/* Quizzman Books · macOS-inspired reading space. Shared QMF header stays authoritative. */
:root{--bk-bg:#f7f8fa;--bk-surface:#fff;--bk-side:#f0f2f5;--bk-ink:#232936;--bk-muted:#687283;--bk-line:#e4e7ec;--bk-blue:#316ac5;--bk-soft:#e6edf8;--bk-hero:#eeeee8;--bk-radius:12px;--qm-book-bg:var(--bk-bg);--qm-book-ink:var(--bk-ink);--qm-book-muted:var(--bk-muted);--qm-book-accent:var(--bk-blue);--qm-book-card-border:var(--bk-line);--qm-book-surface:var(--bk-surface)}
html[data-theme=dark]{--bk-bg:#171a20;--bk-surface:#20242c;--bk-side:#1c2027;--bk-ink:#edf0f5;--bk-muted:#a8b1bf;--bk-line:#343a45;--bk-blue:#94bafa;--bk-soft:#2a3a53;--bk-hero:#2a302f;color-scheme:dark}
html{scroll-padding-top:90px}body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;-webkit-font-smoothing:antialiased;background:var(--bk-bg);color:var(--bk-ink)}
*,*:before,*:after{box-sizing:border-box}button,input{font:inherit}button{cursor:pointer}a,button,input{-webkit-tap-highlight-color:transparent}a:focus-visible,button:focus-visible,input:focus-visible{outline:3px solid var(--bk-blue);outline-offset:4px}button:disabled{cursor:default;opacity:.4}[hidden]{display:none!important}.bk-skip{position:fixed;left:16px;top:-80px;z-index:1000;background:var(--bk-surface);padding:12px 20px;border-radius:8px;color:var(--bk-blue)}.bk-skip:focus{top:12px}
.books-main{max-width:none;margin:0;padding:0;width:100%;flex:1}.books-footer{background:var(--bk-bg);border-color:var(--bk-line);padding:28px 24px;font-size:12px;line-height:1.8}.books-footer p{margin:12px 0 0}.books-footer a{color:var(--bk-muted);font-weight:500}.books-footer-links{gap:22px;margin:0}.bk-app{max-width:1600px;margin:0 auto;display:grid;grid-template-columns:214px minmax(0,1fr);min-height:calc(100vh - 60px)}
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.bk-hero{min-height:322px;border-radius:14px;background:var(--bk-hero);display:grid;grid-template-columns:1fr 1fr;align-items:center;padding:36px 37px;overflow:hidden;gap:20px;position:relative}.bk-eyebrow{font-size:9px;letter-spacing:1.8px;font-weight:650;color:var(--bk-muted);display:block;line-height:1.6}.bk-hero .bk-eyebrow{color:#63776c}.bk-hero h1{font-size:clamp(28px,3vw,43px);line-height:1.24;letter-spacing:-1.6px;font-weight:650;margin:15px 0 13px;color:var(--bk-ink)}.bk-hero p{font-size:12px;line-height:1.9;color:var(--bk-muted);margin:0}.bk-hero-actions{display:flex;align-items:center;gap:15px;margin-top:23px}.bk-button{padding:11px 15px;border-radius:7px;background:#294e43;color:#fff;display:inline-flex;align-items:center;gap:19px;font-size:11px;font-weight:550;text-decoration:none;white-space:nowrap}.bk-button:hover{background:#366454}.bk-hero-actions>span{font-size:9px;color:var(--bk-muted);white-space:nowrap}.bk-hero-books{position:relative;display:flex;align-items:center;justify-content:center;padding:0 12px;height:255px}.bk-hero-books>a{position:absolute;display:block;width:145px;text-decoration:none;color:inherit;transform:rotate(-13deg) translate(-95px,4px);z-index:1;transition:transform .25s}.bk-hero-books>a:nth-child(2){transform:translateY(-9px);z-index:3}.bk-hero-books>a:nth-child(3){transform:rotate(13deg) translate(95px,4px);z-index:2}.bk-hero-books>a:hover{z-index:4;translate:0 -7px}.bk-hero-books .bk-cover{box-shadow:5px 13px 18px #1e30252b}.bk-hero-books:after{position:absolute;bottom:1px;left:8%;right:8%;height:6px;background:#1e302519;filter:blur(8px);content:""}
