5rem 0 !important; padding: 0.4rem 0; }
.markdown-body mjx-container[jax="SVG"][display="true"] > svg { min-width: max-content; }
.markdown-body table { width: 100%; margin: 2rem 0; border-collapse: collapse; font-size: 0.9rem; }
.markdown-body th,
.markdown-body td { border-bottom: 1px solid var(--line); padding: 0.75rem; text-align: left; vertical-align: top; }
.markdown-body img { max-width: 100%; height: auto; }
.claim-label { display: inline-block; border: 1px solid var(--accent); border-radius: 999px; padding: 0.25rem 0.6rem; }
.claim-label--intuition { color: var(--green); border-color: var(--green); }
.claim-label--derivation { color: #9b5d18; border-color: #9b5d18; }
.claim-label--direct { color: #376e75; border-color: #376e75; }
.claim-label--synthesis { color: #7b4d83; border-color: #7b4d83; }
.claim-label--hypothesis { color: #9b3b47; border-color: #9b3b47; }
.placeholder { color: #797a73 !important; }
.figure-placeholder { display: grid; min-height: 280px; place-content: center; margin-top: 2rem; border: 1px dashed #aaa9a0; background: repeating-linear-gradient(-45deg, transparent 0 12px, rgba(100,87,232,0.035) 12px 24px); padding: 2rem; text-align: center; }
.figure-placeholder span { color: var(--accent); font-family: var(--mono); font-size: 0.72rem; letter-spacing: 0.1em; }
.figure-placeholder p { max-width: 440px; font-size: 1rem; }
.equation-placeholder { margin-top: 2rem; border-left: 3px solid #9b5d18; background: var(--paper-bright); padding: 2rem; color: #9b5d18; font-family: var(--serif); font-size: 1.5rem; font-style: italic; text-align: center; }
.evidence-card { margin-top: 2rem; border: 1px solid var(--line); background: var(--paper-bright); padding: 1.5rem; }
.evidence-card > span { color: #376e75; font-size: 0.68rem; font-weight: 700; letter-spacing: 0.1em; }
.evidence-card dl { margin: 1rem 0 0; }
.evidence-card dl div { display: grid; grid-template-columns: 140px 1fr; border-top: 1px solid var(--line); padding: 0.7rem 0; }
.evidence-card dt { color: var(--muted); font-size: 0.75rem; }
.evidence-card dd { margin: 0; font-family: var(--serif); }
.open-question-list { padding-left: 1.4rem; color: var(--muted); font-family: var(--serif); font-size: 1.1rem; }
.open-question-list li { padding: 0.5rem 0; }
.learning-prompts { display: grid; gap: 1px; margin-top: 2rem; border: 1px solid var(--line); background: var(--line); }
.learning-prompts article { display: grid; grid-template-columns: 46px minmax(170px, 0.65fr) minmax(0, 1fr); gap: 1rem; align-items: center; background: var(--paper-bright); padding: 1rem; }
.learning-prompts span { color: var(--accent); font-family: var(--mono); font-size: 0.68rem; }
.learning-prompts h3 { margin: 0; font-family: var(--serif); font-size: 1.2rem; font-weight: 500; }
.learning-prompts p { margin: 0; color: var(--muted); font-family: var(--mono); font-size: 0.68rem; line-height: 1.6; }
.references-placeholder { color: var(--muted); }
.structure-hero { max-width: 1120px; }
.architecture-map { margin-bottom: 8rem; border: 1px solid var(--line); background: var(--paper-bright); padding: 2rem; }
.architecture-map__root { max-width: 560px; margin: 0 auto; border: 1px solid var(--accent); background: var(--accent-soft); padding: 1.5rem; text-align: center; }
.architecture-map__root span,
.architecture-map__branches article > span { color: var(--accent); font-family: var(--mono); font-size: 0.66rem; letter-spacing: 0.1em; }
.architecture-map__root h2 { margin: 0.5rem 0 0; font-family: var(--serif); font-size: 2.4rem; font-weight: 500; }
.architecture-map__root p { margin: 0.25rem 0 0; color: var(--muted); }
.architecture-map__branches { position: relative; display: grid; grid-template-columns: repeat(4, 1fr); gap: 1rem; padding-top: 4rem; }
.architecture-map__branches::before { content: ""; position: absolute; top: 2rem; left: 12.5%; right: 12.5%; border-top: 1px solid var(--line); }
.architecture-map__branches article { position: relative; min-height: 190px; border-top: 2px solid var(--ink); padding: 1rem; }
.architecture-map__branches article::before { content: ""; position: absolute; top: -2rem; left: 50%; height: 2rem; border-left: 1px solid var(--line); }
