/* Spacing, radii and shadows use the locally vendored Open Props tokens. */
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@media(max-width:1060px){#site-nav{gap:15px}.book-map li{grid-template-columns:1fr 120px}.reader-grid{grid-template-columns:260px minmax(0,1fr)}.study-stats>div{padding:19px}.route-grid article{padding:20px}.page-intro{align-items:flex-start}.page-shortcuts{max-width:230px}}
@media(max-width:960px){.menu-toggle{display:block}#site-nav{display:none;position:absolute;top:78px;left:5vw;right:5vw;padding:16px 24px;background:#162021;border:1px solid #ffffff24;border-radius:8px;box-shadow:var(--shadow-4);flex-direction:column;align-items:stretch;gap:3px}#site-nav.is-open{display:flex}#site-nav>a{padding:13px 0}#site-nav .search-nav{padding:11px 14px}.nav-more[open]>div{position:static;background:#101a1b;box-shadow:none;margin:5px 0}.reader-grid{grid-template-columns:1fr}.chapter-list{max-height:230px}.study-stats{grid-template-columns:1fr 1fr}.route-grid{grid-template-columns:1fr}.route-grid p{min-height:0}.route-grid ol{display:grid;grid-template-columns:1fr 1fr;gap:5px 20px}.reading-page .page-intro{flex-direction:column;gap:10px}.page-shortcuts{justify-content:flex-start;max-width:none}.reader-position{flex-wrap:wrap}}
@media(max-width:600px){.math-filter-row{gap:10px;grid-template-columns:1fr}.math-filter-row label{display:flex;align-items:center;justify-content:space-between;gap:12px}.math-filter-row select{width:75%;margin-top:0}.study-ribbon{padding:15px;flex-direction:column;align-items:flex-start;gap:8px;font-size:12px}.topic-actions{align-items:stretch}.topic-actions>div{gap:8px}.topic-actions .permalink{padding:8px}.learning-label{justify-content:space-between}.learning-label select{flex:1;max-width:180px}.source-links{justify-content:flex-start;margin:8px 0 0}.topic-sources li{margin-top:15px}.topic summary strong{font-size:16px}.topic summary small{font-size:12px}.related-topics{display:grid;grid-template-columns:1fr}.book-map li{grid-template-columns:1fr}.study-stats{gap:10px}.study-stats>div{padding:18px}.study-stats strong{font-size:32px}.study-stats small{font-size:10px}.reading-routes,.study-records,.practice-section{padding-top:34px}.backup-actions{flex-wrap:wrap}.study-record{align-items:flex-start;flex-direction:column;gap:15px}.record-controls{gap:14px}.record-controls label{width:calc(50% - 7px)}.record-controls select{min-width:0;width:100%}#record-count{margin-left:0}.practice-card{padding:19px}.practice-card h3{font-size:18px}#quiz-options{grid-template-columns:1fr}.quiz-topline{gap:10px}.quiz-option{font-size:13px;padding:12px}.reader-tools{gap:12px}.reader-tools form{flex-wrap:wrap}.reader-position button{font-size:11px;padding:9px}#pdf-frame{min-height:480px;height:70vh}.credits-grid{grid-template-columns:1fr}.route-grid ol{grid-template-columns:1fr}.reader-main .page-intro h1{font-size:30px}}
@media print{.site-header,.site-footer,.back-top,.topic-actions,.knowledge-tools,.book-map,.study-ribbon{display:none!important}body,:root{background:white!important;color:#111!important}.topic,.topic[open],.topic-body,.topic-example,.topic-sources{background:white!important;color:#111!important;border-color:#aaa!important}.topic-body dd,.topic-body p,.topic-body dt,.topic-sources li{color:#222!important}.reading-page main{max-width:none;margin:0;padding:0}.formula{overflow:visible!important}.topic{break-inside:avoid}}
.entry-grid-four{grid-template-columns:repeat(4,minmax(0,1fr))}.entry-grid-four .entry-art{height:145px}.entry-grid-four .entry-copy{padding:21px}.entry-grid-four .entry-card h3{font-size:19px}.home-wander,.latest-notes{border-top:1px solid var(--line)}.home-feature-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}.home-feature{min-height:240px;padding:30px;display:grid;grid-template-columns:44px 1fr;gap:18px;position:relative;overflow:hidden;border:1px solid var(--line);border-radius:var(--card-round);background:linear-gradient(135deg,#142021,#0f1618);transition:transform .2s ease,border-color .2s}.home-feature::after{content:'';position:absolute;width:230px;height:230px;border-radius:50%;right:-90px;bottom:-125px;background:#becba809;border:1px solid #becba812}.home-feature:hover{transform:translateY(-3px);border-color:#becba84d;color:inherit}.home-feature>span{width:44px;height:44px;display:grid;place-items:center;border:1px solid #ffffff20;border-radius:50%;color:var(--accent)}.home-feature h3{font:400 26px/1.5 'Songti SC',Georgia,serif;margin:12px 0}.home-feature p{font-size:13px;line-height:1.9;color:var(--muted);margin:0}.home-feature div>p:first-child{font-size:10px;letter-spacing:.1em;color:var(--accent)}.home-feature em{position:absolute;left:92px;bottom:28px;font-size:12px;font-style:normal;color:var(--green)}.home-feature-play{background:radial-gradient(circle at 78% 24%,#b9635738 0 8%,transparent 9%),linear-gradient(135deg,#182325,#0e1518)}.latest-notes>.section-heading>a{font-size:12px;color:var(--green)}.latest-notes>div:last-child{border-top:1px solid var(--line)}.latest-notes>div:last-child>a{display:grid;grid-template-columns:45px minmax(0,1fr) auto;gap:18px;align-items:center;padding:21px 5px;border-bottom:1px solid var(--line)}.latest-notes>div:last-child>a:hover{background:#ffffff02;color:inherit}.latest-notes>div:last-child>a>span{font-size:10px;color:var(--accent)}.latest-notes h3{font-size:17px;font-weight:450;margin:0 0 6px}.latest-notes p{font-size:12px;line-height:1.8;color:var(--muted);margin:0}.latest-notes em{font-size:11px;color:var(--muted);font-style:normal;white-space:nowrap}
@media(max-width:1180px){.entry-grid-four{grid-template-columns:1fr 1fr}.entry-grid-four .entry-art{height:175px}}
@media(max-width:760px){.entry-grid-four{grid-template-columns:1fr}.home-feature-grid{grid-template-columns:1fr}.home-feature{min-height:220px;padding:24px;grid-template-columns:38px 1fr}.home-feature>span{width:38px;height:38px}.home-feature h3{font-size:22px}.home-feature em{left:80px;bottom:23px}.latest-notes>div:last-child>a{grid-template-columns:30px minmax(0,1fr)}.latest-notes em{grid-column:2;white-space:normal}.latest-notes p{display:none}}