:root {
  color-scheme: dark;
  --ink: #e9e5d9;
  --muted: #a8b1ad;
  --ground: #07131a;
  --ground-2: #0d1d24;
  --panel: #10262d;
  --line: rgba(232, 232, 217, .16);
  --amber: #e6ad69;
  --amber-soft: #f3d3a4;
  --mineral: #77bac5;
  --mineral-soft: #bce0df;
  --paper: #f0eadc;
  --paper-ink: #192125;
  --paper-muted: #596366;
  --reading-size: 1.08rem;
  --max: 1180px;
}

:root[data-theme="light"] {
  color-scheme: light;
  --ink: #15242a;
  --muted: #526067;
  --ground: #f1eee5;
  --ground-2: #e4ebe8;
  --panel: #f9f5ea;
  --line: rgba(13, 38, 45, .16);
  --amber: #a95f28;
  --amber-soft: #7e461e;
  --mineral: #287587;
  --mineral-soft: #245f6a;
  --paper: #fffdf7;
  --paper-ink: #192125;
  --paper-muted: #596366;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--ground);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.6;
  text-rendering: optimizeLegibility;
}
a { color: inherit; }
button, input { font: inherit; }
button { color: inherit; }

.skip-link { position: fixed; left: 1rem; top: -5rem; z-index: 100; padding: .7rem 1rem; background: var(--paper); color: var(--paper-ink); }
.skip-link:focus { top: 1rem; }
.reading-progress { position: fixed; inset: 0 0 auto; height: 3px; z-index: 80; background: transparent; }
.reading-progress span { display: block; width: 0; height: 100%; background: linear-gradient(90deg, var(--amber), var(--mineral)); }

.site-header {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; justify-content: space-between;
  gap: 1rem; min-height: 68px; padding: .7rem clamp(1rem, 4vw, 3.2rem);
  background: color-mix(in srgb, var(--ground) 86%, transparent);
  border-bottom: 1px solid var(--line); backdrop-filter: blur(18px);
}
.wordmark { display: inline-flex; align-items: center; gap: .7rem; text-decoration: none; font-size: .78rem; letter-spacing: .16em; font-weight: 700; }
.wordmark-mark { color: var(--amber); font-size: 1.5rem; }
.header-actions { display: flex; align-items: center; gap: clamp(.55rem, 2vw, 1.25rem); }
.header-actions a { color: var(--muted); font-size: .86rem; text-decoration: none; }
.header-actions a:hover { color: var(--ink); }
.icon-button { width: 2.4rem; height: 2.4rem; border-radius: 50%; border: 1px solid var(--line); background: transparent; cursor: pointer; }

.hero { position: relative; min-height: min(820px, calc(100svh - 68px)); overflow: hidden; display: grid; align-items: end; }
.hero > img { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; object-position: center; }
.hero-shade { position: absolute; inset: 0; background: linear-gradient(90deg, rgba(3, 11, 16, .94) 0%, rgba(3, 11, 16, .64) 38%, rgba(3, 11, 16, .12) 68%), linear-gradient(0deg, rgba(3,11,16,.8), transparent 44%); }
.hero-copy { position: relative; z-index: 2; width: min(690px, 92%); padding: clamp(4rem, 10vw, 8.5rem) clamp(1.2rem, 7vw, 6rem); }
.eyebrow { margin: 0 0 1rem; color: var(--amber); font-size: .75rem; letter-spacing: .18em; text-transform: uppercase; font-weight: 700; }
h1, h2, h3 { font-family: Georgia, "Times New Roman", serif; font-weight: 400; line-height: 1.05; }
h1 { margin: 0; font-size: clamp(3.6rem, 8.5vw, 7.8rem); letter-spacing: -.055em; }
h2 { margin: 0; font-size: clamp(2.5rem, 5.8vw, 5rem); letter-spacing: -.045em; }
h3 { font-size: clamp(1.45rem, 2.4vw, 2.1rem); }
.hero-deck { max-width: 560px; margin: 1.6rem 0 .6rem; font: 1.22rem/1.55 Georgia, serif; color: #e8e6dd; }
.byline { color: #c8cbc7; }
.hero-actions { display: flex; flex-wrap: wrap; gap: .75rem; margin-top: 2rem; }
.button { display: inline-flex; justify-content: center; align-items: center; min-height: 46px; padding: .7rem 1.1rem; border-radius: 999px; border: 1px solid var(--line); text-decoration: none; cursor: pointer; }
.button-primary { background: var(--ink); border-color: var(--ink); color: var(--ground); }
.button-secondary { background: rgba(5, 15, 20, .48); color: #f0ede4; border-color: rgba(255,255,255,.3); }
.button-quiet { background: transparent; color: var(--muted); }
.hero-caption { position: absolute; z-index: 2; right: clamp(1.2rem, 4vw, 3rem); bottom: 1.5rem; max-width: 340px; color: #c9ceca; font-size: .8rem; text-align: right; }