.bk-cover{position:relative;isolation:isolate;display:flex;flex-direction:column;align-items:center;text-align:center;aspect-ratio:2/3;width:100%;border-radius:3px 6px 6px 3px;overflow:hidden;background:linear-gradient(115deg,var(--cover-color),var(--cover-deep));color:#fff3dd;box-shadow:1px 3px 4px #15213612,4px 9px 13px #15213618;padding:15px 13px 11px 18px;transition:translate .22s,box-shadow .22s}.bk-cover:before{content:"";position:absolute;inset:0;pointer-events:none;border-radius:inherit;background:linear-gradient(90deg,#0006 0,transparent 3%,#fff2 4%,#0002 5%,transparent 8%,transparent 97%,#fff2);box-shadow:inset 0 0 0 1px #ffffff12;z-index:3}.bk-cover:after{content:"";position:absolute;inset:7px;border:1px solid color-mix(in srgb,var(--cover-gold) 23%,transparent);border-left:0;pointer-events:none;border-radius:1px}.bk-cover-brand{font-size:6px;font-weight:500;letter-spacing:1.4px;color:var(--cover-gold);margin-bottom:16px;white-space:nowrap;position:relative;z-index:2}.bk-cover-name{font-family:"Source Serif 4",Georgia,serif;font-size:clamp(15px,1.35vw,21px);font-weight:500;line-height:1.3;position:relative;z-index:2;text-wrap:balance;max-height:3.9em;overflow:hidden}.bk-cover-han{font-family:"LXGW WenKai","Kaiti SC",serif;font-size:13px;letter-spacing:3px;color:var(--cover-gold);margin-top:7px;position:relative;z-index:2;max-height:2.8em;overflow:hidden;line-height:1.4}.bk-cover-art{position:absolute;width:100%;height:67%;bottom:14px;left:0;color:var(--cover-gold);opacity:.8;z-index:-1}.bk-cover-author{font-size:8px;color:var(--cover-gold);margin-top:auto;z-index:2;max-width:100%;line-height:1.4}.bk-cover-edition{font-size:5px;letter-spacing:1.4px;opacity:.65;margin-top:7px;z-index:2}.bk-card{display:block;min-width:0;text-decoration:none;color:var(--bk-ink);height:100%}.bk-card:hover .bk-cover{translate:0 -5px;box-shadow:2px 7px 8px #1521360d,5px 15px 20px #15213626}.bk-card-info{display:flex;flex-direction:column;gap:5px;margin-top:16px;padding-left:1px}.bk-card-info strong{font-size:13px;line-height:1.4;font-weight:600;letter-spacing:-.1px}.bk-card-info>span{font-size:11px;color:var(--bk-muted);line-height:1.4}.bk-card-info small{font-size:9px;line-height:1.6;color:var(--bk-muted);margin-top:1px}.bk-card-info small span{margin:0 3px;opacity:.6}
.bk-shelf{margin-top:30px;scroll-margin-top:90px}.bk-section-head{display:flex;align-items:end;justify-content:space-between;gap:16px;margin-bottom:21px}.bk-section-head h2{font-size:21px;font-weight:650;line-height:1.4;letter-spacing:-.5px;margin:0}.bk-section-head .bk-eyebrow{margin-bottom:6px;font-size:8px}.bk-section-head>span,.bk-section-head>a{font-size:10px;color:var(--bk-muted);text-decoration:none;white-space:nowrap;line-height:1.8}.bk-section-head>a{color:var(--bk-blue)}.bk-section-head>a span{margin-left:7px}.bk-grid{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(6,minmax(0,1fr));gap:25px}.bk-grid>li{min-width:0}.bk-reading-note{margin:33px 0;display:flex;align-items:center;gap:17px;border-block:1px solid var(--bk-line);padding:19px 0;color:var(--bk-muted)}.bk-reading-note>i{font-size:20px;color:#728878}.bk-reading-note p{margin:0;flex:1;font-size:11px;line-height:1.85}.bk-reading-note