/* Stickwise course textbook (F22, 6 October 2026). Studio palette (cobalt #4540EB, lime #C7F56B), Space Grotesk
   headings, DM Sans controls. Long reading uses Atkinson Hyperlegible Next, designed by the Braille Institute so that
   easily confused characters stay distinct (I l 1, O 0, b d p q), which matters in science and maths notation such
   as Cl, I for current and O2; DM Sans stays the fallback. textbook.js loads the font only when a textbook is opened. Figures use [claude-diagrams]' --sw-figure-max-h when it
   is defined, so a figure is never taller than the screen. */
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/* ---------- chapter opener ---------- */
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/* ---------- layout, contents and running head ---------- */
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/* ---------- the page ---------- */
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/* ---------- figures ---------- */
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/* ---------- boxes ---------- */
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/* ---------- labels for tiers and routes ---------- */
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.tb-point.is-excluded .tb-code{background:#6b6a7d}

/* ---------- end of a section: key terms, questions, activities ---------- */
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.tb-actions{display:flex;flex-wrap:wrap;gap:8px;margin-top:18px}
.tb-actions .btn{white-space:normal;text-align:left}

/* ---------- end of the chapter ---------- */
.tb-chapter-end{margin-top:12px;padding:30px 30px 28px;border-radius:18px;background:#191a20;color:#fff;font-family:var(--tb-ui)}
.tb-chapter-end .eyebrow{margin:0;color:var(--tb-lime);font-size:14px;letter-spacing:.01em}
.tb-book .tb-chapter-end h2{margin:8px 0 6px;font:600 30px/1.15 var(--tb-head);letter-spacing:-.03em;color:#fff}
.tb-chapter-end>p{margin:0 0 18px;color:#d9dae2;font-size:15px;line-height:1.55}
.tb-chapter-end .btn.ghost{background:transparent;color:#fff;border-color:#ffffff4d}
.tb-chapter-end .btn.hot{background:var(--tb-lime);color:#191a20}
.tb-chapter-nav{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-top:22px}
.tb-chapter-link{display:grid;gap:4px;min-height:64px;padding:13px 16px;border:1px solid #ffffff33;border-radius:12px;background:#ffffff0d;color:#fff;text-align:left;cursor:pointer;font-family:var(--tb-ui)}
.tb-chapter-link span{font-size:13px;color:#c6c7d4}
.tb-chapter-link b{font-size:15.5px;line-height:1.35}
.tb-chapter-link.is-next{text-align:right;grid-column:2}
.tb-chapter-link:hover{background:#ffffff1a}
.tb-answer-key{display:none}

/* ---------- reading options: text size, spacing and page colour (kept on this device) ---------- */
.tb-book.tb-size-l{--tb-fs:20px}
.tb-book.tb-size-xl{--tb-fs:22px;--tb-measure:33em}
.tb-book.tb-space-w{--tb-lh:1.95;--tb-ls:.02em;--tb-ws:.08em}
.tb-book.tb-space-w .tb-page .note-l li{margin-bottom:12px}
.tb-book.tb-paper-cream{--tb-paper:#fbf5e3}
.tb-book.tb-paper-cream .tb-practical,.tb-book.tb-paper-cream .tb-keyterms,.tb-book.tb-paper-cream .tb-q-answer,.tb-book.tb-paper-cream .tb-page .written-practice{background:#fffdf6}
.tb-view{position:relative;flex:none}
.tb-view-btn{display:inline-flex;align-items:center;justify-content:center;min-width:44px;min-height:40px;padding:0 10px;border:1px solid var(--tb-rule);border-radius:10px;background:#fff;color:var(--tb-ink);font:700 15px/1 var(--tb-head);cursor:pointer;list-style:none}
.tb-view-btn::-webkit-details-marker{display:none}
.tb-view[open]>.tb-view-btn{border-color:var(--tb-cobalt);background:var(--tb-cobalt-soft)}
.tb-view-panel{position:absolute;top:calc(100% + 8px);right:0;z-index:20;width:min(300px,calc(100vw - 32px));padding:14px 16px 6px;border:1px solid var(--line,#e3e5ea);border-radius:14px;background:#fff;box-shadow:0 18px 44px #22244a26;color:var(--tb-ink);font-family:var(--tb-ui)}
.tb-view-panel fieldset{margin:0 0 12px;padding:0;border:0}
.tb-view-panel legend{margin:0 0 6px;padding:0;font:650 13px/1.3 var(--tb-ui);color:var(--tb-muted)}
.tb-seg{display:flex;gap:4px;padding:3px;border-radius:10px;background:#f2f1f7}
.tb-seg label{flex:1;min-width:0}
.tb-seg input{position:absolute;opacity:0;pointer-events:none}
.tb-seg span{display:flex;align-items:center;justify-content:center;min-height:38px;padding:6px 8px;border-radius:8px;font:600 13px/1.2 var(--tb-ui);color:var(--tb-text);text-align:center;cursor:pointer}
.tb-seg input:checked+span{background:#fff;color:var(--tb-cobalt-ink);box-shadow:0 1px 3px #22244a2e}
.tb-seg input:focus-visible+span{outline:3px solid var(--tb-cobalt);outline-offset:1px}

