.chapter-identity{font:12px/1.7 var(--mono,monospace);color:#aebfc4;margin-bottom:12px;display:block}.topic-card .chapter-identity{font-size:11px}.card-prerequisites{display:block;color:#aebfc4;font-size:12px;line-height:1.7;margin:18px 0}.book-navigation{display:grid;grid-template-columns:1fr auto 1fr;gap:28px;padding:28px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line);margin:45px 0}.book-navigation a{min-height:44px;line-height:1.6}.book-navigation a:last-child{text-align:right}.book-navigation small{display:block;color:var(--muted);font-size:12px;margin-bottom:6px}.book-navigation>a:nth-child(2){align-self:center;color:var(--mint);font-size:13px}.citation-panel{margin:40px 0 65px;background:var(--panel);border:1px solid var(--line);padding:28px;border-radius:4px}.citation-panel h2{font-size:24px;font-weight:450}.citation-panel p{line-height:1.85;font-size:14px;overflow-wrap:anywhere}.citation-panel a{color:var(--mint)}.copy-status{display:inline-block;margin:10px;font-size:13px}.library-order{display:grid;gap:8px;font-size:12px;color:var(--muted);min-width:165px}.library-order select,.errata-form input,.errata-form textarea,.errata-form select{background:#10232c;border:1px solid #647f8a;color:#e5eeee;border-radius:3px;padding:12px;font:inherit;min-height:44px;max-width:100%;width:100%}.library-toolbar{flex-wrap:wrap}.book-order-link{font-size:13px;color:var(--mint);margin:25px 0}.book-list{list-style:none;padding:0;display:grid;grid-template-columns:1fr 1fr;gap:18px}.book-list li{border:1px solid var(--line);background:var(--panel);border-radius:4px}.book-list a{display:grid;padding:24px;gap:12px;text-decoration:none}.book-list a:hover{background:#153039}.book-list span{color:var(--mint);font-size:12px}.book-list strong{font-size:19px;font-weight:500;line-height:1.45}.book-list small{font-size:14px;color:var(--muted);line-height:1.8}.edition-content{margin:0 0 70px;max-width:1050px}.edition-content section{margin:40px 0}.edition-content h2{font-size:27px;font-weight:450;margin-bottom:20px;line-height:1.4}.edition-content h3{font-size:19px;font-weight:500;line-height:1.6}.edition-content p,.edition-content li{font-size:16px;line-height:1.9;color:var(--muted)}.edition-content a{color:var(--mint)}.edition-content a.primary{color:#081218}.edition-content pre{white-space:pre-wrap;overflow-wrap:anywhere;border:1px solid var(--line);background:var(--panel);padding:24px;line-height:1.9;color:#e5eeee;font-size:15px}.correction{border-top:1px solid var(--line);padding:22px 0}.correction summary{cursor:pointer;padding:12px 0;color:var(--mint);min-height:44px}.correction details p{overflow-wrap:anywhere;font-size:14px}.correction h4{font-size:14px}.errata-form{display:grid;gap:23px;max-width:800px}.errata-form label{display:grid;gap:9px;line-height:1.5;font-size:15px}.errata-form output{font-size:14px;color:var(--mint)}.errata-form p{font-size:14px}.errata-form textarea{resize:vertical}.model-directory{display:grid;grid-template-columns:1fr 1fr;gap:22px;margin-top:30px}.model-directory h2{font-size:24px}.model-directory p{font-size:14px}.model-directory-link{padding-bottom:28px;font-size:13px}.home-model-links{margin-top:25px;font-size:13px;line-height:2.1}.home-model-links a,.home-book-link a,.model-directory-link a{color:var(--mint)}.home-book-link{padding-top:24px}.edition-footer-links{max-width:500px;line-height:2.1!important}.hero h1{font-size:clamp(44px,5.2vw,77px);letter-spacing:-.055em;line-height:1.09}.hero-description{max-width:540px}.header nav{gap:22px}.reading-nav{gap:22px}.reading-nav a{display:inline-flex!important;min-height:44px}.reading-footer p{line-height:2}.topic-card{overflow-wrap:anywhere}.topic-card h3{line-height:1.4}.chapter-identity+ .eyebrow{margin-top:18px}.copy-citation[hidden]{display:none}.reading-nav a:focus-visible,.book-list a:focus-visible,.edition-content a:focus-visible,.errata-form :focus-visible{outline:2px solid var(--mint);outline-offset:5px}.hero-footnote{max-width:480px}#story-canvas{display:block}.reading-meta{max-width:100%;white-space:normal}#motion{min-width:44px;min-height:44px}
@media(max-width:800px){.hero h1{font-size:clamp(41px,9vw,66px)}.reading-nav{gap:8px;flex-wrap:wrap;justify-content:space-between}.reading-nav a{font-size:11px}.reading-header{padding-inline:20px}.header nav{gap:16px}.book-list,.model-directory{grid-template-columns:1fr}.book-navigation{gap:16px;grid-template-columns:1fr 1fr}.book-navigation>a:nth-child(2){grid-column:1/-1;grid-row:2;text-align:center}.book-navigation a:last-child{grid-column:2}.citation-panel{padding:23px 20px}.citation-panel h2{font-size:23px}.edition-content h2{font-size:25px}.edition-content pre{padding:17px;font-size:12px}.library-order{min-width:135px}.model-directory .connection-card{padding:22px}.home-model-links{display:grid;gap:10px;font-size:12px}.book-list a{padding:21px}.header nav a{font-size:11px}.chapter-identity{font-size:11px}}
@media(max-width:360px){.header nav{gap:12px}.header nav a{font-size:10px}.reading-nav a{font-size:10px}.reading-nav{gap:5px}.hero h1{font-size:40px}.reading-header{padding-inline:14px}.book-navigation{font-size:13px}.citation-panel{padding:20px 15px}}
@media print{.book-navigation,.copy-citation,.copy-status,.errata-form .reading-actions{display:none}.citation-panel{background:white;border-color:#aaa;break-inside:avoid}.citation-panel p,.chapter-identity{color:#222}.edition-content p,.edition-content li{color:#222}.edition-content pre{color:#111;background:#fff}.book-list{display:block}.book-list li{break-inside:avoid}}