strong{color:var(--bk-ink);font-weight:600}.bk-reading-note>span{font-family:serif;font-size:20px;white-space:nowrap;color:#9a978b;letter-spacing:6px}.bk-catalog-head{margin-bottom:18px}.bk-filters{display:flex;flex-wrap:wrap;gap:5px;padding-bottom:6px}.bk-filters button{background:none;border:1px solid transparent;border-radius:6px;padding:7px 11px;min-height:34px;font-size:11px;white-space:nowrap;color:var(--bk-muted)}.bk-filters button:hover{background:var(--bk-surface)}.bk-filters button[aria-pressed=true]{background:var(--bk-surface);color:var(--bk-ink);border-color:var(--bk-line);box-shadow:0 1px 3px #00000005;font-weight:600}.bk-catalog .bk-shelf{padding-top:20px;margin-top:20px;border-top:1px solid var(--bk-line)}.bk-catalog .bk-section-head h2{font-size:17px}.bk-catalog .bk-grid{row-gap:30px}.bk-endnote{display:flex;justify-content:center;align-items:center;gap:10px;margin-top:50px;padding:30px 0 0;border-top:1px solid var(--bk-line);font-size:10px;line-height:1.6;color:var(--bk-muted)}.bk-empty{text-align:center;padding:55px 20px;color:var(--bk-muted)}.bk-empty>i{font-size:24px}.bk-empty h3{font-size:18px;color:var(--bk-ink)}.bk-empty p{font-size:13px}.bk-empty button{border:1px solid var(--bk-line);background:var(--bk-surface);border-radius:7px;padding:10px 15px;color:var(--bk-blue);font-size:12px}.bk-resume{margin-top:27px}.bk-resume-link{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:18px 21px;border:1px solid var(--bk-line);border-radius:10px;background:var(--bk-surface);text-decoration:none;color:var(--bk-ink);margin-top:8px}.bk-resume-link strong{font-size:14px;display:block;margin-bottom:5px}.bk-resume-link small{font-size:11px;color:var(--bk-muted)}.bk-resume-link>span:last-child{font-size:12px;color:var(--bk-blue)}
/* Book overview */
.page-book-detail .books-main{max-width:1060px;margin:auto;padding:30px 40px 65px}.ebook-hub{max-width:100%;margin:0;padding:0}.book-breadcrumb{font-size:12px;margin-bottom:35px}.book-breadcrumb-list{list-style:none;display:flex;align-items:center;gap:12px;padding:0;margin:0;color:var(--bk-muted)}.book-breadcrumb a{color:var(--bk-muted);text-decoration:none}.book-breadcrumb i{font-size:10px;margin-right:5px}.book-breadcrumb-current{color:var(--bk-ink)}.ebook-hero{grid-template-columns:220px minmax(0,1fr);gap:60px;align-items:center;margin-bottom:48px}.ebook-cover-wrap{width:100%;padding:6px 0}.bk-detail-cover .bk-cover{padding:23px 22px 19px 27px;box-shadow:7px 18px 32px #17212c29}.bk-detail-cover .bk-cover-brand{font-size:8px;letter-spacing:1.8px;margin-bottom:23px}.bk-detail-cover .bk-cover-name{font-size:29px}.bk-detail-cover .bk-cover-han{font-size:19px;letter-spacing:5px}.bk-detail-cover .bk-cover-author{font-size:11px}.bk-detail-cover .bk-cover-edition{font-size:6px;margin-top:13px}.ebook-han-display{font-size:21px;letter-spacing:5px;color:var(--bk-muted)!important;font-weight:400;margin:0 0 10px}.ebook-meta .bk-eyebrow{margin:0 0 9px}.ebook-meta h1{font-family:inherit;font-weight:650;font-size:37px;letter-spacing:-1.2px;line-height:1.2;color:var(--bk-ink)!important;margin:0 0 12px}.ebook-byline{color:var(--bk-muted)!important;font-size:14px}.ebook-description{font-size:14px;line-height:1.85;color:var(--bk-muted)!important;margin-bottom:22px}.ebook-actions{gap:9px;margin-bottom:25px}.ebook-btn-read{background:#3269bc;color:#fff!important;border-radius:7px;font-size:13px;padding:12px 19px;box-shadow:none;letter-spacing:0;gap:13px}.ebook-btn-read:hover{background:#25569f;box-shadow:none;transform:none}.ebook-btn-ghost{border:1px