:root { color-scheme: light; }
* { box-sizing: border-box; }
body.book-body { margin: 0; color: #263234; background: #020202 url('/files/bg_grey.jpg') repeat; font: 18px/1.72 Georgia, 'Times New Roman', serif; }
a { color: #1b5d62; text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { color: #a53d25; }
.book-site-shell { max-width: 950px; min-width: 320px; margin: 15px auto; overflow: hidden; border-radius: 10px; box-shadow: 0 0 5px 2px rgba(0, 0, 0, .5); background: #fff; }
.book-site-header { min-height: 85px; padding: 10px 30px; color: #fff; background: url('/files/bg_title.jpg') no-repeat left top #2b82b7; font-family: 'Titillium Web', Arial, sans-serif; }
.book-site-header a { color: #fff; text-decoration: none; }
.book-site-name { display: block; font-size: 24px; font-weight: 400; }
.book-site-header span { display: block; margin-top: 1px; color: rgba(255, 255, 255, .72); font: 15px Verdana, Arial, sans-serif; }
.book-site-menu { padding: 0 20px; background: #7299bb; font: 17px 'Titillium Web', Arial, sans-serif; }
.book-site-menu a { display: inline-block; margin-right: 10px; padding: 5px 10px 5px 0; color: #fff; text-decoration: none; }
.book-site-menu a:hover, .book-site-menu .is-current { color: #ffd366; }
.book-page { width: 100%; margin: 0 auto; padding: 42px 28px 70px; background: #f3f0ea; }
.book-page > h1 { margin: 0 0 28px; font-size: clamp(32px, 5vw, 46px); line-height: 1.12; }
.book-card { display: flex; gap: 28px; max-width: 760px; padding: 26px; background: #fffdf9; box-shadow: 0 8px 28px rgba(30, 38, 35, .12); }
.book-card img { width: 145px; height: auto; align-self: flex-start; box-shadow: 4px 5px 14px rgba(0, 0, 0, .2); }
.book-card h2 { margin: 0 0 10px; font-size: 29px; line-height: 1.15; }
.book-card p { margin: 8px 0; }
.book-eyebrow { color: #7a5140; font: 700 13px/1.4 Arial, sans-serif; letter-spacing: .08em; text-transform: uppercase; }
.book-page .book-button { display: inline-block; margin-top: 14px; padding: 10px 16px; border-radius: 4px; color: #fff !important; background: #15555b; font: 700 15px/1.2 Arial, sans-serif; letter-spacing: .01em; text-decoration: none; }
.book-page .book-button:hover, .book-page .book-button:focus-visible { color: #fff !important; background: #0f4449; }
.book-crumbs { margin: 0 0 25px; color: #66706e; font: 14px Arial, sans-serif; }
.book-crumbs span { padding: 0 4px; }
.book-layout { display: grid; grid-template-columns: 255px minmax(0, 1fr); gap: 52px; align-items: start; }
.book-toc { position: sticky; top: 20px; max-height: calc(100vh - 40px); overflow-y: auto; overscroll-behavior: contain; padding: 18px 18px 16px; background: #e6ebe7; font: 14px/1.4 Arial, sans-serif; }
.book-toc-title { display: block; margin-bottom: 12px; color: #263234; font-weight: 700; text-decoration: none; }
.book-edit-link { display: inline-block; margin: -4px 0 13px; color: #1b5d62; font-size: 12px; font-weight: 700; text-decoration: none; }
.book-toc-details > summary { display: none; }
.book-toc-details > ul { margin: 0; padding: 0; list-style: none; }
.book-toc ul { margin: 0; padding: 0; list-style: none; }
.book-toc li { margin: 0 0 8px; padding-left: 2px; }
.book-toc .book-toc-level-1 { margin: 18px 0 8px; color: #263234; font-size: 12px; font-weight: 700; letter-spacing: .04em; text-transform: uppercase; }
.book-toc .book-toc-level-2 { margin: 12px 0 7px 10px; color: #4d5c5b; font-weight: 700; }
.book-toc .book-toc-level-3 { margin-left: 18px; }
.book-toc .book-toc-level-0 { margin-bottom: 14px; font-weight: 700; }
.book-toc .book-toc-item.is-current-section { position: relative; color: #a53d25; }
.book-toc .book-toc-item.is-current-section > a { color: #a53d25; }
.book-toc .is-current-section::before { position: absolute; left: -12px; top: 0; bottom: 0; width: 3px; border-radius: 2px; background: #a53d25; content: ''; }
.book-toc a { color: #405a5b; text-decoration: none; }
.book-toc .is-current { color: #a53d25; font-weight: 700; }
.book-reading { min-width: 0; padding: clamp(24px, 5vw, 56px) clamp(18px, 3.5vw, 40px); background: #fffdf9; box-shadow: 0 8px 28px rgba(30, 38, 35, .1); }
.book-reading h1 { margin: 40px 0 24px; font-size: clamp(30px, 4vw, 44px); line-height: 1.17; }
.book-reading h1:first-child { margin-top: 0; }