.architecture-map__branches h3 { margin: 2.4rem 0 0.4rem; font-family: var(--serif); font-size: 1.35rem; font-weight: 500; }
.architecture-map__branches p { margin: 0; color: var(--muted); font-size: 0.82rem; }
.structure-sections { margin-bottom: 4rem; }
.structure-section { display: grid; grid-template-columns: 0.65fr 1.6fr; gap: 4rem; border-top: 1px solid var(--line); padding-block: 5rem; }
.structure-section h2 { margin: 0; font-family: var(--serif); font-size: clamp(2.3rem, 5vw, 4rem); font-weight: 500; letter-spacing: -0.045em; line-height: 1; }
.structure-section div > p:not(.framework-note) { max-width: 720px; color: var(--muted); font-family: var(--serif); font-size: 1.15rem; }
.framework-note { display: inline-block; margin-top: 1.5rem; border: 1px solid var(--line); border-radius: 999px; padding: 0.4rem 0.7rem; color: var(--green); font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.06em; }

@media (max-width: 900px) {
  .hero { grid-template-columns: 1fr; min-height: auto; }
  .status-card { max-width: 500px; }
  .thesis { grid-template-columns: 1fr; }
  .section-heading,
  .method-section,
  .about-section,
  .research-unit { grid-template-columns: 1fr; }
  .section-heading { align-items: start; }
  .note-controls { grid-template-columns: 1fr 1fr; }
  .note-count { grid-column: 1 / -1; text-align: left; }
  .article-layout,
  .note-layout { grid-template-columns: 1fr; gap: 3rem; }
  .article-aside,
  .note-toc { position: static; }
  .site-footer { grid-template-columns: 1fr 1fr; }
  .site-footer p { display: none; }
  .unit-flow { grid-template-columns: repeat(5, minmax(125px, 1fr)); overflow-x: auto; padding-bottom: 1rem; }
  .architecture-map__branches { grid-template-columns: repeat(2, 1fr); }
  .architecture-map__branches::before,
  .architecture-map__branches article::before { display: none; }
}

@media (max-width: 640px) {
  .section-shell,
  .site-header,
  .article-shell,
  .note-shell { width: min(calc(100% - 2rem), var(--max-width)); }
  .site-header { position: relative; min-height: 68px; }
  .wordmark small { display: none; }
  .menu-button { display: block; }
  .site-nav {
    display: none;
    position: absolute;
    z-index: 10;
    top: 62px;
    right: 0;
    min-width: 190px;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    border: 1px solid var(--line);
    background: var(--paper-bright);
    padding: 0.5rem;
  }
  .site-nav.is-open { display: flex; }
  .site-nav a { padding: 0.65rem; }
  .hero { padding-block: 4.5rem; gap: 3.5rem; }
  .hero h1,
  .article-hero h1 { font-size: clamp(3.1rem, 15vw, 4.8rem); }
  .hero-actions { flex-direction: column; align-items: stretch; }
  .hero-actions .button { width: 100%; }
  .hero-deck { font-size: 1.15rem; }
  .thesis,
  .notes-section,
  .about-section { padding-block: 5rem; }
  .section-heading { gap: 2rem; }
  .note-controls { grid-template-columns: 1fr; }
  .note-card { grid-template-columns: 44px 1fr; gap: 1rem; }
  .note-card__action { grid-column: 2; min-height: 0; flex-direction: row; align-items: center; text-align: left; }
  .method-section { gap: 3rem; padding-block: 5rem; }
  .method-grid { grid-template-columns: 1fr; }
  .method-grid li:nth-child(odd) { border-right: 0; padding-left: 1.5rem; }
  .about-columns { grid-template-columns: 1fr; }
  .surface-grid { grid-template-columns: 1fr; }
  .surface-card { min-height: 270px; }
  .architecture-map { padding: 1rem; }
  .architecture-map__branches { grid-template-columns: 1fr; padding-top: 1rem; }
  .structure-section { grid-template-columns: 1fr; gap: 1rem; padding-block: 4rem; }
  .article-hero,
  .note-hero { padding-block: 5rem 3rem; }
  .template-banner { flex-direction: column; margin-bottom: 3rem; }
  .evidence-card dl div { grid-template-columns: 1fr; gap: 0.25rem; }
  .learning-prompts article { grid-template-columns: 34px 1fr; }
  .learning-prompts p { grid-column: 2; }
  .site-footer { grid-template-columns: 1fr; gap: 0.6rem; padding-block: 2rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; transition-duration: 0.01ms !important; }
}