.study-content{min-width:0}.study-tabs{display:flex;height:44px;border-bottom:1px solid var(--hn-line);gap:20px;margin-bottom:20px}.hn-page .study-tabs button{border:0;border-radius:0;background:var(--hn-canvas);color:var(--hn-muted);padding:0 4px;min-height:44px}.hn-page .study-tabs button[aria-selected=true]{color:var(--hn-accent);border-bottom:2px solid var(--hn-accent);font-weight:600}.study-current-chapter{border-bottom:1px solid var(--hn-line-soft)}.study-current-chapter>summary{display:flex;gap:12px;list-style:none;padding:12px 8px;font-size:17px;cursor:pointer;background:var(--hn-selected)}.study-current-chapter>summary::-webkit-details-marker{display:none}.study-current-chapter>summary:after{content:"−";margin-left:auto;color:var(--hn-muted)}.study-current-chapter:not([open])>summary:after{content:"+"}.study-current-chapter summary span,.study-chapter-link span{flex-shrink:0;font-size:var(--hn-small);color:var(--hn-muted);padding-top:1px}.study-toc{padding:12px 0 20px 16px}.hn-page .study-toc a{display:block;text-decoration:none;font-size:var(--hn-small);line-height:1.7;color:var(--hn-muted);padding:7px 10px;border-left:2px solid var(--hn-line-soft);overflow-wrap:anywhere}.hn-page .study-toc a.study-toc-sub{padding-left:20px}.hn-page .study-toc a[aria-current]{color:var(--hn-accent-deep);background:var(--hn-accent-soft);border-color:var(--hn-accent);font-weight:600}.hn-page .study-chapter-link{display:flex;gap:12px;padding:16px 8px;text-decoration:none;color:var(--hn-ink);border-bottom:1px solid var(--hn-line-soft);font-size:17px}.study-chapter-link strong{font-weight:500}.study-lead{max-width:720px;color:var(--hn-ink-soft);line-height:1.9;margin-bottom:40px;overflow-wrap:anywhere}.study-home{padding-bottom:0}.study-branches{display:grid;gap:40px}.study-branches h2{font:600 25px/1.6 var(--hn-serif);margin-bottom:12px}.study-section-description{color:var(--hn-muted);margin-bottom:24px}.study-chapter-list{list-style:none;padding:0}.study-chapter-list li{border-top:1px solid var(--hn-line)}.study-chapter-list li:last-child{border-bottom:1px solid var(--hn-line)}.hn-page .study-chapter-list a{display:grid;grid-template-columns:2em minmax(0,1fr) auto;gap:16px;padding:22px 0;line-height:1.65;text-decoration:none}.study-chapter-list strong{text-decoration:underline;text-underline-offset:4px}.study-chapter-summary{display:block;color:var(--hn-ink-soft);font-size:var(--hn-small);margin:8px 0}.study-chapter-number,.study-meta{color:var(--hn-muted);font-size:var(--hn-small)}.study-chapter-end{max-width:720px}.study-prose{font-size:var(--hn-body);line-height:1.95;color:var(--hn-ink-soft);overflow-wrap:anywhere}.study-prose>p,.study-prose>ul,.study-prose>ol{margin-bottom:22px}.study-prose h2{font:600 25px/1.6 var(--hn-serif);border-top:1px solid var(--hn-line-soft);padding-top:28px;margin:40px 0 24px;color:var(--hn-ink)}.study-prose h2:first-child{margin-top:0}.study-prose h3{font-size:19px;margin:30px 0 16px;color:var(--hn-ink)}.study-prose h4{margin:1.8em 0 .8em}.study-prose [id]{scroll-margin-top:92px}.study-prose :target{background-color:var(--hn-warm)}.study-prose ul,.study-prose ol{padding-left:1.4em}.study-prose li{margin-bottom:.6em}.study-prose li>p{margin-bottom:.6em}.study-prose blockquote{border-left:2px solid var(--hn-line);margin:24px 0;padding:16px 20px;background:var(--hn-warm);font-size:var(--hn-body)}.study-prose blockquote p+p{margin-top:.8em}.study-prose .study-original{font-family:var(--hn-hanzi);font-size:1.4em;line-height:2;letter-spacing:.06em;white-space:pre-line}.study-prose blockquote cite{font-family:var(--hn-sans);font-size:var(--hn-small)}.study-prose hr{border:0;border-top:1px solid var(--hn-line);margin:2.5em 0}.study-prose code{font-size:var(--hn-small);background:var(--hn-selected);padding:.1em .25em;border-radius:3px;white-space:pre-wrap}.study-prose pre{max-width:100%;overflow-x:auto;padding:1em;margin:1.5em 0}.study-table-scroll{width:100%;max-width:100%;overflow-x:auto;margin:1.8em 0;scrollbar-width:thin;-webkit-overflow-scrolling:touch}.study-table-scroll::-webkit-scrollbar{display:block;height:8px}.study-table-scroll::-webkit-scrollbar-thumb{background:var(--hn-line);border-radius:4px}.study-prose table{border-collapse:collapse;width:100%;min-width:48em;font-size:var(--hn-small);line-height:1.8}.study-prose th,.study-prose td{min-width:10em;padding:.7em .8em;border:1px solid var(--hn-line);vertical-align:top;word-break:keep-all;overflow-wrap:normal}.study-prose td code{white-space:nowrap}.study-prose th{background:var(--hn-selected);text-align:left;font-weight:600}.study-prose .study-citation{font-size:var(--hn-small);white-space:nowrap}.study-prose .study-source{font-size:var(--hn-small);line-height:1.9;margin-bottom:1.4em}.study-backlinks{display:block;font-size:var(--hn-small);color:var(--hn-muted)}.study-backlinks a{display:inline-block;padding:2px 4px}.study-chapter-end{margin-top:3em;padding-top:2em;border-top:1px solid var(--hn-line)}.study-pagination{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:24px;font-size:var(--hn-small)}.study-pagination a:last-child{text-align:right}.study-pagination span,.study-pagination strong{display:block}.study-pagination span{color:var(--hn-muted);margin-bottom:6px}.study-write-link{display:block;margin:2em 0;padding:18px;text-align:center;color:var(--hn-accent);background:var(--hn-selected)}@media(max-width:900px){.study-prose [id]{scroll-margin-top:140px}.study-prose h2{font-size:24px}.study-pagination{grid-template-columns:minmax(0,1fr);gap:16px}.study-pagination a:last-child{text-align:left}}