:root{--bg:#ffffff;--bg-alt:#f1f3f4;--fg:#202124;--fg-muted:#5f6368;--accent:#1a73e8;--accent-soft:rgba(26,115,232,0.08);--border:#dadce0;--card-bg:#ffffff;--reader-font-size:17px;--line-height:1.9;--sidebar-w:15rem;--header-h:3.5rem;--scrollbar:10px}html.dark{--bg:#202124;--bg-alt:#292a2d;--fg:#e8eaed;--fg-muted:#9aa0a6;--accent:#8ab4f8;--accent-soft:rgba(138,180,248,0.12);--border:#3c4043;--card-bg:#292a2d}*{box-sizing:border-box}html{scrollbar-gutter:stable}*{scrollbar-width:thin;scrollbar-color:var(--border) transparent}::-webkit-scrollbar{width:var(--scrollbar);height:var(--scrollbar)}::-webkit-scrollbar-track{background:transparent}::-webkit-scrollbar-thumb{background:var(--border);border-radius:calc(var(--scrollbar) / 2);border:2px solid var(--bg)}::-webkit-scrollbar-thumb:hover{background:var(--accent)}::-webkit-scrollbar-corner{background:transparent}body{margin:0;background:var(--bg);color:var(--fg);font-family:"Clear Han Serif","Noto Serif SC","Source Han Serif SC","Songti 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1.2rem;background:var(--bg-alt);border-bottom:1px solid var(--border)}.brand{font-size:1.15rem;font-weight:700;color:var(--accent);text-decoration:none;letter-spacing:0.05em}.header-tools{display:flex;gap:0.4rem}.tool-btn{width:2.1rem;height:2.1rem;border:1px solid var(--border);border-radius:6px;background:var(--card-bg);color:var(--fg);font-size:0.9rem;cursor:pointer;transition:border-color 0.2s,color 0.2s}.tool-btn:hover{border-color:var(--accent);color:var(--accent)}.tool-btn:disabled{opacity:0.4;cursor:default}.container{max-width:46rem;margin:0 auto;padding:2rem 1.2rem 4rem;font-size:var(--reader-font-size)}.breadcrumb{font-size:0.9rem;color:var(--fg-muted);margin-bottom:1.4rem}.breadcrumb a{color:var(--accent);text-decoration:none}.breadcrumb a:hover{text-decoration:underline}.breadcrumb .sep{margin:0 0.4rem}.page-title{font-size:1.9rem;margin:0.4rem 0 0.3rem}.page-subtitle{color:var(--fg-muted);margin:0 0 2rem}.shelf{display:grid;grid-template-columns:repeat(auto-fill,minmax(10.5rem,1fr));gap:0.65rem}.book-card{display:block;padding:0.85rem 0.95rem;background:var(--card-bg);border:1px solid var(--border);border-radius:8px;text-decoration:none;color:var(--fg);transition:transform 0.15s ease,box-shadow 0.2s ease,border-color 0.2s}.book-card:hover{transform:translateY(-2px);border-color:var(--accent);box-shadow:0 6px 18px rgba(0,0,0,0.08)}.book-card-title{margin:0 0 0.35rem;font-size:1.02rem;color:var(--accent)}.book-card-meta{margin:0 0 0.45rem;color:var(--fg-muted);font-size:0.8rem}.book-card-cta{font-size:0.8rem;color:var(--accent)}.book-title{font-size:2rem;margin:0.3rem 0 0.4rem}.book-meta{color:var(--fg-muted);margin:0 0 1rem}.book-tools{width:auto;padding:0 0.8rem;margin-bottom:1rem}.toc{list-style:none;margin:0;padding:0;border-top:1px solid var(--border)}.toc li{display:flex;align-items:baseline;gap:0.9rem;padding:0.75rem 0.4rem;border-bottom:1px solid var(--border)}.toc li.toc-item>.toc-expand{flex:none;width:1.4rem;height:1.4rem;border:1px solid var(--border);border-radius:4px;background:var(--card-bg);color:var(--fg-muted);font-size:0.7rem;line-height:1;cursor:pointer;align-self:center;transition:transform 0.2s,border-color 0.2s,color 0.2s}.toc li.toc-item>.toc-expand:hover{border-color:var(--accent);color:var(--accent)}.toc li.toc-item.expanded>.toc-expand{transform:rotate(90deg)}.toc-num{flex:0 0 2.6rem;text-align:right;color:var(--fg-muted);font-size:0.85rem;font-variant-numeric:tabular-nums}.toc a{color:var(--fg);text-decoration:none;line-height:1.6}.toc a:hover{color:var(--accent)}.toc-subs{list-style:none;margin:0.4rem 0 0.2rem;padding-left:1.2rem;border-left:1px solid