.section-wrap { width: min(var(--max), calc(100% - 2.4rem)); margin-inline: auto; }
.threshold { padding-block: clamp(5rem, 11vw, 9rem); }
.threshold > div:first-child { display: grid; grid-template-columns: 1fr 2fr; align-items: end; margin-bottom: 4rem; }
.threshold-grid { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.threshold-grid article { padding: 2rem clamp(1rem, 2.5vw, 2.2rem) 2.4rem; border-right: 1px solid var(--line); }
.threshold-grid article:last-child { border-right: 0; }
.threshold-grid h3 { margin: 1.2rem 0 .8rem; }
.threshold-grid p { color: var(--muted); }
.role-token { display: grid; place-items: center; width: 3rem; height: 3rem; border-radius: 50%; border: 1px solid currentColor; font-weight: 800; font-size: .78rem; }
.role-bi { color: var(--amber); }.role-mi { color: var(--mineral); }.role-third { color: var(--ink); }
.editorial-note { display: grid; grid-template-columns: 1fr 3fr; gap: 2rem; margin-top: 2rem; padding: 1.2rem 0; border-bottom: 1px solid var(--line); color: var(--muted); }
.editorial-note strong { color: var(--ink); }.editorial-note p { margin: 0; }

.field-guide { padding-block: clamp(5rem, 10vw, 9rem); background: var(--ground-2); }
.concept-grid { display: grid; gap: 1.2rem; margin-top: 3rem; }
.concept-card { display: grid; grid-template-columns: minmax(280px, .9fr) minmax(320px, 1.1fr); min-height: 520px; background: var(--panel); border: 1px solid var(--line); overflow: hidden; }
.concept-copy { align-self: center; padding: clamp(1.5rem, 5vw, 4.2rem); }
.concept-copy > p:not(.concept-number):not(.space-detail) { color: var(--muted); }
.concept-number { color: var(--amber); font-size: .72rem; letter-spacing: .16em; }
.concept-copy label { display: block; margin-top: 2rem; font-size: .78rem; color: var(--muted); }
.concept-copy input[type="range"] { width: 100%; accent-color: var(--amber); }
.concept-copy output { display: block; color: var(--amber-soft); font-size: .82rem; }
.spring-simulator {
  --diagram-ink: var(--ink);
  --diagram-muted: var(--muted);
  --diagram-line: var(--line);
  --diagram-amber: var(--amber);
  --diagram-mineral: var(--mineral);
  min-width: 0;
}
.spring-simulator-field { align-self: stretch; display: grid; align-content: center; gap: .4rem; padding: clamp(1.2rem, 3vw, 2.5rem); background: color-mix(in srgb, var(--ground) 38%, transparent); }
.spring-control { display: grid; gap: .45rem; }
.spring-control label { display: flex; justify-content: space-between; gap: 1rem; align-items: baseline; color: var(--diagram-ink); font-size: .82rem; }
.spring-control label span { color: var(--diagram-muted); font-size: .72rem; text-align: right; }
.spring-control input { width: 100%; accent-color: var(--diagram-amber); }
.spring-control output { color: var(--diagram-amber); font-size: .76rem; }
.spring-visual { display: block; width: min(100%, 590px); height: auto; margin-inline: auto; overflow: visible; color: var(--diagram-ink); }
.spring-coil { fill: none; stroke-width: 5; stroke-linecap: round; stroke-linejoin: round; }
.spring-axis, .spring-axis-arrow { fill: none; stroke: var(--diagram-line); stroke-width: 1.4; }
.spring-axis-label, .spring-legend text, .cycle-bracket text { fill: var(--diagram-muted); font: 12px Inter, sans-serif; }
.birth-dot { fill: var(--diagram-mineral); }.contract-dot { fill: var(--diagram-amber); }