solid var(--bk-line);background:var(--bk-surface)!important;color:var(--bk-ink)!important;border-radius:7px;display:inline-flex;align-items:center;gap:7px;font-size:12px;padding:11px 15px}.ebook-btn-ghost[aria-pressed=true]{background:var(--bk-soft)!important;color:var(--bk-blue)!important}.ebook-facts{gap:0;border-top:1px solid var(--bk-line);padding-top:20px}.ebook-facts li{border:0;background:none!important;padding:0 25px 0 0;gap:6px;min-width:0}.ebook-facts span{font-size:9px;color:var(--bk-muted)!important}.ebook-facts strong{font-size:12px;color:var(--bk-ink)!important;font-weight:500}.ebook-chapters{padding:25px 28px;border:1px solid var(--bk-line);border-radius:12px;background:var(--bk-surface);scroll-margin-top:90px}.ebook-chapters-head{border-color:var(--bk-line);padding-bottom:18px;margin-bottom:10px}.ebook-chapters-head h2{color:var(--bk-ink)!important;font-size:20px;font-weight:600}.ebook-chapters-head span{color:var(--bk-muted)!important;font-size:12px}.ebook-ch-list{grid-template-columns:repeat(3,minmax(0,1fr));gap:5px 24px}.ebook-ch-item a{padding:12px 8px;border-radius:6px;grid-template-columns:25px minmax(0,1fr) auto;gap:9px;min-height:60px}.ebook-ch-item a:hover{background:var(--bk-bg)!important}.ebook-ch-title{font-size:13px;line-height:1.5;color:var(--bk-ink)!important;font-weight:500}.ebook-ch-num{color:var(--bk-muted);font-size:11px}.ebook-ch-han{color:var(--bk-muted)!important;font-size:11px;max-width:100%}.ebook-ch-go{font-size:13px}
/* Reader: document scrolling, matching the SSR DOM and retaining semantic text layers. */
body.page-ebook-reader{--er-bg:#faf9f6;--er-surface:#fff;--er-ink:#292b30;--er-ink-muted:#747780;--er-han-ink:#343a36;--er-accent:#3569b7;--er-border:#e5e4df;--er-font-sans:-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;--er-font-serif:"Source Serif 4","Noto Serif",Georgia,serif;--er-font:var(--er-font-serif);--er-top-h:56px;--er-toc-w:245px;background:var(--er-bg);padding:0;font-family:var(--er-font-sans)}
html[data-er-theme=sepia] body.page-ebook-reader{--er-bg:#f3ead8;--er-surface:#f7efdf;--er-ink:#453b2d;--er-ink-muted:#796b53;--er-han-ink:#493b2c;--er-border:#dcd0b8;--er-accent:#876336}html[data-er-theme=dark] body.page-ebook-reader{--er-bg:#1d2026;--er-surface:#252930;--er-ink:#e0e3e8;--er-ink-muted:#a4aab4;--er-han-ink:#e5e3d9;--er-border:#383e47;--er-accent:#9bbcf2}.page-ebook-reader .books-main{max-width:none;padding:0;margin:0}.page-ebook-reader .books-footer{display:none}.er-shell{min-height:calc(100vh - 60px)}.er-topbar{height:auto;min-height:56px;top:0;flex-wrap:wrap;gap:12px;padding:10px 21px;border-color:var(--er-border);background:color-mix(in srgb,var(--er-surface) 92%,transparent);backdrop-filter:blur(20px);z-index:45;position:sticky}.er-crumbs{flex:1;min-width:100px;display:flex;gap:9px;align-items:center;overflow:hidden;white-space:nowrap;font-size:12px}.er-crumb-book{color:var(--er-ink)!important;font-weight:550}.er-crumb-sep,.er-crumb-chapter{color:var(--er-ink-muted);overflow:hidden;text-overflow:ellipsis}.er-modes{display:flex;gap:2px;background:color-mix(in srgb,var(--er-ink) 6%,transparent);border-radius:7px;padding:3px;max-width:100%;overflow:auto}.er-modes button{background:none;border:0;padding:7px 11px;min-height:30px;color:var(--er-ink-muted);font-size:11px;border-radius:5px;white-space:nowrap}.er-modes