/* Reading layout; shared typography and page colors come from style.css. */
@import url('/assets/fonts/writing/initials.css');
:root[data-page="writing"]{--sidebar-width:248px;scroll-padding-top:0}
.writing-site .skip-link{z-index:90}
/* Local navigation palettes keep each sidebar distinct from the reading area. */
:root[data-theme="rust"] .book-sidebar{color-scheme:dark;--surface:#756452;--ink:#fff7eb;--muted:#f3e8d8;--line:#a18b71;--focus:#fffaf3;--sidebar-current-ink:#ffe29a;--sidebar-current-bg:#5b4937;scrollbar-color:#bca589 var(--surface)}
:root[data-theme="light"] .book-sidebar{color-scheme:light;--surface:#edf0f2;--ink:#374550;--muted:#586873;--line:#cbd3d9;--focus:#1456a0;--sidebar-current-ink:#1456a0;--sidebar-current-bg:#d3e3f5;scrollbar-color:#b3bfc8 var(--surface)}
:root[data-theme="coal"] .book-sidebar{--sidebar-current-ink:#72c8ff;--sidebar-current-bg:#18364a}
:root[data-theme="navy"] .book-sidebar{--sidebar-current-ink:#92bfff;--sidebar-current-bg:#273855}
:root[data-theme="ayu"] .book-sidebar{--sidebar-current-ink:#ffb454;--sidebar-current-bg:#3c3020}
:root[data-theme="supernova"] .book-sidebar{--sidebar-current-ink:#8cd9ff;--sidebar-current-bg:#17313f}
:root[data-theme="novasuper"] .book-sidebar{--sidebar-current-ink:#732600;--sidebar-current-bg:#e8cec0}
@media(prefers-color-scheme:light){:root:not([data-theme]) .book-sidebar{color-scheme:light;--surface:#edf0f2;--ink:#374550;--muted:#586873;--line:#cbd3d9;--focus:#1456a0;--sidebar-current-ink:#1456a0;--sidebar-current-bg:#d3e3f5;scrollbar-color:#b3bfc8 var(--surface)}}
.book-sidebar{position:fixed;inset:0 auto 0 0;width:var(--sidebar-width);padding:30px 24px 22px;background:var(--surface);color:var(--ink);border-right:1px solid var(--line);display:flex;flex-direction:column;overflow-y:auto;z-index:40;font-size:.85rem;scrollbar-width:thin}
.book-sidebar .book-author{color:var(--muted);font-size:.85rem}
.book-name{font-family:var(--font-heading);font-size:1.4rem;font-weight:600;margin:5px 0 30px}
.sidebar-label{color:var(--muted);font-size:.75rem;margin-bottom:12px}
.book-chapters,.section-links{list-style:none;margin:0;padding:0}
.book-chapters>li+li{margin-top:16px}
.book-sidebar a{display:block}
.book-sidebar a:hover,.book-sidebar a[aria-current="page"]{color:var(--focus)}
.chapter-number{color:var(--muted);font-variant-numeric:tabular-nums}
.sidebar-empty{color:var(--muted);margin-top:10px}
.sidebar-preview{border-top:1px solid var(--line);margin-top:28px;padding-top:20px}
.sidebar-preview>a>span{font-size:.65rem;color:var(--muted);display:inline-block;margin-left:8px;border:1px solid var(--line);padding:1px 4px;border-radius:2px}
.section-links{margin-top:16px;border-left:1px solid var(--line);padding-left:12px;font-size:.8rem;line-height:1.5}
.section-links li{margin:12px 0}
.section-links .subsection-link{padding-left:10px;color:var(--muted);font-size:.75rem}
.book-sidebar .section-links a{margin:-5px -8px;padding:5px 8px;border-radius:4px}
/* Color, weight, background, and a marker make the current subsection obvious. */
.book-sidebar .section-links a[aria-current="location"]{color:var(--sidebar-current-ink,var(--focus));background:var(--sidebar-current-bg,var(--hover));font-weight:600;box-shadow:inset 3px 0 0 currentColor}
.sidebar-bottom{margin-top:auto;padding-top:40px;display:flex;gap:20px;color:var(--muted);font-size:.75rem;align-items:center}
.sidebar-bottom [data-reading-label]{margin-left:auto;font-variant-numeric:tabular-nums}
.book-page{--reader-space:calc(100vw - var(--sidebar-width));margin-left:var(--sidebar-width);min-height:100vh}
.reader-controls{width:max-content;height:58px;display:flex;align-items:center;gap:8px;padding:0 24px;position:sticky;top:0;z-index:50}
.reader-controls .theme-menu{left:0;right:auto}