.spring-collision { transition: opacity .25s; pointer-events: none; }
.spring-collision ellipse { fill: color-mix(in srgb, var(--diagram-amber) 62%, transparent); }
.spring-collision text { fill: var(--diagram-ink); font: 700 13px Inter, sans-serif; letter-spacing: .04em; }
.cycle-bracket path { fill: none; stroke: var(--diagram-amber); stroke-width: 1.5; }
.cycle-bracket text { dominant-baseline: middle; }
.spring-reading { min-height: 2.7em; margin: 0; color: var(--diagram-muted); font-size: .78rem; }
.space-controls { display: flex; flex-wrap: wrap; gap: .45rem; margin: 1.7rem 0 1rem; }
.space-controls button, .reader-tool-row button { border: 1px solid var(--line); background: transparent; border-radius: 999px; padding: .55rem .75rem; cursor: pointer; }
.space-controls button.active { background: var(--ink); color: var(--ground); }
.space-detail { min-height: 4.5em; }
.spaces-visual { position: relative; min-height: 480px; overflow: hidden; }
.space-orb { position: absolute; top: 14%; width: 62%; aspect-ratio: 1; border-radius: 50%; display: grid; place-items: center; transition: opacity .35s, transform .5s; }
.space-orb span { max-width: 8rem; text-align: center; text-transform: uppercase; letter-spacing: .12em; font-size: .72rem; line-height: 1.8; }
.orb-bi { left: 2%; background: color-mix(in srgb, var(--amber) 32%, transparent); border: 1px solid color-mix(in srgb, var(--amber) 66%, transparent); }
.orb-mi { right: 2%; background: color-mix(in srgb, var(--mineral) 30%, transparent); border: 1px solid color-mix(in srgb, var(--mineral) 66%, transparent); }
.space-core { position: absolute; left: 50%; top: 50%; translate: -50% -50%; z-index: 2; width: 8.5rem; aspect-ratio: 1; display: grid; place-items: center; border-radius: 50%; background: var(--ink); color: var(--ground); text-transform: uppercase; letter-spacing: .12em; font-size: .72rem; transition: transform .4s; }
.spaces-visual[data-active="bi"] .orb-mi { opacity: .35; transform: translateX(14%); }
.spaces-visual[data-active="mi"] .orb-bi { opacity: .35; transform: translateX(-14%); }
.spaces-visual[data-active="third"] .space-core { transform: scale(1.08); }
.cadence-card { grid-template-columns: minmax(280px, .85fr) minmax(360px, 1.15fr); }
.cadence-status { display: grid; grid-template-columns: 1fr auto; gap: .2rem 1rem; align-items: baseline; margin: 1.8rem 0 1rem; }
.cadence-status strong { font: 3.4rem/1 Georgia, serif; }.cadence-status span:last-child { grid-column: 1 / -1; color: var(--muted); font-size: .82rem; }
.timer-actions { display: flex; flex-wrap: wrap; gap: .45rem; }
.cadence-visual { align-self: center; padding: clamp(1.5rem, 5vw, 4rem); }
.cadence-bar { display: flex; height: 240px; align-items: end; gap: .55rem; }
.cadence-bar span { flex-basis: var(--share); height: var(--share); min-height: 95px; padding: 1rem; background: color-mix(in srgb, var(--amber) 22%, transparent); border-top: 1px solid var(--amber); display: flex; flex-direction: column; justify-content: space-between; font-size: .78rem; }
.cadence-bar span:nth-child(2) { background: color-mix(in srgb, var(--mineral) 20%, transparent); border-color: var(--mineral); }
.cadence-bar span:nth-child(3) { background: color-mix(in srgb, var(--ink) 10%, transparent); border-color: var(--ink); }
.cadence-bar b { font: 3rem/1 Georgia, serif; }.rest-line { margin-top: 1rem; color: var(--muted); }

