.topics-page{--paper:#f5f2eb;--ink:#262c28;--soft:#59645d;--line:#cdcfc5;--accent:#bb4b32;--green:#365947}
.topics-page *{box-sizing:border-box}
.topics-page{scroll-behavior:smooth}
.topics-page{margin:0;background:var(--paper);color:var(--ink);font-family:"PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;line-height:1.75}
.topics-page a{color:inherit;text-decoration:none}
.topics-page a:hover{color:var(--accent)}
.topics-page a:focus-visible,.topics-page button:focus-visible{outline:2px solid var(--accent);outline-offset:5px}
.topics-page.wrap{width:min(1180px,calc(100% - 96px));margin:auto}
.topics-page .mast{display:flex;align-items:center;justify-content:space-between;height:86px;border-bottom:1px solid var(--ink)}
.topics-page .brand{font-weight:700;letter-spacing:2px;font-size:20px}
.topics-page .brand small{font-size:10px;letter-spacing:3px;display:block;line-height:1.2}
.topics-page .nav{display:flex;gap:28px;font-size:14px}
.topics-page .active{color:var(--accent)}
.topics-page .hero{display:grid;grid-template-columns:1.5fr 1fr;gap:90px;padding:75px 0 58px;align-items:end}
.topics-page .eyebrow{font-size:12px;letter-spacing:2px;color:var(--accent);margin:0 0 17px}
.topics-page h1{font-family:"Songti SC","STSong",serif;font-weight:600;font-size:clamp(38px,4.8vw,66px);line-height:1.22;letter-spacing:-1px;margin:0}
.topics-page h1 em{font-style:normal;color:var(--green)}
.topics-page .hero p{margin:0;color:var(--soft);font-size:16px;max-width:490px}
.topics-page .feature{display:grid;grid-template-columns:.95fr 1.4fr;background:#e4e9df;padding:42px 44px;gap:70px;border-top:3px solid var(--green)}
.topics-page .feature h2{font-size:34px;font-family:"Songti SC","STSong",serif;line-height:1.4;margin:10px 0 16px}
.topics-page .feature p{color:#425347;font-size:15px;margin:0 0 23px;max-width:420px}
.topics-page .meta{font-size:12px;color:var(--soft)}
.topics-page .cta{display:inline-block;border-bottom:1px solid currentColor;font-size:14px;font-weight:600;padding-bottom:4px}
.topics-page .start{border-left:1px solid #b6c2b1;padding-left:36px}
.topics-page .start-title{font-size:12px;color:var(--soft);margin-bottom:15px}
.topics-page .start a{display:flex;gap:19px;padding:14px 0;border-bottom:1px solid #c0ccba;font-size:16px}
.topics-page .start a:last-child{border-bottom:0}
.topics-page .num{font-size:12px;color:var(--accent);padding-top:4px;flex-shrink:0}
.topics-page .start small{display:block;color:var(--soft);font-size:12px;margin-top:3px}
.topics-page .section-head{display:flex;align-items:baseline;justify-content:space-between;padding:59px 0 24px}
.topics-page .section-head h2{font-size:23px;margin:0}
.topics-page .section-head p{font-size:12px;color:var(--soft);margin:0}
.topics-page .topic-row{display:grid;grid-template-columns:54px 1fr 1.1fr 30px;gap:24px;align-items:start;padding:28px 0;border-top:1px solid var(--line)}
.topics-page .topic-row h3{font-size:23px;line-height:1.5;margin:0 0 4px}
.topics-page .topic-row .copy{font-size:14px;color:var(--soft);margin:0}
.topics-page .topic-row .tag{font-size:12px;color:var(--green)}
.topics-page .topic-row .arrow{font-size:23px;transition:transform .15s}
.topics-page .topic-row:hover .arrow{transform:translateX(4px)}
.topics-page .principle{display:grid;grid-template-columns:1fr 2fr;gap:80px;border-top:1px solid var(--ink);padding:32px 0;margin-top:26px}
.topics-page .principle h2{font-size:20px;margin:0}