var(--border)}.toc-subs li{display:block;padding:0.35rem 0.3rem;border:none}.toc-subs a{font-size:0.92em;color:var(--fg-muted)}.toc-subs a::before{content:"";display:inline-block;width:4px;height:4px;margin-right:0.45rem;border-radius:50%;background:var(--border);vertical-align:middle}.toc-subs li.level-2 a::before{background:var(--accent);opacity:0.55}.toc-subs li.level-3{padding-left:1.1rem}.toc-subs li.level-3 a{font-size:0.88em}.toc-subs li.level-3 a::before{width:3px;height:3px}.toc-subs a:hover{color:var(--accent)}.chapter-title{font-size:1.55rem;line-height:1.5;margin:0.2rem 0 1.6rem;text-align:center}.prose{line-height:var(--line-height);word-break:break-word}.prose p{margin:0 0 1.1em;text-align:justify;text-indent:2em}.prose h2,.prose h3,.prose h4{line-height:1.5;margin:1.8em 0 0.8em;color:var(--accent);scroll-margin-top:4rem}.prose img{max-width:100%;height:auto;display:block;margin:1.2em auto;border-radius:4px;cursor:zoom-in}.prose blockquote{margin:1.2em 0;padding:0.4em 1em;border-left:3px solid var(--accent);background:var(--accent-soft);color:var(--fg-muted)}.prose table{border-collapse:collapse;width:100%;margin:1.2em 0;font-size:0.95em}.prose th,.prose td{border:1px solid var(--border);padding:0.5em 0.7em;text-align:left}.prose th{background:var(--bg-alt)}.prose code{background:var(--bg-alt);padding:0.15em 0.4em;border-radius:4px;font-size:0.9em}.prose pre{background:var(--bg-alt);padding:1em;border-radius:6px;overflow-x:auto;line-height:1.6}.pager{display:flex;justify-content:space-between;gap:1rem;margin-top:3rem;padding-top:1.4rem;border-top:1px solid var(--border)}.pager-link{display:flex;align-items:center;gap:0.7rem;max-width:45%;padding:0.7rem 1rem;border:1px solid var(--border);border-radius:8px;background:var(--card-bg);color:var(--fg);text-decoration:none;transition:border-color 0.2s,color 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var(--border)}.toc-side-title{font-weight:700;color:var(--accent);letter-spacing:0.05em}.toc-side-actions{display:flex;gap:0.4rem}.toc-close-btn{display:none}.toc-collapse-btn{display:none}.bm-toggle{color:var(--fg-muted)}.bm-toggle.active{color:#e8b43a;border-color:#e8b43a}html.dark .bm-toggle.active{color:#f0c94e}.bm-list-wrap{flex:none;max-height:32%;overflow-y:auto;border-top:1px solid var(--border);padding:0.5rem 0.6rem 0.8rem;font-size:0.9rem}.bm-head{font-weight:700;color:var(--accent);margin:0 0 0.4rem;letter-spacing:0.05em}.bm-empty{color:var(--fg-muted);margin:0}.bm-list{list-style:none;margin:0;padding:0}.bm-item{display:flex;align-items:center;gap:0.3rem;padding:0.2rem 0}.bm-link{flex:1;min-width:0;display:block;padding:0.3rem 0.4rem;border-radius:4px;border-left:2px solid transparent;color:var(--fg);text-decoration:none;line-height:1.45}.bm-link:hover{background:var(--accent-soft)}.bm-item.current-book .bm-link{border-left-color:var(--accent)}.bm-book{display:block;font-size:0.78em;color:var(--fg-muted)}.bm-chapter{display:block;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.bm-pos{color:var(--accent);font-size:0.8em;margin-top:0.1rem}.bm-del{flex:none;width:1.3rem;height:1.3rem;border:none;border-radius:4px;background:transparent;color:var(--fg-muted);cursor:pointer;font-size:0.85rem;line-height:1}.bm-del:hover{color:#d64545;background:var(--accent-soft)}.toc-side-body{flex:1;overflow-y:auto;overflow-x:hidden;padding:0.8rem 0.6rem 2rem}.toc-loading{color:var(--fg-muted);padding:0 0.4rem}.toc-tree{list-style:none;margin:0;padding:0}.toc-tree .toc-book{font-weight:700;margin:0 0.4rem 0.8rem;color:var(--accent);font-size:1.05em}.toc-tree ul{list-style:none;margin:0;padding-left:0.9rem}.toc-tree a{display:block;padding:0.35rem 