.practice { display: grid; grid-template-columns: .8fr 1.2fr; gap: clamp(2rem, 6vw, 6rem); align-items: center; padding-block: clamp(5rem, 11vw, 9rem); }
.practice-copy p:not(.eyebrow) { color: var(--muted); max-width: 560px; }.copy-status { margin-left: .7rem; color: var(--mineral-soft); font-size: .82rem; }
.capture-card { background: var(--paper); color: var(--paper-ink); padding: clamp(1.25rem, 4vw, 2.6rem); transform: rotate(1deg); box-shadow: 0 28px 70px rgba(0,0,0,.24); }
.capture-card-head { display: flex; justify-content: space-between; border-bottom: 2px solid var(--paper-ink); padding-bottom: .75rem; font-size: .74rem; letter-spacing: .14em; font-weight: 800; }
.capture-card dl { margin: 0; }.capture-card dl div { display: grid; grid-template-columns: 1fr 2fr; gap: 1rem; padding: .85rem 0; border-bottom: 1px solid rgba(25,33,37,.18); }
.capture-card dt { font-weight: 800; }.capture-card dd { margin: 0; color: var(--paper-muted); }

.book-section { background: var(--paper); color: var(--paper-ink); padding-top: clamp(5rem, 10vw, 8rem); }
.book-heading { display: grid; grid-template-columns: 1.4fr .6fr; gap: 3rem; align-items: end; padding-bottom: 3rem; border-bottom: 1px solid rgba(25,33,37,.16); }
.book-heading .eyebrow { color: #9c5828; }.book-heading > div:first-child > p:last-child { color: var(--paper-muted); }
.edition-switch { display: inline-flex; flex-wrap: wrap; gap: .35rem; margin-top: 1.3rem; padding: .3rem; background: #e3dccd; border-radius: 999px; }
.edition-switch button { padding: .55rem .85rem; color: var(--paper-muted); background: transparent; border: 0; border-radius: 999px; cursor: pointer; }
.edition-switch button[aria-pressed="true"] { color: var(--paper); background: var(--paper-ink); }
.reader-tools { display: grid; gap: .55rem; }.reader-tools label { font-size: .75rem; font-weight: 800; text-transform: uppercase; letter-spacing: .1em; }
.reader-tools input { width: 100%; padding: .8rem .9rem; color: var(--paper-ink); background: transparent; border: 1px solid rgba(25,33,37,.26); border-radius: 0; }
.reader-tool-row { display: flex; gap: .4rem; }.reader-tool-row button { color: var(--paper-ink); border-color: rgba(25,33,37,.24); }
.reader-layout { width: min(var(--max), calc(100% - 2.4rem)); margin-inline: auto; display: grid; grid-template-columns: 250px minmax(0, 760px); gap: clamp(2rem, 7vw, 7rem); justify-content: center; }
.book-nav { position: sticky; top: 92px; align-self: start; max-height: calc(100vh - 110px); overflow-y: auto; padding: 2.4rem 0; }
.book-nav-title { font-size: .72rem; letter-spacing: .14em; text-transform: uppercase; font-weight: 800; }
.book-nav nav { display: grid; }.book-nav nav a { padding: .55rem 0; color: var(--paper-muted); border-bottom: 1px solid rgba(25,33,37,.1); text-decoration: none; font-size: .84rem; }
.book-nav nav a.active { color: #9c5828; font-weight: 800; }
.download-panel { display: grid; margin-top: 1.5rem; padding: 1rem; color: var(--paper-ink); background: #e3dccd; text-decoration: none; }.download-panel span { color: var(--paper-muted); font-size: .76rem; }
.source-link { display: inline-block; margin-top: 1rem; color: var(--paper-muted); font-size: .76rem; }
