/* 本章与 01–04 同套样式 */
.book-shell { grid-template-columns: 340px 1fr; }
.toc-scroll { padding: 12px 18px; overflow: visible; max-height: none; }
.toc-scroll .toc__title::before { content: ''; }
.toc__box { padding: 0; background: transparent; border: 0; box-shadow: none; }
.toc__title { font-weight: 700; color: var(--ink); font-size: 13px; display: flex; align-items: center; gap: 10px; padding: 10px 0 10px; margin: 0 0 10px; border-bottom: 1px solid var(--border); }
.toc__title::before { content: ''; }
.toc a { color: var(--ink); text-decoration: none !important; }
.toc a:hover { color: var(--accent-hover); }
.toc ul { list-style: none; margin: 0; padding: 0; }
.toc .lv1 { display: block; padding: 6px 0 4px; font-weight: 700; font-size: 14px; color: var(--ink); }
.toc.book-nav > li + li { margin-top: 4px; }
.toc .lv1 .n { color: var(--accent); font-weight: 900; min-width: 18px; }
.toc .lv2 { margin: 4px 0 12px 12px; padding-left: 12px; border-left: 2px solid rgba(231,229,228,0.95); display: grid; gap: 2px; }
.toc .lv2 a { display: flex; gap: 8px; padding: 5px 0; color: var(--ink-light); font-size: 12px; border-radius: 0; }
.toc .lv2 .n { color: var(--ink-muted); font-weight: 800; min-width: 26px; }
.toc a.is-active { color: var(--accent-hover); font-weight: 700; }
.toc .lv2 a.is-active { position: relative; }
.toc .lv2 a.is-active::before { content: ''; position: absolute; left: -14px; top: 6px; width: 2px; height: calc(100% - 12px); background: var(--accent); border-radius: 1px; }
.article { padding: 0; }
.callout { border-left: 3px solid var(--accent); padding: 10px 12px; margin: 12px 0 16px; background: transparent; }
.cols { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.card { border: 1px solid rgba(231,229,228,0.9); background: rgba(255,255,255,0.86); border-radius: 14px; padding: 12px; box-shadow: var(--shadow-sm); }
.card .t { font-weight: 700; margin-bottom: 6px; }
.card .d { color: var(--ink-light); font-size: 13px; }
.copy-btn { position: absolute; top: 8px; right: 8px; border: 1px solid #e5e5e5; background: #fff; color: var(--ink); border-radius: 6px; padding: 4px 8px; font-size: 12px; cursor: pointer; box-shadow: none; }
.copy-btn:hover { background: #f7f7f7; }
.copy-btn[data-state="ok"] { border-color: rgba(13,148,136,0.35); color: var(--accent-hover); }
.book-main pre code.hljs { padding: 0; background: transparent; }
.book-main .hljs-keyword, .book-main .hljs-selector-tag, .book-main .hljs-addition { color: var(--accent-hover); font-weight: 600; }
.book-main .hljs-string, .book-main .hljs-attr { color: #0d6e66; }
.book-main .hljs-comment { color: var(--ink-muted); font-style: italic; }
.book-main .hljs-number, .book-main .hljs-literal { color: #b45309; }
.book-main .hljs-built_in, .book-main .hljs-title.function_ { color: var(--ink); }
.book-main .hljs-title.class_ { color: var(--accent); }
@media (max-width: 980px) { .book-shell { grid-template-columns: 1fr; } }
@media (max-width: 900px) { .cols { grid-template-columns: 1fr; } }