/* Reading layer only; shared site navigation stays unchanged. */
.skip-link{position:absolute;top:-100px;left:16px}.skip-link:focus{top:8px;z-index:100;background:#fff;padding:12px}
.book-layout{max-width:840px;margin:auto;padding:36px 28px 64px}.book-layout article{font-family:"Noto Serif CJK SC","Songti SC",serif;font-size:18px;line-height:1.95;overflow-wrap:anywhere}.book-layout h1,.book-layout h2,.book-layout h3,.book-layout .edition,.book-toc{font-family:"Noto Sans CJK SC","PingFang SC","Microsoft YaHei",sans-serif}
.book-layout h1{font-size:clamp(30px,4vw,43px);line-height:1.5;color:#143550;margin:24px 0}.book-layout h2{font-size:26px;line-height:1.6;margin:52px 0 20px;color:#143550}.book-layout h3{font-size:21px;line-height:1.65;margin:32px 0 16px;color:#143550}.book-layout p{margin:0 0 22px}.book-layout [id]{scroll-margin-top:100px}.book-layout .book-subtitle{font-size:18px;color:#536774}.book-layout .book-meta,.book-layout .edition{font-size:14px;color:#596777;line-height:1.7;margin-bottom:12px}.book-layout .thesis{margin:28px 0;padding:20px 24px;border-left:4px solid #185c64;background:#f1f6f5;font-family:"Noto Sans CJK SC","PingFang SC",sans-serif;font-size:20px;font-weight:600;line-height:1.9}.book-layout .source-link,.book-layout .source-note,.book-layout .scenario-note{font-size:14px;line-height:1.85;color:#52636c}.book-layout .source-link{border-top:1px solid #e0e6e8;padding-top:15px;margin-top:30px}.book-layout .scenario-note{border-left:2px solid #adbdc3;padding-left:16px}.book-layout .landing{font-weight:bold;font-size:22px;line-height:1.8;color:#143550}.book-tools{display:flex;gap:12px;flex-wrap:wrap;margin:20px 0}.book-toc{border:1px solid #dce4e8;border-radius:8px;margin:24px 0 36px;padding:16px 20px;font-size:15px;line-height:1.85}.book-toc summary{cursor:pointer;font-weight:600}.book-toc li{padding:4px 0}.book-layout a:focus-visible,summary:focus-visible{outline:3px solid #185c64;outline-offset:3px}.back-top{margin-top:36px}.book-layout a{color:#205b70}.book-tools a.btn{color:white}.book-tools a.secondary{color:#143550}
@media(max-width:600px){.book-layout{padding:24px 20px 44px}.book-layout article{font-size:17px;line-height:1.95}.book-layout h2{font-size:23px;margin-top:40px}.book-layout h3{font-size:19px}.book-layout .thesis{font-size:18px;padding:15px 17px}.book-tools .btn{font-size:14px;padding:10px 12px}.book-toc{padding:14px 16px}.book-toc ol{padding-left:20px}}
@media print{.site-header,.site-footer,.book-tools,.book-toc,.back-top,.breadcrumbs,.skip-link{display:none!important}.book-layout{max-width:none;padding:0}.book-layout article{font-size:11pt;line-height:1.75}.book-layout h2,.book-layout h3{break-after:avoid}.book-layout p{orphans:3;widows:3}.book-layout .thesis{break-inside:avoid}}