/* ---------- read marks in the contents ---------- */
.tb-read-mark{display:none}
.tb-toc li.is-read .tb-read-mark{display:block;grid-column:3;align-self:center;width:11px;height:6px;margin:0;border:solid var(--tb-right);border-width:0 0 2.5px 2.5px;transform:rotate(-45deg) translate(2px,-1px)}
.tb-toc li.is-read .tb-toc-code{color:var(--tb-right)}
.tb-opener-list li.is-read .tb-open-code::after{content:'';display:inline-block;width:11px;height:6px;margin:0 0 3px 7px;border:solid var(--tb-right);border-width:0 0 2px 2px;transform:rotate(-45deg)}

/* ---------- glossary words in the textbook ---------- */
.tb-book .tb-page .cell-term{font-weight:inherit!important;border-bottom:1.5px dotted #7d68b3!important}
.tb-book .tb-page b .cell-term,.tb-book .tb-page strong .cell-term{font-weight:700!important}

/* ---------- narrower screens: the contents panel becomes a drawer ---------- */
@media screen{
  .tb-layout{display:block}
  .tb-toc{position:fixed;top:0;bottom:0;left:0;z-index:80;align-self:auto;width:min(360px,88vw);visibility:hidden;transform:translateX(-104%);transition:transform .24s cubic-bezier(.4,0,.2,1),visibility 0s linear .24s}
  .tb-book.toc-open .tb-toc{visibility:visible;transform:none;transition:transform .24s cubic-bezier(.4,0,.2,1),visibility 0s}
  .tb-toc-inner{height:100%;max-height:none;padding-top:max(18px,env(safe-area-inset-top));padding-bottom:max(16px,env(safe-area-inset-bottom));border-radius:0 18px 18px 0;box-shadow:24px 0 60px #1b1a3a33}
  .tb-toc-close,.tb-toc-open{display:inline-flex}
}
@media(max-width:900px){
  .tb-pair{grid-template-columns:minmax(0,1fr) minmax(190px,40%);gap:22px}
  .tb-opener-band{padding:28px 20px}
  .tb-opener-body{padding:28px 28px 30px}
  .tb-opener-covers{padding:4px 28px 28px}
}
@media(max-width:860px){
  .tb-pair{grid-template-columns:minmax(0,1fr);gap:4px}
  .tb-pair>.tb-figure,.tb-pair>.scope-box>.tb-figure,.tb-pair>.tb-higher>.tb-figure{max-width:480px}
}
@media(max-width:700px){
  .tb-book{--tb-stick:56px;margin-top:0}
  .tb-opener-covers{padding:4px 20px 22px}
  .tb-book .tb-opener{grid-template-columns:1fr;border-radius:18px}
  .tb-opener-band{flex-direction:row;align-items:baseline;gap:12px;padding:16px 20px}
  .tb-opener-band::after{display:none}
  .tb-chapter-no{font-size:34px}
  .tb-opener-body{padding:20px 20px 24px}
  .tb-book .tb-title{font-size:32px}
  .tb-opener-list{grid-template-columns:1fr}
  .tb-open-parts{margin-left:0}
  .tb-opener-actions .btn{flex:1 1 40%}
  .tb-opener-actions .btn.hot{flex-basis:100%}
  .tb-runhead{margin:0 -20px 0;padding:7px 14px;border-width:0 0 1px;border-radius:0}
  .tb-runhead-chapter{display:none}
  .tb-runhead .tb-progress{width:44px}
  .tb-view-panel{right:-6px}
  .tb-page{margin:0 -20px;padding:26px 20px 28px;border-width:0;border-radius:0;box-shadow:none}
  .tb-book{--tb-fs:17px}
  .tb-book.tb-size-l{--tb-fs:19px}
  .tb-book.tb-size-xl{--tb-fs:21px}
  .tb-pair{grid-template-columns:1fr;gap:4px}
  .tb-book .tb-figure{max-width:none}
  .tb-book .tb-point-title{flex-basis:100%;font-size:25px}
  .tb-book .tb-group-title{flex-basis:100%;font-size:29px}
  .tb-keyterms dl,.tb-terms-inline{grid-template-columns:1fr}
  .tb-box,.tb-book .tb-page .math-worked,.tb-book .tb-page .written-practice{margin-left:-6px;margin-right:-6px;padding:18px 16px}
  .tb-q{padding-left:0}
  .tb-q::before{position:static;display:inline-block;margin:0 0 8px}
  .tb-chapter-end{margin:12px -20px 0;padding:26px 20px;border-radius:0}
  .tb-chapter-nav{grid-template-columns:1fr}
  .tb-chapter-link.is-next{grid-column:auto;text-align:left}
}
@media(prefers-reduced-motion:reduce){.tb-toc,.tb-book.toc-open .tb-toc{transition:none}}