.topics-page .principle p{font-size:14px;color:var(--soft);margin:0}
.topics-page .foot{border-top:1px solid var(--line);display:flex;justify-content:space-between;padding:25px 0;font-size:12px;color:var(--soft)}
.topics-page .crumb{font-size:13px;color:var(--soft);padding-top:28px}
.topics-page .detail-hero{padding:40px 0 35px;max-width:850px}
.topics-page .detail-hero h1{font-size:clamp(32px,4vw,52px)}
.topics-page .detail-hero p{max-width:690px;color:var(--soft);font-size:17px}
.topics-page .stages-nav{display:flex;gap:28px;flex-wrap:wrap;border-block:1px solid var(--line);padding:17px 0;font-size:14px}
.topics-page .stage{display:grid;grid-template-columns:240px 1fr;gap:50px;padding-top:45px;scroll-margin-top:20px}
.topics-page .stage-head h2{font-size:22px;margin:5px 0}
.topics-page .article{display:block;border-bottom:1px solid var(--line);padding:0 0 22px;margin-bottom:24px}
.topics-page .article h3{font-size:19px;line-height:1.65;margin:6px 0 8px;font-weight:600}
.topics-page .article p{color:var(--soft);font-size:14px;line-height:1.85;margin:0}
.topics-page .access{color:var(--green);margin-left:12px}
.topics-page .note{font-size:12px;color:var(--soft);margin-top:18px}
.topics-page .preview-note{font-size:11px;border-bottom:1px solid var(--line);padding:8px 0;color:var(--soft)}
@media (max-width:760px){.topics-page.wrap{width:calc(100% - 40px)}
.topics-page .mast{height:73px}
.topics-page .nav{gap:17px;font-size:13px}
.topics-page .hero{grid-template-columns:1fr;gap:22px;padding:45px 0 35px}
.topics-page .hero p{font-size:15px}
.topics-page .feature{grid-template-columns:1fr;padding:26px 23px;gap:23px}
.topics-page .feature h2{font-size:28px}
.topics-page .start{border-left:0;border-top:1px solid #b6c2b1;padding:18px 0 0}
.topics-page .topic-row{grid-template-columns:28px 1fr 20px;gap:12px;padding:24px 0}
.topics-page .topic-row h3{font-size:21px}
.topics-page .topic-row .copy{grid-column:2;grid-row:2}
.topics-page .topic-row .arrow{grid-column:3;grid-row:1}
.topics-page .section-head{padding:39px 0 18px;display:block}
.topics-page .section-head p{margin-top:7px}
.topics-page .principle{grid-template-columns:1fr;gap:12px;padding:25px 0}
.topics-page .foot{display:block}
.topics-page .foot span{display:block;margin-top:5px}
.topics-page .stage{grid-template-columns:1fr;gap:12px;padding-top:33px}
.topics-page .stage-head h2{font-size:23px}
.topics-page .article h3{font-size:18px}
.topics-page .detail-hero{padding-top:25px}
.topics-page .stages-nav{gap:10px 22px}
.topics-page .detail-hero p{font-size:15px}
}
@media (prefers-reduced-motion:reduce){.topics-page{scroll-behavior:auto}
.topics-page .topic-row .arrow{transition:none}
}
.topics-page{--paper:#f7f5ef;--ink:#252d29;--soft:#5b665e;--line:#d7d9cd;--accent:#466341}
.topics-page .mast{height:76px}
.topics-page .preview-note{font-size:10px}
.topics-page .visual-intro{display:flex;justify-content:space-between;align-items:end;padding:40px 0 30px;gap:28px}
.topics-page .visual-intro .eyebrow{margin-bottom:10px;font-size:11px}
.topics-page .visual-intro h1{font-size:clamp(30px,3.4vw,43px);font-family:"PingFang SC","Microsoft YaHei",sans-serif;font-weight:650;letter-spacing:-1px}
.topics-page .visual-intro p:last-child{font-size:14px;color:var(--soft);margin:0 0 5px}
.topics-page .visual-feature{display:grid;grid-template-columns:.82fr 1.18fr;background:#243c30;border-radius:16px;overflow:hidden;color:#f6f6e9;min-height:340px}
.topics-page .visual-feature:hover{color:#f6f6e9}