0.4rem;border-radius:4px;color:var(--fg);text-decoration:none;line-height:1.5;border-left:2px solid transparent}.toc-tree a:hover{color:var(--accent);background:var(--accent-soft)}.toc-tree .toc-ch>.toc-ch-row>a{font-weight:600}.toc-tree .toc-ch.current>.toc-ch-row>a{color:var(--accent);background:var(--accent-soft);border-left-color:var(--accent)}.toc-tree .toc-sub.level-3 a{padding-left:1rem;font-size:0.9em;color:var(--fg-muted)}.toc-tree .toc-sub.level-3 a:hover{color:var(--accent)}.toc-ch-row{display:flex;align-items:baseline;gap:0.3rem}.toc-toggle-subs{flex:none;width:1rem;text-align:center;color:var(--fg-muted);font-size:0.75rem;cursor:pointer;user-select:none;transition:transform 0.2s;align-self:center}.toc-toggle-subs:hover{color:var(--accent)}.toc-ch.open>.toc-ch-row .toc-toggle-subs{transform:rotate(90deg)}.toc-sub-list{list-style:none;margin:0 0 0 0.5rem;padding-left:0.9rem;border-left:1px solid var(--border);display:none}.toc-sub-list.open{display:block}.toc-ch.open>.toc-sub-list{display:block}.toc-tree .toc-sub a{position:relative}.toc-tree .toc-sub a::before{content:"";display:inline-block;width:4px;height:4px;margin-right:0.45rem;border-radius:50%;background:var(--border);vertical-align:middle}.toc-tree .toc-sub.level-2 a::before{background:var(--accent);opacity:0.55}.toc-tree .toc-sub.level-3 a{padding-left:1.1rem;font-size:0.9em;color:var(--fg-muted)}.toc-tree .toc-sub.level-3 a::before{width:3px;height:3px}.toc-tree .toc-sub.level-3 a:hover{color:var(--accent)}.fab{position:fixed;right:1.2rem;z-index:35;width:2.9rem;height:2.9rem;border:1px solid var(--border);border-radius:50%;background:var(--card-bg);color:var(--accent);font-size:1.05rem;line-height:1;cursor:pointer;box-shadow:0 4px 14px rgba(0,0,0,0.16);transition:transform 0.15s ease,border-color 0.2s,box-shadow 0.2s}.fab:hover{border-color:var(--accent);transform:translateY(-2px);box-shadow:0 6px 18px rgba(0,0,0,0.2)}.fab-top{bottom:1.2rem}.fab-toc{display:none}.fab-reopen{display:none}.lightbox{position:fixed;inset:0;z-index:60;background:rgba(0,0,0,0.92);display:flex;align-items:center;justify-content:center;opacity:0;transition:opacity 0.2s ease}.lightbox.show{opacity:1}.lightbox-main{max-width:94vw;max-height:92vh;border-radius:4px;box-shadow:0 10px 40px rgba(0,0,0,0.5)}.lightbox-btn{position:absolute;width:3rem;height:3rem;border:none;border-radius:50%;background:rgba(255,255,255,0.12);color:#fff;font-size:1.6rem;line-height:1;cursor:pointer;transition:background 0.2s;z-index:1}.lightbox-btn:hover{background:rgba(255,255,255,0.28)}.lightbox-close{top:1rem;right:1rem;font-size:1.8rem}.lightbox-prev{left:1rem;top:50%;transform:translateY(-50%)}.lightbox-next{right:1rem;top:50%;transform:translateY(-50%)}.site-footer{text-align:center;color:var(--fg-muted);font-size:0.85rem;padding:1.5rem 1rem 2.5rem;border-top:1px solid var(--border)}@media (min-width:1100px){.container.reading{margin-left:calc(var(--sidebar-w) + max(0px,calc((100vw - var(--sidebar-w) - 46rem) / 2)));margin-right:auto}.toc-close-btn,.toc-backdrop,.fab-toc{display:none}.toc-collapse-btn{display:inline-block}html.sidebar-collapsed .toc-side{transform:translateX(-102%)}html.sidebar-collapsed .container.reading{margin-left:auto}.fab-reopen{display:none;left:0.8rem;right:auto;bottom:auto;top:calc(var(--header-h) + 0.8rem)}html.sidebar-collapsed .fab-reopen{display:block}}@media (max-width:1099.98px){.toc-side{transform:translateX(-102%);box-shadow:8px 0 24px rgba(0,0,0,0.15)}.toc-side.open{transform:translateX(0)}.toc-close-btn{display:inline-block}.fab-toc{display:block;bottom:5.4rem}}@media (max-width:520px){.container{padding:1.2rem 0.9rem 3rem}.pager{flex-direction:column}.pager-link,.pager-link.next{max-width:100%;margin-left:0}}