button[aria-pressed=true]{background:var(--er-surface);color:var(--er-ink);box-shadow:0 1px 4px #00000012;font-weight:550}.er-tools{display:flex;gap:2px}.er-icon-btn{width:33px;height:33px;font-size:12px;border-radius:6px}.er-progress{position:sticky;top:var(--reader-bar-height,56px);height:2px;z-index:46;background:var(--er-border)}.er-progress-bar{height:100%;width:0;background:var(--er-accent)}.er-layout{display:flex;align-items:flex-start;flex:1;min-width:0}.er-toc{top:calc(var(--reader-bar-height,56px) + 2px);width:var(--er-toc-w);max-height:calc(100dvh - var(--reader-bar-height,56px) - 2px);height:calc(100dvh - var(--reader-bar-height,56px) - 2px);border-color:var(--er-border);background:color-mix(in srgb,var(--er-surface) 40%,var(--er-bg));padding:8px;z-index:43}.er-toc-header{padding:17px 13px 20px;display:flex;flex-direction:column;gap:7px}.er-toc-header strong{font-size:14px;font-weight:600}.er-toc-header span{font-size:10px;color:var(--er-ink-muted)}.er-toc-list{padding:0 0 25px}.er-toc-item>a{padding:10px;font-size:12px;line-height:1.5;gap:5px}.er-toc-item.is-active>a{color:var(--er-accent);background:color-mix(in srgb,var(--er-accent) 11%,transparent);font-weight:550}.er-toc-num{font-size:10px;padding-top:2px}.er-toc-sections{padding:7px 0 7px 35px}.er-toc-sections a{font-size:10px;padding:5px 0;line-height:1.5}.er-reader{min-width:0;flex:1;padding:54px clamp(24px,5vw,85px) 65px}.er-prose{max-width:var(--er-measure,38rem);margin:auto}.er-shell[data-mode=parallel] .er-prose{max-width:78rem}.er-chapter-header{max-width:var(--er-measure,38rem);margin:0 auto 43px;padding:0 0 28px;border-bottom:1px solid var(--er-border);text-align:left}.er-han-title{font-family:var(--er-font-sans);font-size:10px;color:var(--er-ink-muted);letter-spacing:2px;margin:0 0 15px}.er-title{font-family:var(--er-font-serif);font-size:36px;font-weight:500;line-height:1.3;letter-spacing:-.7px;margin:0 0 13px;color:var(--er-ink)}.er-meta{font-size:11px;color:var(--er-ink-muted);line-height:1.7;margin:0}.er-reader .er-body{display:block;font-family:var(--er-font);font-size:var(--er-size,19px);line-height:var(--er-leading,1.85);color:var(--er-ink)}.er-layers{font-family:var(--er-font);font-size:inherit;line-height:inherit}.er-layer{max-width:100%;margin-bottom:32px;overflow-wrap:anywhere}.er-layer-title{font-size:10px;letter-spacing:1px;color:var(--er-ink-muted);font-weight:550;margin-bottom:20px}.er-layer[data-layer=original]{color:var(--er-han-ink);line-height:2;letter-spacing:.07em}.er-shell[data-mode=original] .er-layer[data-layer=original],.er-shell[data-mode=parallel] .er-layer[data-layer=original]{font-size:calc(var(--er-size,19px)*1.3)}.er-layer p{text-align:left!important;line-height:inherit}.er-layer h2:not(.er-layer-title){font-size:.8em;color:var(--er-ink-muted);font-weight:600;margin:1.8em 0 .9em}.er-layer:first-child h2:not(.er-layer-title){margin-top:0}.er-shell[data-mode=parallel] .er-layers{column-gap:42px}.er-reading-status{max-width:var(--er-measure,38rem);margin:35px auto 0;display:flex;justify-content:space-between;gap:12px;color:var(--er-ink-muted);font-size:10px}.er-nav{display:flex;gap:20px;max-width:var(--er-measure,38rem);margin:17px auto 0;padding-top:24px;border-top:1px solid