/* Catalog and study controls. Content remains readable without JavaScript. */
html.study-navigation{scroll-padding-top:var(--reading-header-offset,150px)}.study-navigation .article-body h2{scroll-margin-top:0}
.header-search{display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:8px 14px;border:1px solid var(--line);border-radius:4px;color:var(--mint);font-size:13px;text-decoration:none}
.library-hero{padding-bottom:8px}.library-start{font-size:14px;color:var(--mint)}.catalog-section{padding-top:0}.catalog-section>h2{font-size:24px;margin:8px 0 14px}.catalog-section .library-toolbar{margin:0;align-items:end}.catalog-section .library-search{max-width:none}.catalog-section .library-toolbar input{min-height:48px}.catalog-section .search-status:empty{display:none}
.catalog-options{display:flex;justify-content:space-between;align-items:center;gap:16px;margin:18px 0}.catalog-options .library-count{margin:0}.catalog-view{display:flex;gap:6px}.catalog-view button,.library-filters button{min-height:44px}.catalog-view button{padding:8px 16px;border:1px solid var(--line);border-radius:4px;background:transparent;color:var(--muted);font-size:12px}.catalog-view button[aria-pressed=true]{background:var(--mint);color:var(--bg);border-color:var(--mint)}
.catalog-routes{border:1px solid var(--line);border-radius:4px;padding:0 18px;margin:16px 0}.catalog-routes>summary{cursor:pointer;min-height:48px;padding:12px 0;font-size:14px;color:var(--ink)}.catalog-routes>summary span{color:var(--mint);font-size:12px;margin-left:10px}.catalog-routes .library-filters{margin:12px 0 24px}.catalog-routes .routes-grid{padding-bottom:20px}.catalog-section .book-order-link{margin:16px 0 22px}
.topic-grid[data-view=list]{grid-template-columns:1fr;gap:0;border-top:1px solid var(--line)}.topic-grid[data-view=list] .topic-card{display:block;min-height:0;border:0;border-bottom:1px solid var(--line);border-radius:0;background:transparent;padding:20px 12px}.topic-grid[data-view=list] .topic-card:hover{background:var(--panel)}.topic-grid[data-view=list] .topic-card h3{font-size:17px;margin:7px 0}.topic-grid[data-view=list] .topic-card p{display:none}.topic-grid[data-view=list] .topic-card.has-text-match p{display:block;margin:12px 0}.topic-grid[data-view=list] .topic-foot{display:none}.topic-grid[data-view=list] .chapter-identity{margin:0 0 6px}.topic-card .read-badge{color:var(--mint);white-space:nowrap}.book-list .read-badge{display:inline}
.prerequisites a{min-height:44px;display:inline-flex;align-items:center;margin:4px 12px 4px 0;padding:6px 2px;line-height:1.6}.prerequisites{display:flow-root}.reading-sidebar .tools button{min-height:44px}.reading-sidebar .study-note{font:11px/1.65 var(--sans);color:var(--muted);margin:0}.home-volume{font:12px/1.7 var(--mono);color:var(--mint);margin:24px 0 0}
.resume-reading{display:flex;justify-content:space-between;gap:24px;padding:22px 24px;margin:20px 0 28px;border:1px solid var(--line);border-radius:5px;background:var(--panel);color:var(--ink)}.resume-reading .eyebrow{margin:0 0 8px}.resume-link{display:inline-block;font-size:17px;line-height:1.5;color:var(--mint);text-decoration:underline;text-underline-offset:4px}.resume-section{font-size:13px;line-height:1.6;margin:6px 0;color:var(--muted)}.resume-reading .study-note{font-size:11px;line-height:1.65;color:var(--muted);margin:8px 0 0}.resume-actions{display:flex;flex-direction:column;justify-content:center;align-items:flex-start;gap:12px;min-width:150px}.read-total{font-size:12px;color:var(--muted)}.resume-actions button{font-size:11px;min-height:44px}.hero-copy .resume-reading{flex-direction:column;padding:18px;gap:12px}.hero-copy .resume-actions{flex-direction:row;align-items:center;justify-content:space-between}.chapter-resume a{max-width:100%;text-align:left;justify-content:flex-start;color:var(--mint)}
.study-dialog-open{overflow:hidden}.study-dialog{width:min(720px,calc(100% - 32px));max-height:85vh;max-height:85dvh;padding:24px;border:1px solid #526c75;border-radius:8px;background:var(--bg);color:var(--ink);font:16px/1.6 var(--sans);overscroll-behavior:contain}.study-dialog::backdrop{background:#000b}.study-dialog-head{display:flex;align-items:center;justify-content:space-between;gap:16px;position:sticky;top:-24px;z-index:1;margin:-24px -24px 20px;padding:20px 24px;background:var(--bg);border-bottom:1px solid var(--line)}.study-dialog-head h2{font-size:20px;font-weight:550;margin:0;line-height:1.3}.study-dialog-head button{min-height:44px;flex-shrink:0}.study-search-label{display:block;color:var(--muted);font-size:13px;margin-bottom:6px}.study-dialog input{display:block;width:100%;min-height:48px;padding:12px 14px;border:1px solid #647f8a;border-radius:4px;background:var(--panel);color:var(--ink);font:inherit}.study-dialog [role=status]{font-size:13px;color:var(--muted)}.study-dialog a{color:var(--mint)}.study-search-result{display:block;border-top:1px solid var(--line);padding:16px 4px;text-decoration:none}.study-search-result small{display:block;color:var(--muted);font-size:11px}.study-search-result strong{display:block;font-size:16px;font-weight:500;line-height:1.5;margin:3px 0 6px}.study-search-result>span{display:block;color:var(--muted);font-size:13px;line-height:1.65}.study-dialog mark{background:#8ce2d12b;color:var(--mint)}.reader-index-content nav{display:grid;gap:2px}.reader-index-content nav a{display:block;min-height:44px;padding:10px 8px;font-size:14px;text-decoration:none;border-bottom:1px solid var(--line);overflow-wrap:anywhere}.reader-index-content a[aria-current]{background:var(--panel)}.reader-toolbar{display:none}.study-announcement{position:fixed;clip-path:inset(50%);width:1px;height:1px;overflow:hidden}
@media(max-width:800px){.reading-header{display:flex;flex-wrap:wrap;gap:0 16px}.reading-header .reading-brand{margin-right:auto}.reading-header .reading-nav{order:3;flex-basis:100%;justify-content:space-between;gap:6px}.header-search{padding:6px 12px}.catalog-section .library-toolbar{display:flex;align-items:end;gap:12px}.catalog-section .library-search{flex-basis:100%}.catalog-section .library-order{flex-basis:100%}.catalog-options{margin:14px 0}.catalog-routes{padding:0 13px}.catalog-routes>summary span{display:block;margin-left:0}.resume-reading{flex-direction:column;gap:16px;padding:18px}.resume-actions{flex-direction:row;align-items:center;justify-content:space-between}.reader-toolbar{position:fixed;bottom:0;left:0;right:0;z-index:16;display:grid;grid-template-columns:1fr 1fr 1.2fr;gap:8px;padding:8px 12px calc(8px + env(safe-area-inset-bottom));background:var(--bg);border-top:1px solid var(--line)}.reader-toolbar button,.reader-toolbar a{display:flex;align-items:center;justify-content:center;min-height:44px;border:1px solid var(--line);border-radius:4px;background:var(--panel);color:var(--ink);font:12px var(--sans);text-decoration:none}.reader-toolbar [aria-pressed=true]{color:var(--bg);background:var(--mint)}.has-reader-toolbar{padding-bottom:calc(72px + env(safe-area-inset-bottom))}.study-dialog{padding:18px}.study-dialog-head{top:-18px;margin:-18px -18px 18px;padding:16px 18px}.study-dialog-head h2{font-size:18px}}
@media print{.header-search,.reader-toolbar,.resume-reading,.chapter-resume,.catalog-view,.catalog-routes,.study-dialog,.study-announcement,[data-mark-read],.study-note{display:none!important}.has-reader-toolbar{padding-bottom:0}}