.reader-button{width:32px;height:32px;display:inline-flex;align-items:center;justify-content:center;border:0;background:var(--surface);color:var(--muted);border-radius:50%;cursor:pointer;padding:7px}
.reader-button[hidden]{display:none}
.reader-button svg{width:18px;height:18px}
.reader-button:hover{background:var(--hover);color:var(--ink)}
.book-main{max-width:calc(var(--content-width) + 48px);padding:40px 24px 25px;margin:0 auto;outline:none;overflow-wrap:break-word}
.book-kicker{font-size:.8rem;color:var(--muted);margin-bottom:12px}
.essay-header{margin-bottom:32px}
.essay-meta{font-size:.8rem;color:var(--muted);display:flex;flex-wrap:wrap;gap:8px}
.inline-contents{font-size:.9rem;border-block:1px solid var(--line);padding:16px 0;margin-bottom:40px}
.inline-contents summary{cursor:pointer;font-weight:500}
.inline-contents ol{list-style:none;padding:0;margin:12px 0 0;display:grid;grid-template-columns:1fr 1fr;gap:10px 24px;font-size:.85rem}
.inline-contents a:hover{text-decoration:underline;text-underline-offset:3px}
.reading-prose h2,.reading-prose h3,.margin-note{scroll-margin-top:82px}
.reading-prose section:first-child{margin-top:0}
/* Preserve the article's decorative initial alongside Ubuntu Sans body text. */
.reading-prose .drop-cap{display:flow-root}
.reading-prose .drop-cap::first-letter{font-family:'Goudy Initialen','New Computer Modern',serif;font-weight:400;font-style:normal;float:left;font-size:100.64px;line-height:.8;letter-spacing:.32px;margin:.0547em .04em 0 0;color:var(--ink)}
.reading-prose .heading-link{text-decoration:none;color:var(--ink)}
.reading-prose .heading-link:hover{color:var(--focus)}
.chapter-deck{color:var(--muted)}
.reading-prose sup{font-size:.7rem;line-height:0;margin-left:2px}
.reading-prose .hash-value{word-break:break-all}
.book-ornament{border-top:1px solid var(--line);margin:40px auto;width:100%;height:0;overflow:hidden;color:transparent}
.reading-prose blockquote{margin:24px 0;padding:8px 0 8px 20px;border-left:2px solid var(--line);color:var(--muted)}
.reading-prose blockquote p{margin:0}
.concept-box{margin:24px 0;background:var(--note-bg);border-left:2px solid var(--note-border);padding:18px 20px}
.concept-box h3{margin:0 0 12px}
.concept-box p{margin:0}
.equation{display:flex;align-items:center;justify-content:center;gap:16px;padding:22px 10px;margin:22px 0;overflow-x:auto;white-space:nowrap}
.equation math{font-size:1.18em;margin-inline:auto;flex-shrink:0}
.fraction{display:inline-flex;vertical-align:middle;flex-direction:column;text-align:center;margin:0 5px}
.fraction>span:first-child{border-bottom:1px solid currentColor;padding:0 5px 2px}
.fraction>span+span{padding-top:2px}
.equation-number{font-size:.8rem;color:var(--muted);margin-left:auto}
.equation>span:first-child{margin-left:auto}
.notebook{margin:24px 0;border:1px solid var(--line);border-radius:5px;overflow:hidden}
.notebook figcaption{display:flex;align-items:center;justify-content:space-between;gap:16px;border-bottom:1px solid var(--line);padding:8px 16px;font: .75rem var(--font-mono);color:var(--muted)}
.notebook button{background:transparent;border:1px solid var(--line);padding:4px 8px;border-radius:3px;color:var(--ink);cursor:pointer;font:inherit;flex-shrink:0}
.notebook button:hover{background:var(--hover)}
.notebook pre code,.notebook pre samp{font:inherit;white-space:pre}
.notebook-output pre{background:var(--paper);border-top:1px solid var(--line)}
.cell-prompt{display:none}
.token-comment{color:var(--muted)}.token-keyword,.token-function{color:var(--focus)}
.reading-details{margin:24px 0;border-block:1px solid var(--line);padding:14px 0}
.reading-details summary{cursor:pointer;font-size:.9rem}
.reading-details p{margin:16px 0 3px}
.article-figure{margin:28px 0}
.article-figure>a{display:block}
.article-figure img{width:100%;height:auto;border-radius:3px}
.article-figure iframe,.article-figure video{width:100%;aspect-ratio:16/9;border:0}