var(--er-border)}.er-nav-link{flex:1;display:flex;flex-direction:column;gap:7px;color:var(--er-ink);text-decoration:none;min-width:0}.er-nav-link.is-next{text-align:right}.er-nav-dir{font-size:10px;color:var(--er-ink-muted)}.er-nav-title{font-size:13px;line-height:1.5}.er-mode-empty{padding:25px;border:1px solid var(--er-border);border-radius:9px;font-family:var(--er-font-sans);font-size:13px;color:var(--er-ink-muted);line-height:1.8}.er-focus-exit{display:none;position:fixed;right:22px;top:18px;z-index:100;border:1px solid var(--er-border);background:var(--er-surface);color:var(--er-ink-muted);font-size:11px;border-radius:7px;padding:10px 13px}.er-focus-exit kbd{font-family:inherit;font-size:9px;margin-left:10px}.er-shell[data-focus=on] .er-focus-exit{display:block}.er-shell[data-focus=on] .er-topbar,.er-shell[data-focus=on] .er-toc,.er-shell[data-focus=on] .er-toc-backdrop{display:none!important}.page-ebook-reader:has(.er-shell[data-focus=on]) #lab-header{display:none}.er-shell[data-focus=on] .er-progress{top:0}.er-shell[data-focus=on] .er-reader{padding-top:85px}.er-shell.er-font-sans{--er-font:var(--er-font-sans)}.er-reader table{display:block;max-width:100%;overflow:auto;font-size:.75em;border-collapse:collapse}.er-reader :is(td,th){padding:8px;border:1px solid var(--er-border)}.er-reader a{color:var(--er-accent)}.er-reader pre{max-width:100%;overflow:auto;font-size:.8em}.er-toc-backdrop{border:0}
@media(min-width:1500px){.bk-content{padding-inline:50px}.bk-cover-brand{font-size:7px}.bk-cover-author{font-size:9px}.bk-cover-name{font-size:23px}.bk-grid{gap:31px}.bk-hero{min-height:350px}.bk-hero-books>a{width:158px}.bk-hero-books>a:first-child{transform:rotate(-13deg) translate(-107px,4px)}.bk-hero-books>a:nth-child(3){transform:rotate(13deg) translate(107px,4px)}}
@media(max-width:1190px){.bk-app{grid-template-columns:190px minmax(0,1fr)}.bk-content{padding-inline:27px}.bk-grid{grid-template-columns:repeat(4,minmax(0,1fr));gap:22px}.bk-featured .bk-grid>li:nth-child(n+5){display:none}.bk-hero{padding:30px;min-height:310px}.bk-hero-books>a{width:124px}.bk-hero-books>a:first-child{transform:rotate(-13deg) translate(-65px,4px)}.bk-hero-books>a:nth-child(3){transform:rotate(13deg) translate(65px,4px)}.bk-cover-name{font-size:19px}.bk-hero-actions{flex-wrap:wrap;gap:12px}.bk-hero h1{font-size:34px}.bk-hero-books .bk-cover-name{font-size:16px}.bk-hero-books .bk-cover-brand{font-size:5px}.er-crumb-chapter,.er-crumb-sep{display:none}.er-modes button{padding-inline:9px}.er-reader{padding-inline:32px}.ebook-ch-list{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:900px){.bk-app{grid-template-columns:minmax(0,1fr)}.bk-sidebar{display:none}.bk-content{padding-inline:28px}.bk-toolbar{height:72px}.bk-hero h1{font-size:37px}.bk-hero-books>a{width:142px}.bk-cover-name{font-size:22px}.bk-hero-books .bk-cover-name{font-size:18px}.bk-hero-books>a:first-child{transform:rotate(-13deg) translate(-80px,4px)}.bk-hero-books>a:nth-child(3){transform:rotate(13deg) translate(80px,4px)}.er-topbar{gap:8px;padding-inline:12px}.er-crumbs{margin-right:auto}.er-modes{order:3;width:100%;justify-content:center}.er-modes button{flex:1;padding-inline:6px}.er-toc{display:none}.er-shell[data-toc=open] .er-toc{position:fixed;inset:calc(var(--reader-bar-height,100px) + 2px) auto 0 0;width:min(300px,82vw);height:auto;max-height:none;z-index:60;background:var(--er-surface);box-shadow:10px 0 30px #0000001a}.er-shell[data-toc=open] .er-toc-backdrop{display:block;position:fixed;inset:calc(var(--reader-bar-height,100px) + 2px) 0 0;z-index:55;background:#0005}.er-shell[data-toc=closed] .er-toc-backdrop{display:none}.er-reader{padding:42px 25px 45px}.er-topbar .er-tools{margin-left:auto}.er-crumbs{flex:1}.er-shell[data-mode=parallel] .er-layers{grid-template-columns:1fr}.er-title{font-size:33px}.page-book-detail .books-main{padding:26px 28px 50px}.ebook-hero{gap:35px;grid-template-columns:190px minmax(0,1fr)}.ebook-meta h1{font-size:30px}.bk-detail-cover .bk-cover-name{font-size:26px}}