.book-content { min-height: 80vh; padding: 3rem 0 8rem; font-family: Georgia, "Times New Roman", serif; font-size: var(--reading-size); line-height: 1.76; }
.book-nav, .book-content { min-width: 0; }
.book-content { overflow-wrap: anywhere; }
.book-chapter { scroll-margin-top: 95px; }.book-chapter + .book-chapter { margin-top: 7rem; }
.chapter-kicker { color: #9c5828; font: 700 .72rem/1.2 Inter, sans-serif; letter-spacing: .14em; text-transform: uppercase; }
.book-chapter > h2 { color: var(--paper-ink); font-size: clamp(2.8rem, 5vw, 4.8rem); }.chapter-subtitle { color: var(--paper-muted); margin-bottom: 3.2rem; font-style: italic; }
.source-page { scroll-margin-top: 95px; }.source-page + .source-page { margin-top: 3.3rem; padding-top: 3rem; border-top: 1px solid rgba(25,33,37,.13); }
.page-marker { color: #8a8072; font: 700 .68rem/1 Inter, sans-serif; letter-spacing: .12em; text-transform: uppercase; }
.source-page h3 { color: var(--paper-ink); font-size: 1.9em; margin: 1rem 0 1.2rem; }.source-page h4 { font: 800 .8rem/1.35 Inter, sans-serif; letter-spacing: .08em; text-transform: uppercase; color: #8b4d23; margin: 2rem 0 .8rem; }
.source-page p { margin: 0 0 1.2em; }.source-page ul { padding-left: 1.2rem; }.source-page li { margin: .45rem 0; }
.source-page mark { background: #f2c989; color: inherit; padding: 0 .08em; }
.no-results { padding: 4rem 0; color: var(--paper-muted); }
.glossary-term { display: inline; margin: 0; padding: 0 .06em; color: inherit; background: transparent; border: 0; border-bottom: 1px dotted #9c5828; border-radius: 0; font: inherit; line-height: inherit; cursor: help; }
.glossary-term:hover, .glossary-term[aria-expanded="true"] { color: #8b4d23; background: rgba(169,95,40,.09); }
.glossary-popover { position: fixed; z-index: 200; width: min(330px, calc(100vw - 24px)); padding: .9rem 1rem; color: var(--paper-ink); background: var(--paper); border: 1px solid rgba(25,33,37,.22); box-shadow: 0 18px 48px rgba(0,0,0,.22); font-family: Inter, ui-sans-serif, sans-serif; pointer-events: none; }
.glossary-popover[hidden] { display: none; }
.glossary-popover strong { display: block; margin-bottom: .28rem; color: #8b4d23; font-size: .72rem; letter-spacing: .08em; text-transform: uppercase; }
.glossary-popover span { display: block; font-size: .82rem; line-height: 1.5; }
.dual-protocol { margin: 2.8rem 0; padding: 1.2rem; background: #e7e1d4; border-left: 4px solid #9c5828; font-family: Inter, ui-sans-serif, sans-serif; }
.book-content > .dual-protocol { margin-top: 0; margin-bottom: 5rem; }
.dual-protocol-title { margin: 0 0 1rem !important; color: #7d4928; font: 800 .7rem/1.3 Inter, sans-serif; letter-spacing: .14em; text-transform: uppercase; }
.dual-protocol-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1px; background: rgba(25,33,37,.14); }
.dual-protocol-grid section { padding: 1rem; background: #f0eadc; }
.dual-protocol-grid section.protocol-shared { grid-column: 1 / -1; }
.dual-protocol-grid span { display: inline-block; margin-bottom: .45rem; color: #7d4928; font-size: .66rem; font-weight: 800; letter-spacing: .12em; text-transform: uppercase; }
.dual-protocol-grid .protocol-mi span { color: #266b78; }
.dual-protocol-grid p { margin: 0; color: var(--paper-ink); font-size: .82rem; line-height: 1.58; }