.book-reading h2 { margin: 42px 0 20px; font-size: clamp(25px, 3vw, 33px); line-height: 1.22; }
.book-reading h3 { margin: 38px 0 18px; font-size: clamp(23px, 2.7vw, 29px); line-height: 1.26; }
.book-reading h4 { margin: 30px 0 15px; font-size: 21px; line-height: 1.3; }
.book-reading > p { margin: 0 0 18px; text-align: justify; text-indent: 3ch; hyphens: auto; }
.book-reading > p.book-subtext { margin: 24px 0 24px 3.1ch; padding: 13px 18px; background: #f0f4f1; color: #334344; font-size: .92em; line-height: 1.65; text-indent: 2.4ch; }
.book-footnote-ref { margin-left: 2px; font: 700 .72em/1 Arial, sans-serif; vertical-align: super; }
.book-footnote-ref a { text-decoration: none; }
.book-footnotes { margin-top: 44px; padding-top: 18px; border-top: 1px solid #d7d4cb; font: 15px/1.5 Arial, sans-serif; }
.book-footnotes ol { margin: 0; padding-left: 24px; }
.book-footnotes li { margin: 0 0 10px; text-align: justify; hyphens: auto; }
.book-footnotes li > a { font-weight: 700; text-decoration: none; }
.book-reading img { max-width: 100%; height: auto; }
.book-intro { display: flow-root; margin-bottom: 36px; padding-bottom: 28px; border-bottom: 1px solid #d7d4cb; }
.book-intro img { float: left; width: 150px; margin: 0 26px 14px 0; box-shadow: 4px 5px 14px rgba(0, 0, 0, .22); }
.book-intro-description { margin: 10px 0; color: #4e5958; }
.book-figure { margin: 28px auto; text-align: center; }
.book-figure img { max-height: 640px; }
.book-break { width: 30%; margin: 30px auto; border: 0; border-top: 1px solid #b8b5ad; }
.book-chapter-nav { display: flex; justify-content: space-between; gap: 24px; margin-top: 54px; padding-top: 22px; border-top: 1px solid #d7d4cb; font-family: Arial, sans-serif; font-size: 15px; }
.book-chapter-nav a:last-child { margin-left: auto; text-align: right; }
.book-page-nav { position: fixed; right: max(calc((100vw - 950px) / 2 - 60px), 12px); bottom: 18px; z-index: 20; display: flex; flex-direction: column; gap: 10px; }
.book-page-nav-button { position: relative; display: flex; width: 46px; height: 46px; align-items: center; justify-content: center; padding: 0; overflow: visible; border: 0; border-radius: 14px; background: rgba(43, 130, 183, .92); color: #fff; cursor: pointer; box-shadow: 0 8px 22px rgba(0, 0, 0, .18); transition: transform .2s ease, background .2s ease, opacity .2s ease, visibility .2s ease; }
.book-page-nav-button:hover { transform: translateY(-1px); background: rgba(27, 129, 206, .98); }
.book-page-nav-button:focus-visible { outline: 2px solid #ffd366; outline-offset: 2px; }
.book-page-nav-button.is-hidden { visibility: hidden; opacity: 0; pointer-events: none; }
.book-page-nav-icon { display: flex; width: 100%; height: 100%; align-items: center; justify-content: center; }
.book-page-nav-icon svg { display: block; width: 20px; height: 20px; fill: none; stroke: #fff; stroke-width: 2.4; stroke-linecap: round; stroke-linejoin: round; }
.book-page-nav-label { position: absolute; right: 56px; top: 50%; transform: translateY(-50%); padding: 7px 9px; border-radius: 8px; background: rgba(24, 34, 46, .92); color: #fff; font: 13px/1 Arial, sans-serif; opacity: 0; pointer-events: none; transition: opacity .18s ease; }
.book-page-nav-button:hover .book-page-nav-label, .book-page-nav-button:focus-visible .book-page-nav-label { opacity: 1; }
@media (max-width: 780px) { .book-site-shell { margin: 0; border-radius: 0; } .book-site-header { padding: 10px 15px; } .book-site-menu { padding: 0 15px; } .book-site-menu a { margin-right: 6px; font-size: 16px; } .book-page { padding: 27px 10px 46px; } .book-layout { display: block; } .book-toc { position: static; max-height: none; overflow: visible; margin-bottom: 18px; } .book-toc-details > summary { display: block; padding: 10px 12px; border-radius: 5px; background: #d6e0dc; color: #263234; cursor: pointer; font-weight: 700; } .book-toc-details[open] > summary { margin-bottom: 12px; } .book-card { gap: 18px; padding: 18px; } .book-card img { width: 105px; } .book-card h2 { font-size: 23px; } .book-reading { padding: 25px 15px; } .book-chapter-nav { flex-direction: column; } .book-chapter-nav a:last-child { margin-left: 0; text-align: left; } .book-page-nav { right: 8px; bottom: 12px; } .book-page-nav-button { width: 42px; height: 42px; border-radius: 12px; } .book-page-nav-label { display: none; } }