@media(max-width:600px){.bk-content{padding:0 20px 20px}.bk-toolbar{height:66px;gap:12px}.bk-toolbar-title{font-size:10px;white-space:nowrap}.bk-search{width:auto;flex:1;height:35px;padding:0 9px;gap:7px}.bk-search input{font-size:11px}.bk-search kbd{display:none}.bk-hero{display:flex;flex-direction:column;align-items:flex-start;padding:29px 25px 0;gap:10px;min-height:0;border-radius:12px}.bk-hero-copy{position:relative;z-index:5;width:100%}.bk-hero h1{font-size:34px;letter-spacing:-1.2px;margin-top:13px}.bk-hero .bk-eyebrow{font-size:8px;letter-spacing:1.4px}.bk-hero p{font-size:11px;line-height:1.9}.bk-hero-actions{margin-top:20px;gap:13px}.bk-hero-actions>span{font-size:8px}.bk-button{font-size:10px;padding:11px 13px;gap:12px}.bk-hero-books{width:100%;height:213px;margin-top:10px}.bk-hero-books>a{width:113px}.bk-hero-books>a:first-child{transform:rotate(-13deg) translate(-68px,5px)}.bk-hero-books>a:nth-child(3){transform:rotate(13deg) translate(68px,5px)}.bk-hero-books .bk-cover{padding:13px 10px 10px 14px}.bk-hero-books .bk-cover-name{font-size:16px}.bk-hero-books .bk-cover-han{font-size:11px;letter-spacing:2px}.bk-hero-books .bk-cover-brand{font-size:4px;margin-bottom:14px;letter-spacing:1px}.bk-hero-books .bk-cover-author{font-size:6px}.bk-hero-books .bk-cover-edition{font-size:4px;letter-spacing:1px}.bk-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:24px 23px}.bk-featured .bk-grid>li:nth-child(n+5){display:none}.bk-featured{margin-top:29px}.bk-section-head h2{font-size:20px}.bk-section-head>a{font-size:9px}.bk-section-head .bk-eyebrow{font-size:7px;letter-spacing:1.2px}.bk-cover{padding:16px 13px 13px 19px}.bk-cover-name{font-size:22px}.bk-cover-brand{font-size:6px;margin-bottom:18px}.bk-cover-han{font-size:14px}.bk-cover-author{font-size:9px}.bk-cover-edition{font-size:5px}.bk-card-info{margin-top:14px;gap:5px}.bk-card-info strong{font-size:14px}.bk-card-info>span{font-size:12px}.bk-card-info small{font-size:10px}.bk-reading-note{padding:19px 0;margin:28px 0;gap:12px;align-items:flex-start}.bk-reading-note>i{margin-top:5px;font-size:18px}.bk-reading-note>span{display:none}.bk-reading-note p{font-size:11px}.bk-reading-note strong{display:block}.bk-filters{gap:4px;flex-wrap:nowrap;overflow:auto;padding-bottom:9px;scrollbar-width:thin}.bk-filters button{font-size:11px;padding-inline:11px;min-height:36px}.bk-endnote{font-size:9px;align-items:center;text-align:center}.books-footer{padding:22px 18px;font-size:10px}.books-footer-links{gap:8px 16px}.bk-catalog .bk-section-head h2{font-size:18px}.bk-resume-link{padding:16px}.bk-resume-link strong{font-size:13px}.bk-section-head>span{font-size:9px;white-space:normal;text-align:right}.page-book-detail .books-main{padding:22px 20px 40px}.ebook-hero{display:flex;flex-direction:column;gap:30px;text-align:center;margin-bottom:30px}.ebook-cover-wrap{width:175px}.ebook-meta