.article-figure figcaption,.reading-prose table caption{font-size:.8rem;line-height:1.5;color:var(--muted);margin-top:10px;text-align:left}
.reading-prose table caption{caption-side:bottom;padding-top:10px}
.capture-placeholder{border:1px dashed var(--note-border);padding:22px 24px;background:var(--surface);border-radius:3px}
.capture-label{font-size:.75rem;color:var(--muted)}
.capture-placeholder h3{margin:10px 0 12px}
.capture-placeholder p{font-size:.9rem;margin-bottom:0}
.capture-placeholder figcaption{border-top:1px solid var(--line);padding-top:12px}
.chapter-navigation{display:flex;justify-content:space-between;gap:24px;border-top:1px solid var(--line);padding-top:24px;margin-top:48px;font-size:.9rem}
.chapter-navigation>a{max-width:48%}
.chapter-navigation>a:last-child{text-align:right}
.chapter-navigation small{display:block;color:var(--muted);font-size:.75rem;margin-bottom:5px}
.book-footer{border-top:1px solid var(--line);margin-top:48px;padding-top:16px;display:flex;justify-content:space-between;gap:16px;color:var(--muted);font-size:.75rem}
.book-footer a{text-decoration:underline;text-underline-offset:3px}
.reading-progress{position:fixed;top:0;left:var(--sidebar-width);right:0;height:2px;z-index:80;pointer-events:none}
.reading-progress span{display:block;height:100%;background:var(--focus);width:0}
.reader-status{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap}
.sidebar-shade{display:none}
.contents-hidden .book-sidebar{display:none}.contents-hidden .book-page{--reader-space:calc(100vw - var(--sidebar-width));margin-left:0}.contents-hidden .reading-progress{left:0}
.template-notice{display:flex;flex-wrap:wrap;gap:6px 16px;padding:12px 0;border-block:1px solid var(--line);margin-bottom:32px;font-size:.8rem;color:var(--muted)}
.writing-hub header{margin-bottom:40px}
.writing-hub .writing-heading>span{color:var(--muted);font-size:.8rem}
@media(max-width:800px){.book-sidebar{display:none;width:min(300px,82vw);box-shadow:8px 0 25px #0002}.book-page{--reader-space:calc(100vw - var(--sidebar-width));margin-left:0}.reading-progress{left:0}.contents-open .book-sidebar{display:flex;z-index:70}.contents-open .sidebar-shade{display:block;position:fixed;inset:0;background:#0007;border:0;z-index:60;width:100%;height:100%;cursor:pointer}.book-main{padding:24px 20px}.reader-controls{padding-inline:16px}}
@media(max-width:500px){.inline-contents ol{grid-template-columns:1fr}.book-footer{flex-direction:column;gap:8px}.capture-placeholder{padding:18px}.notebook figcaption{gap:10px}}
/* Reserve equal gutters on both sides; notes never push the article left. */
@media screen and (min-width:1200px){.book-main{width:min(calc(var(--content-width) + 48px),calc(var(--reader-space) - 368px))}}
@media print{.book-sidebar,.reader-controls,.sidebar-shade,.reading-progress,.chapter-navigation,.book-footer,.notebook button{display:none!important}.book-page{margin:0}.book-main{padding:0;max-width:none}.notebook pre,.notebook pre code{white-space:pre-wrap}.concept-box,.article-figure,.notebook{break-inside:avoid}.reading-prose h2,.reading-prose h3{break-after:avoid}}

/* Chapter frontispiece and learning overview, before the contents and argument. */
.article-opening{margin:0 0 40px}
.article-opening .article-figure{margin:0 0 24px}
.reading-prose .learning-overview{margin:24px 0 0;padding:16px 20px;border-left:0;border-block:1px solid var(--note-border);background:var(--note-bg);color:var(--ink)}
.reading-prose .learning-overview p{margin-bottom:16px}
.reading-prose .learning-overview .learning-label{font-size:.85rem;font-weight:600;margin-bottom:12px}
.learning-overview ul{margin:12px 0 18px}
.reading-prose .learning-overview .prerequisites{font-size:.85rem;color:var(--muted);margin-bottom:0}
@media print{.article-opening .article-figure{break-inside:avoid}.learning-overview{break-inside:avoid}}