.book-diagram {
  --diagram-ink: var(--paper-ink);
  --diagram-muted: var(--paper-muted);
  --diagram-line: rgba(25,33,37,.18);
  --diagram-amber: #a95f28;
  --diagram-mineral: #287587;
  margin: 2.6rem 0 3.2rem;
  padding: 1.4rem 0;
  border-top: 1px solid var(--diagram-line);
  border-bottom: 1px solid var(--diagram-line);
  font-family: Inter, ui-sans-serif, sans-serif;
}
.book-diagram figcaption { display: flex; justify-content: space-between; align-items: baseline; gap: 1.5rem; margin-bottom: 1.4rem; }
.book-diagram figcaption strong { font: 700 .78rem/1.4 Inter, sans-serif; letter-spacing: .08em; text-transform: uppercase; }
.book-diagram figcaption span { color: var(--diagram-muted); font-size: .75rem; text-align: right; }
.phase-state-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.1rem; }
.phase-state-grid > div { display: grid; gap: .3rem; min-width: 0; }
.phase-state-grid svg { width: 100%; background: rgba(25,33,37,.035); }
.phase-state-grid path { fill: none; stroke: var(--diagram-ink); stroke-width: 3; stroke-linecap: round; }
.phase-state-grid circle { fill: color-mix(in srgb, var(--diagram-amber) 28%, transparent); stroke: var(--diagram-amber); stroke-width: 2; }
.phase-state-grid strong { font-size: .78rem; }.phase-state-grid span { color: var(--diagram-muted); font-size: .72rem; line-height: 1.45; }
.method-flow-row { display: grid; grid-template-columns: 1fr auto 1fr auto 1fr; align-items: center; gap: .7rem; }
.method-flow-row > div { display: grid; gap: .25rem; padding: 1rem; border-top: 3px solid var(--diagram-amber); background: rgba(25,33,37,.04); }
.method-flow-row > div:nth-of-type(2) { border-color: var(--diagram-mineral); }.method-flow-row > div:nth-of-type(3) { border-color: var(--diagram-ink); }
.method-flow-row b { font-size: .72rem; letter-spacing: .08em; }.method-flow-row span { font: 1.1rem Georgia, serif; }.method-flow-row small { color: var(--diagram-muted); }
.method-flow-row i { color: var(--diagram-muted); font-style: normal; }
.cadence-inline > div { display: flex; align-items: stretch; gap: .35rem; }
.cadence-inline > div span { flex: var(--part, 3); display: flex; min-width: 0; min-height: 8rem; flex-direction: column; justify-content: space-between; padding: .8rem; background: color-mix(in srgb, var(--diagram-amber) 15%, transparent); border-top: 3px solid var(--diagram-amber); font-size: .72rem; }
.cadence-inline > div span:nth-child(2) { background: color-mix(in srgb, var(--diagram-mineral) 14%, transparent); border-color: var(--diagram-mineral); }
.cadence-inline > div span:nth-child(3) { background: rgba(25,33,37,.06); border-color: var(--diagram-ink); }
.cadence-inline > div span.sleep { flex: 2.2; background: transparent; border-color: var(--diagram-muted); }
.cadence-inline b { font: 2.1rem/1 Georgia, serif; }

body.focus-mode .site-header, body.focus-mode main > :not(.book-section), body.focus-mode footer, body.focus-mode .book-heading, body.focus-mode .book-nav { display: none; }
body.focus-mode .book-section { padding-top: 0; }
body.focus-mode .reader-layout { display: block; max-width: 760px; }

footer { width: min(var(--max), calc(100% - 2.4rem)); margin-inline: auto; padding: 4rem 0; display: grid; grid-template-columns: 1fr 1fr auto; gap: 2rem; color: var(--muted); font-size: .82rem; }
footer p { margin: 0; }