.topics-page .feature-copy{padding:35px 42px;display:flex;flex-direction:column;align-items:start}
.topics-page .feature-kicker{font-size:12px;color:#d6e79f}
.topics-page .feature-copy h2{font-size:40px;line-height:1.26;letter-spacing:-1px;margin:16px 0 13px}
.topics-page .feature-copy p{font-size:15px;line-height:1.8;margin:0 0 24px;color:#d3ddcd}
.topics-page .feature-cta{font-size:14px;background:#dfea9a;color:#243c30;padding:10px 18px;border-radius:6px;display:flex;gap:35px;margin-top:auto}
.topics-page .feature-cta b{font-size:19px;line-height:1.1}
.topics-page .feature-graphic{background:#dfea9a;display:flex;flex-direction:column;justify-content:center;min-width:0;padding:8px 22px 20px}
.topics-page .topic-art{display:block;width:100%;height:auto;object-fit:cover}
.topics-page .feature-graphic .topic-art{max-height:295px;object-fit:contain}
.topics-page .route-mini{display:flex;align-items:center;gap:8px;font-size:11px;color:#425b43;line-height:1.4}
.topics-page .route-mini span{background:#f1f2e8;padding:5px 8px;border-radius:4px}
.topics-page .route-mini i{font-style:normal;color:#727d70}
.topics-page .feature-graphic .route-mini{justify-content:center}
.topics-page .feature-graphic .route-mini span{background:#f3f6cf;color:#294733;padding:7px 15px}
.topics-page .visual-section-head{display:flex;justify-content:space-between;align-items:center;padding:34px 0 18px}
.topics-page .visual-section-head h2{font-size:21px;line-height:1.4;margin:0}
.topics-page .visual-section-head>span{font-size:12px;color:var(--soft)}
.topics-page .visual-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:25px 24px}
.topics-page .visual-topic{min-width:0;display:block}
.topics-page .art-frame{overflow:hidden;border-radius:10px;background:#ebece2;position:relative}
.topics-page .art-frame img{aspect-ratio:600/350;object-fit:cover;transition:transform .25s ease}
.topics-page .visual-topic:hover img{transform:scale(1.025)}
.topics-page .topic-copy{padding:15px 1px 10px}
.topics-page .card-meta{display:flex;justify-content:space-between;gap:12px;color:var(--soft);font-size:11px}
.topics-page .topic-copy h3{font-size:22px;line-height:1.45;margin:8px 0 7px;letter-spacing:-.5px}
.topics-page .topic-copy h3>span{float:right;font-size:20px;color:var(--soft)}
.topics-page .topic-copy p{font-size:13px;color:var(--soft);margin:0 0 16px}
.topics-page .visual-wide{grid-column:1/-1;display:grid;grid-template-columns:1.6fr 1fr;gap:35px;align-items:center;border-block:1px solid var(--line);padding:22px 0}
.topics-page .visual-wide .art-frame img{aspect-ratio:2.8/1}
.topics-page .visual-wide .topic-copy{padding:0 20px 0 0}
.topics-page .visual-wide h3{font-size:27px;margin-top:15px}
.topics-page .visual-wide .route-mini{margin-top:23px}
.topics-page .art-caption{position:absolute;bottom:10px;left:12px;font-size:10px;background:#f8f8ed;color:#29332c;padding:4px 7px}
.topics-page .visual-end{display:flex;justify-content:space-between;gap:20px;align-items:center;border-top:1px solid var(--line);padding:28px 0;margin-top:30px;font-size:14px}
.topics-page .visual-end span{font-size:12px;color:var(--soft)}
.topics-page .visual-detail{display:grid;grid-template-columns:1fr 1fr;gap:45px;align-items:center;padding:30px 0 35px}
.topics-page .visual-detail h1{font-size:clamp(30px,3.5vw,42px);line-height:1.35;font-family:"PingFang SC","Microsoft YaHei",sans-serif}
.topics-page .visual-detail p:not(.eyebrow){font-size:15px;line-height:1.9;color:var(--soft);max-width:520px}