/* A continuous reading column, with supporting figures rather than slide cards. */
.tb-book{background:var(--tb-paper);padding:0;--tb-measure:100%}
.tb-book .tb-opener{display:block;border:0;border-radius:0;background:transparent;margin-bottom:28px}
.tb-opener-band{display:flex;flex-direction:row;align-items:baseline;gap:10px;padding:20px 0 0;background:none;color:var(--tb-cobalt)}
.tb-opener-band::after{display:none}
.tb-chapter-label,.tb-chapter-no{font:600 13px/1.4 var(--tb-ui);letter-spacing:.02em;color:var(--tb-cobalt)}
.tb-opener-body{padding:16px 0 24px}
.tb-opener-covers{padding:0 0 22px}
.tb-book .tb-title{margin:10px 0 12px}
.tb-trust{font:400 13px/1.6 var(--tb-ui);color:var(--tb-muted);margin:0 0 18px}
.tb-opener-stats span{padding:0 12px 0 0;border-radius:0;background:none;color:var(--tb-muted);font-weight:400}
.tb-opener-list{grid-template-columns:1fr}
.tb-open-parts{display:none}
.tb-book .tb-group-title{font-size:23px}
.tb-book .tb-page .tb-group{padding-bottom:14px;margin-bottom:28px;border-bottom:1px solid var(--tb-rule)}
.tb-book .tb-group .tb-code{color:var(--tb-muted);background:none;padding:0;font-size:14px;transform:none}
.tb-head-row{display:block}
.tb-book .tb-code{padding:0;background:none;color:var(--tb-cobalt);font-size:14px;transform:none;margin:0 0 8px}
.tb-book .tb-point-title{font-size:32px;line-height:1.2}
.tb-point-head{margin-bottom:24px}
.tb-point{padding-bottom:36px;margin-bottom:40px}
.tb-unit{margin-bottom:20px}
.tb-unit:empty{margin:0}
.tb-book .tb-page .note-h{margin:26px 0 10px;font-size:22px}
.tb-book .tb-page .note-l{line-height:var(--tb-lh)}
.tb-book .tb-page .note-l li{padding-left:3px;margin-bottom:7px}
.tb-book .tb-page .note-l .note-l{margin-top:9px;margin-bottom:3px}
.tb-pair{display:block}
.tb-book .tb-text{max-width:none}
.tb-book .tb-figure{position:relative;display:block;width:100%;max-width:640px;margin:24px auto 30px;padding:0}
.tb-book .tb-figure>svg{display:block;width:100%;height:auto;max-height:min(420px,50vh);margin:0 auto;object-fit:contain}
.tb-caption{border:0;margin:10px 0 0;padding:0;text-align:center;font:italic 400 14px/1.5 var(--tb-read);color:var(--tb-muted)}
.tb-fig-no{font-weight:600;color:var(--tb-muted)}
.tb-fig-title{color:inherit}
.tb-book .tb-figure .sw-diagram-open{position:absolute;right:6px;top:6px;display:grid;place-items:center;width:40px;height:40px;min-height:40px;padding:0;margin:0;font-size:0;border:1px solid #d5d2e4;border-radius:10px;background:#ffffffed;color:var(--tb-cobalt)}
.tb-book .tb-figure .sw-diagram-open::before{content:'⛶';font:24px/1 var(--tb-ui)}
.tb-more-figures{margin:26px 0;border-top:1px solid var(--tb-rule);border-bottom:1px solid var(--tb-rule);padding:0}
.tb-more-figures>summary{min-height:48px;padding:13px 0;font:600 14px/1.5 var(--tb-ui);color:var(--tb-cobalt);cursor:pointer}
.tb-more-figures>summary span{margin-left:6px;font-weight:400;color:var(--tb-muted)}
.tb-gallery-intro{font:400 15px/1.6 var(--tb-ui);color:var(--tb-muted)}
.tb-keyterms{border:1px solid var(--tb-rule);border-left:3px solid var(--tb-cobalt);border-radius:10px}
.tb-keyterms dl{grid-template-columns:1fr}
.tb-box{border-radius:10px}
.tb-runhead{margin:0 0 14px}
@media(max-width:700px){
 .tb-book{width:calc(100vw - 32px);max-width:none;margin-left:calc((100% - (100vw - 32px))/2);margin-right:0}
 .tb-page{margin:0;padding:24px 0}
 .tb-runhead{margin:0;padding:6px 0}
 .tb-book .tb-point-title{font-size:28px}
 .tb-book .tb-page .note-h{font-size:21px}
 .tb-book .tb-figure .sw-diagram-open{width:44px;height:44px;min-height:44px}
 .tb-book .tb-figure{max-width:100%}
 .tb-box,.tb-book .tb-page .math-worked,.tb-book .tb-page .written-practice{margin-left:0;margin-right:0}
 .tb-chapter-end{margin-left:0;margin-right:0;border-radius:12px}
}