.reveal { opacity: 0; transform: translateY(22px); transition: opacity .7s ease, transform .7s ease; }
.reveal.is-visible { opacity: 1; transform: none; }

@media (max-width: 820px) {
  .header-actions a:nth-child(1), .header-actions a:nth-child(2) { display: none; }
  .hero { min-height: 760px; }.hero-shade { background: linear-gradient(0deg, rgba(3,11,16,.95) 0%, rgba(3,11,16,.62) 62%, rgba(3,11,16,.18)); }.hero-copy { padding-bottom: 7rem; }.hero-caption { display: none; }
  .threshold > div:first-child, .editorial-note, .practice, .book-heading { grid-template-columns: 1fr; }
  .threshold-grid { grid-template-columns: 1fr; }.threshold-grid article { border-right: 0; border-bottom: 1px solid var(--line); }
  .concept-card, .cadence-card { grid-template-columns: 1fr; }.concept-card { min-height: 0; }.spring-simulator-field { padding-bottom: 2rem; }.spaces-visual { min-height: 390px; }
  .practice { gap: 3rem; }.capture-card { transform: none; }
  .reader-layout { grid-template-columns: minmax(0, 1fr); }.book-nav { position: relative; top: auto; max-height: none; overflow: visible; padding-bottom: 0; }.book-nav nav { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 1rem; }
  footer { grid-template-columns: 1fr; }
}

@media (max-width: 520px) {
  .site-header { min-height: 60px; }.header-actions a { display: none; }
  h1 { font-size: clamp(3.2rem, 17vw, 5.4rem); }.hero-copy { width: 100%; }.hero-actions { align-items: stretch; flex-direction: column; }
  .threshold-grid article { padding-inline: 0; }.concept-copy { padding: 1.4rem; }.spaces-visual { min-height: 310px; }.space-orb { width: 72%; }.space-core { width: 6.5rem; }
  .cadence-visual { padding: 1.4rem; }.cadence-bar { height: 190px; }.cadence-bar span { padding: .6rem; font-size: .68rem; }.cadence-bar b { font-size: 2rem; }
  .capture-card dl div { grid-template-columns: 1fr; gap: .2rem; }.book-nav nav { grid-template-columns: 1fr; }
  .book-content { font-size: calc(var(--reading-size) * .96); }.book-chapter > h2 { font-size: 2.7rem; }
  .spring-control label, .book-diagram figcaption { align-items: flex-start; flex-direction: column; gap: .25rem; }.spring-control label span, .book-diagram figcaption span { text-align: left; }
  .phase-state-grid { grid-template-columns: 1fr; }.phase-state-grid > div { grid-template-columns: 120px 1fr; align-items: center; }.phase-state-grid > div span { grid-column: 2; }.phase-state-grid svg { grid-row: 1 / span 2; }
  .method-flow-row { grid-template-columns: 1fr; }.method-flow-row i { text-align: center; transform: rotate(90deg); }
  .cadence-inline > div { display: grid; grid-template-columns: 1fr 1fr; }.cadence-inline > div span { min-height: 6rem; }
  .dual-protocol-grid { grid-template-columns: 1fr; }.dual-protocol-grid section.protocol-shared { grid-column: auto; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }.reveal { opacity: 1; transform: none; transition: none; } * { animation: none !important; transition-duration: .01ms !important; }
}