h1{font-size:33px}.ebook-han-display{font-size:18px;margin-bottom:12px}.ebook-meta .bk-eyebrow{font-size:8px}.ebook-description{font-size:13px}.ebook-actions{justify-content:center;gap:7px}.ebook-btn-read{font-size:12px;padding:12px 16px}.ebook-btn-ghost{font-size:11px;padding:11px 12px}.ebook-facts{justify-content:center;gap:20px}.ebook-facts li{padding:0;max-width:40%}.ebook-facts strong{font-size:11px}.ebook-chapters{padding:19px 15px}.ebook-chapters-head h2{font-size:18px}.ebook-ch-list{grid-template-columns:1fr}.book-breadcrumb{margin-bottom:28px}.er-tools{gap:1px}.er-icon-btn{width:31px;height:34px}.er-crumbs{font-size:12px;min-width:50px}.er-reader{padding:34px 22px 40px}.er-title{font-size:30px}.er-chapter-header{margin-bottom:30px}.er-shell[data-mode=parallel] .er-layers{gap:8px}.er-toc-header strong{font-size:15px}.er-toc-item>a{font-size:13px;padding:12px}.er-focus-exit{right:13px;top:12px}.er-reading-status{font-size:9px}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{scroll-behavior:auto!important;transition:none!important;animation:none!important}}
.bk-mobile-nav{display:none}
@media(max-width:900px){.bk-mobile-nav{display:flex;align-items:center;gap:4px;margin:0 0 19px;border-bottom:1px solid var(--bk-line);padding-bottom:13px}.bk-mobile-nav a{display:block;color:var(--bk-muted);text-decoration:none;padding:8px 10px;border-radius:6px;font-size:11px;white-space:nowrap}.bk-mobile-nav a.is-active{background:var(--bk-soft);color:var(--bk-blue);font-weight:600}.bk-mobile-nav button{margin-left:auto;background:none;border:0;border-radius:6px;width:32px;height:32px;color:var(--bk-muted)}}
@media(min-width:901px){.er-toc,.er-shell[data-toc=open] .er-toc{display:flex;position:sticky;inset:auto;top:calc(var(--reader-bar-height,56px) + 2px);height:calc(100dvh - var(--reader-bar-height,56px) - 2px);max-height:calc(100dvh - var(--reader-bar-height,56px) - 2px)}.er-shell[data-toc=closed] .er-toc{display:none}.er-toc-backdrop{display:none!important}}
html[data-theme=dark] .bk-hero .bk-eyebrow{color:#b2c8bb}
@media(max-width:360px){.bk-content{padding-inline:15px}.bk-mobile-nav{gap:1px}.bk-mobile-nav a{padding-inline:8px}.bk-hero{padding-inline:20px}.bk-hero h1{font-size:30px}.bk-hero-actions>span{font-size:7px}.bk-toolbar-title{font-size:9px}.bk-grid{gap:22px 18px}.bk-cover-name{font-size:19px}.bk-cover-brand{font-size:5px;letter-spacing:1px}.bk-section-head h2{font-size:18px}.bk-section-head>a{font-size:8px}.er-tools .er-icon-btn{width:28px}.er-crumbs{font-size:11px}.er-reader{padding-inline:20px}}
/* QMF mounts a fixed header. Keep reader controls below it after scrolling. */
.er-topbar{top:var(--reader-header-height,64px)}
.er-progress{top:calc(var(--reader-header-height,64px) + var(--reader-bar-height,56px))}
.er-toc,.er-shell[data-toc=open] .er-toc{top:calc(var(--reader-header-height,64px) + var(--reader-bar-height,56px) + 2px);height:calc(100dvh - var(--reader-header-height,64px) - var(--reader-bar-height,56px) - 2px);max-height:calc(100dvh - var(--reader-header-height,64px) - var(--reader-bar-height,56px) - 2px)}
.er-layer{scroll-margin-top:calc(var(--reader-header-height,64px) + var(--reader-bar-height,56px) + 24px)}
@media(max-width:900px){.er-shell[data-toc=open] .er-toc,.er-shell[data-toc=open] .er-toc-backdrop{top:calc(var(--reader-header-height,64px) + var(--reader-bar-height,100px) + 2px)}}
.er-shell[data-focus=on] .er-progress{top:0}