.topics-page .detail-art{border-radius:12px;overflow:hidden}
.topics-page .detail-art .topic-art{aspect-ratio:600/350;object-fit:cover}
.topics-page .path-map{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;border-block:1px solid var(--line);padding:23px 0}
.topics-page .path-map a{display:flex;align-items:center;gap:14px;position:relative}
.topics-page .path-map a:not(:last-child):after{content:"→";position:absolute;right:0;color:#a1ab9d}
.topics-page .path-dot{border:1px solid #b1bca7;width:39px;height:39px;display:grid;place-items:center;border-radius:50%;background:#e9eddc;font-size:12px;flex-shrink:0}
.topics-page .path-map strong{font-weight:550;font-size:14px}
.topics-page .path-map small{display:block;color:var(--soft);font-size:11px}
.topics-page .stage{padding-top:38px}
.topics-page .stage-head{border-left:3px solid #8c9f7e;padding-left:18px;align-self:start}
.topics-page .article h3{font-size:18px}
.topics-page .article p{font-size:13px}
@media (max-width:950px) and (min-width:701px){.topics-page.wrap{width:calc(100% - 48px)}
.topics-page .visual-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
.topics-page .feature-copy{padding:28px}
.topics-page .feature-copy h2{font-size:33px}
.topics-page .route-mini{gap:5px}
.topics-page .path-map{gap:10px}
.topics-page .path-map a:not(:last-child):after{content:none}
.topics-page .path-map strong{font-size:12px}
}
@media (max-width:700px){.topics-page.wrap{width:calc(100% - 32px)}
.topics-page .mast{height:67px}
.topics-page .visual-intro{display:block;padding:28px 0 23px}
.topics-page .visual-intro h1{font-size:29px;letter-spacing:-.6px}
.topics-page .visual-intro p:last-child{margin-top:12px;font-size:13px}
.topics-page .visual-feature{grid-template-columns:1fr;min-height:0;border-radius:12px}
.topics-page .feature-copy{padding:25px 26px;display:grid;grid-template-columns:1fr auto;gap:0 12px}
.topics-page .feature-kicker{grid-column:1/-1}
.topics-page .feature-copy h2{font-size:31px;margin:13px 0 10px}
.topics-page .feature-copy p{font-size:13px;grid-column:1;margin:0}
.topics-page .feature-cta{grid-column:2;grid-row:2/4;align-self:end;gap:13px;padding:9px 12px;font-size:12px;white-space:nowrap}
.topics-page .feature-graphic{padding:0 12px 18px}
.topics-page .feature-graphic .topic-art{max-height:218px}
.topics-page .feature-graphic .route-mini span{font-size:11px;padding:5px 10px}
.topics-page .visual-section-head{padding:28px 0 15px;display:block}
.topics-page .visual-section-head h2{font-size:20px}
.topics-page .visual-section-head>span{display:block;margin-top:5px;font-size:11px}
.topics-page .visual-grid{grid-template-columns:1fr;gap:22px}
.topics-page .visual-wide{grid-column:auto;display:block;padding:0;border:0}
.topics-page .visual-wide .art-frame img{aspect-ratio:1.72/1}
.topics-page .visual-wide .topic-copy{padding:15px 1px 10px}
.topics-page .visual-wide h3{font-size:22px;margin:8px 0 7px}
.topics-page .visual-wide .route-mini{margin-top:0}
.topics-page .topic-copy h3{font-size:22px}
.topics-page .visual-topic{border-bottom:1px solid var(--line);padding-bottom:15px}
.topics-page .topic-copy{padding-bottom:0}
.topics-page .art-frame img{aspect-ratio:1.8/1}
.topics-page .visual-end{display:block;padding:21px 0;margin-top:16px}
.topics-page .visual-end span{display:block;margin-top:8px}
.topics-page .visual-detail{grid-template-columns:1fr;gap:14px;padding:22px 0}