.story-step{opacity:1}.story-step.active h3{color:var(--mint)}.math-block:focus-visible,.article-body pre:focus-visible{outline:2px solid var(--mint);outline-offset:4px}

.concept-index{display:flex;flex-wrap:wrap;gap:10px;margin:25px 0 45px;scroll-margin-top:110px}.concept-index a{border:1px solid var(--line);border-radius:4px;padding:10px 14px;font-size:14px;min-height:44px}.concept-entry{border-top:1px solid var(--line);padding:28px 0;max-width:800px;scroll-margin-top:110px}.concept-entry:target{border-color:var(--mint)}.concept-entry p{overflow-wrap:anywhere}.concept-entry li{padding:5px 0}.concept-entry h3{margin-top:22px}.correction .katex{color:var(--ink)}.correction details p{overflow-x:auto}.concept-index a:hover{background:var(--panel)}

.area-legend{gap:8px}.area-legend>button{min-height:44px;min-width:44px;padding:8px 10px;font-size:11px}

.citation-panel>summary{cursor:pointer;font-size:16px;min-height:44px;line-height:1.5;padding:10px 0}.citation-panel>summary:focus-visible{outline:2px solid var(--mint);outline-offset:4px}.citation-panel:not([open]){padding-top:10px;padding-bottom:10px}.curriculum-modules>.curriculum-module:first-child{border-top:0}.curriculum-modules>.curriculum-module:last-child{border-bottom:0}

/* Shared search results and keyboard-visible highlights. */
mark{background:#8ce2d13b;color:inherit;border-radius:2px;padding:0 .05em}
.search-status{font-size:13px;color:var(--muted);line-height:1.6}
.search-status:empty{display:none}
.search-dialog .search-status{padding:0 24px 12px;margin:0}
.search-dialog #global-search-retry{margin:0 24px 14px;min-height:44px}
.search-result .search-excerpt{display:block;font-size:12px;line-height:1.7;color:var(--muted);margin-top:7px;overflow-wrap:anywhere}
.search-result>span{min-width:0;overflow-wrap:anywhere}
.search-match{display:block;color:var(--mint);font-size:12px;line-height:1.6;margin:12px 0;overflow-wrap:anywhere}
.search-all{display:block;padding:18px 24px;border-top:1px solid var(--line);color:var(--mint);font-size:13px;line-height:1.6;min-height:44px}
.search-all:focus-visible{outline:2px solid var(--mint);outline-offset:-5px}
#topic-search-retry{margin-bottom:20px}
.resource-index{display:flex;flex-wrap:wrap;gap:.5rem;margin-top:1.6rem}
.resource-index a{display:grid;place-items:center;min-width:3.25rem;min-height:2.75rem;padding:.35rem .65rem;border:1px solid var(--line,#25404a);border-radius:.5rem}
.resource-directory{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:1.2rem;margin:0 0 3rem}
.resource-card{min-width:0;padding:1.4rem;border:1px solid var(--line,#25404a);border-radius:1rem;background:var(--panel,#0e1b24);scroll-margin-top:7rem}
.resource-card h2{font-size:1.22rem;line-height:1.45;margin:.6rem 0}
.resource-card h2 a{text-decoration:none}
.resource-counts,.resource-note{font-size:.92rem;line-height:1.6}
.resource-card details{margin-top:.85rem;border-top:1px solid var(--line,#25404a);padding-top:.85rem}
.resource-card summary{cursor:pointer;min-height:2rem}
.resource-card pre{overflow-x:auto;padding:.85rem;border-radius:.4rem;background:#081218;max-width:100%;font-size:.85rem}
.resource-files{padding-left:1.25rem;font-size:.8rem;line-height:1.7}
.resource-files code{overflow-wrap:anywhere}
.resource-reading{margin:1.1rem 0 0}
.resource-pending{border-style:dashed}
.resource-method{max-width:78ch;margin-bottom:3rem}
@media(max-width:760px){.resource-directory{grid-template-columns:1fr}.resource-card{padding:1.1rem}}
.errata-receipt{padding:20px;border:1px solid var(--line);border-left:3px solid var(--mint);background:var(--panel)}.errata-receipt code{overflow-wrap:anywhere}.errata-form button:disabled{opacity:.65;cursor:default}.errata-trap[hidden]{display:none}.errata-admin{margin-top:35px;font-size:13px}