/* ---------- print or save as PDF ---------- */
@media print{
  @page{margin:15mm 14mm 16mm}
  html:has(.tb-book),body:has(.tb-book){background:#fff!important}
  body:has(.tb-book) :is(.sidebar,.app-topbar,.skip-link,.topic-mode-switcher,.learning-progress-tools,.listen-ui,.listen-bar,#listen-dock,.teacher-banner,.teaching-banner,.toast){display:none!important}
  .tb-book :is(.tb-toc,.tb-toc-backdrop,.tb-runhead,.tb-opener-actions,.tb-opener-hint,.tb-opener-place,.tb-actions,.tb-q-tools,.tb-q-answer,.sw-diagram-open,.tb-chapter-nav,.tb-end-actions,.scope-details,.cell-lab){display:none!important}
  body:has(.tb-book) :is(#root,.workspace-root){width:auto!important;max-width:none!important;margin:0!important;padding:0!important}
  .tb-book{max-width:none;margin:0;color:#111}
  .tb-layout{display:block}
  .tb-book .tb-opener{display:block;border:1.5px solid #222;border-radius:10px;break-after:page}
  .tb-opener-band{display:block;padding:14px 18px;-webkit-print-color-adjust:exact;print-color-adjust:exact}
  .tb-opener-band::after{display:none}
  .tb-chapter-no{font-size:40px}
  .tb-open-parts{display:none}
  .tb-opener-list li{padding:6px 0 7px}
  .tb-opener-stats span{border:1px solid #bbb;background:none}
  .tb-page{padding:0;border:0;border-radius:0;box-shadow:none;background:#fff;font-size:11pt;line-height:1.5}
  .tb-book .tb-page .note-p,.tb-book .tb-page .note-l{font-size:11pt}
  .tb-point{break-inside:auto;padding-bottom:16px;margin-bottom:18px}
  .tb-point-head,.tb-book .tb-page .note-h,.tb-section-title,.tb-group{break-after:avoid}
  .tb-figure,.tb-box,.tb-q,.tb-pair,.math-worked,.written-practice,.eqbox{break-inside:avoid}
  .tb-book .tb-figure>svg{max-height:58mm}
  .tb-pair{display:block}
  .tb-book .tb-figure{max-width:105mm;margin-bottom:10px}
  .tb-unit{margin-bottom:12px}
  .tb-book .tb-page .note-h{margin-top:14px}
  .tb-book .tb-code{-webkit-print-color-adjust:exact;print-color-adjust:exact}
  .tb-opt{min-height:0;padding:4px 8px;border-color:#bbb}
  .tb-opt.is-answer,.tb-opt.is-wrong{background:#fff;border-color:#bbb}
  .tb-book .tb-page .cell-term{border:0!important;color:inherit!important}
  .tb-chapter-end{padding:0;background:none;color:#111}
  .tb-chapter-end .eyebrow,.tb-book .tb-chapter-end h2{color:#111}
  .tb-chapter-end>p{display:none}
  .tb-answer-key{display:block;break-before:page;font-size:10.5pt}
  .tb-answer-key h2{font:600 16pt/1.2 var(--tb-head);margin:0 0 10px}
  .tb-answer-key ol{columns:2;column-gap:28px;padding-left:1.2em}
  .tb-book a{color:inherit;text-decoration:none}
}