.study-save-warning{position:fixed;bottom:16px;left:16px;right:16px;z-index:17;margin:0;padding:12px 16px;background:#342b14;color:#fff0c2;border:1px solid #9d8550;border-radius:4px;font:13px/1.5 var(--sans)}
@media(max-width:800px){.study-save-warning{bottom:calc(76px + env(safe-area-inset-bottom))}}
@media print{.study-save-warning{display:none!important}}

.reading-state{display:grid;gap:8px;margin:12px 0 20px}.reading-state button{min-height:44px}


/* Curriculum navigation: all labels and links remain present without JavaScript. */
.catalog-scope{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin:18px 0}.catalog-scope label{display:flex;flex-direction:column;gap:7px;font-size:13px;color:var(--muted)}.catalog-scope select{width:100%;min-width:0;min-height:46px;padding:10px 12px;border:1px solid var(--line);border-radius:4px;background:var(--panel);color:var(--ink);font:inherit}.book-area-index{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px;margin:24px 0 40px}.book-area-index a{padding:14px 16px;border:1px solid var(--line);border-radius:5px;text-decoration:none}.book-area-index span{display:block;font-size:12px;color:var(--muted);margin-top:4px}.book-area{margin:40px 0;scroll-margin-top:var(--reading-header-offset,120px)}.book-area h2{margin-bottom:20px}.book-module{border:1px solid var(--line);border-radius:5px;margin:12px 0;scroll-margin-top:var(--reading-header-offset,120px)}.book-module>summary{padding:16px 20px;cursor:pointer;line-height:1.5}.book-module>summary span{font-size:12px;color:var(--muted);margin-right:12px}.book-module>summary strong{font-weight:500}.book-module[open]>summary{border-bottom:1px solid var(--line)}.book-module .book-list{margin:0;padding:0 20px}.chapter-experiments{display:flex;flex-wrap:wrap;gap:12px;align-items:center;padding:16px 20px;border:1px solid var(--line);border-radius:5px;margin:0 0 28px}.chapter-experiments>span{font-size:13px;color:var(--muted);margin-right:8px}@media(max-width:640px){.catalog-scope,.book-area-index{grid-template-columns:1fr}.book-module>summary span{display:block}.book-module>summary{padding:14px}.book-module .book-list{padding:0 14px}}