.topics-page .visual-detail h1{font-size:29px}
.topics-page .visual-detail p:not(.eyebrow){font-size:14px;margin-bottom:4px}
.topics-page .detail-art .topic-art{max-height:210px;object-fit:cover}
.topics-page .path-map{grid-template-columns:1fr;padding:20px 0;gap:20px}
.topics-page .path-map a:not(:last-child):after{content:"";width:1px;height:20px;top:39px;left:19px;background:#b1bca7}
.topics-page .path-map strong{font-size:15px}
.topics-page .stage-head h2{font-size:21px}
.topics-page .stage{gap:18px}
.topics-page .article h3{font-size:17px}
.topics-page .article p{font-size:13px}
}
@media (prefers-reduced-motion:reduce){.topics-page .art-frame img{transition:none}
}
.topics-page .chapter{display:grid;grid-template-columns:205px minmax(0,1fr);gap:40px;padding:46px 0 36px;border-bottom:1px solid var(--line);scroll-margin-top:20px}
.topics-page .chapter-heading{align-self:start;position:sticky;top:25px}
.topics-page .chapter-number{display:block;font-size:68px;line-height:1;color:var(--chapter-ink);font-family:Georgia,"Songti SC",serif;margin-bottom:21px;letter-spacing:-4px}
.topics-page .chapter-count{font-size:11px;color:var(--soft)}
.topics-page .chapter-heading h2{font-size:24px;line-height:1.45;margin:9px 0 13px;letter-spacing:-.5px}
.topics-page .chapter-heading p{font-size:13px;color:var(--soft);line-height:1.9;margin:0;max-width:205px}
.topics-page .reading-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:27px 24px}
.topics-page .reading-card{min-width:0;display:flex;flex-direction:column;border-bottom:1px solid var(--line);padding-bottom:20px}
.topics-page .reading-card[hidden]{display:none}
.topics-page .reading-cover{aspect-ratio:1.96/1;position:relative;background:var(--chapter-tint);border-radius:9px;overflow:hidden}
.topics-page .reading-cover img{width:100%;height:100%;object-fit:contain;display:block;transition:transform .2s ease}
.topics-page .reading-card:hover .reading-cover img{transform:scale(1.025)}
.topics-page .reading-label{position:absolute;bottom:10px;left:10px;background:#f8faf2;color:#344436;padding:4px 9px;font-size:11px;border-radius:4px;box-shadow:0 1px 5px #0001}
.topics-page .cover-fallback{position:absolute;top:8px;right:8px;font-size:10px;color:var(--chapter-ink);background:#f8faf2;padding:3px 6px}
.topics-page .reading-copy{padding:14px 1px 0;display:flex;flex-direction:column;flex:1}
.topics-page .reading-meta{display:flex;justify-content:space-between;font-size:11px;color:var(--soft)}
.topics-page .reading-access{color:var(--chapter-ink)}
.topics-page .reading-copy h3{font-size:17px;line-height:1.65;font-weight:600;margin:8px 0 10px;letter-spacing:-.2px}
.topics-page .reading-copy p{font-size:12px;line-height:1.85;color:var(--soft);margin:0 0 16px;display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}
.topics-page .reading-action{display:flex;justify-content:space-between;font-size:12px;color:var(--chapter-ink);margin-top:auto}
.topics-page .reading-action span{font-size:17px;line-height:1.1}
.topics-page .role-picker{margin-bottom:24px;padding-bottom:16px;border-bottom:1px solid var(--line)}
.topics-page .picker-label{font-size:12px;color:var(--soft)}
.topics-page .role-buttons{display:flex;gap:8px;flex-wrap:wrap;margin-top:10px}
.topics-page .role-buttons button{appearance:none;font:inherit;font-size:12px;color:var(--chapter-ink);background:transparent;border:1px solid #c5cdbb;border-radius:30px;padding:7px 13px;cursor:pointer}
.topics-page .role-buttons button[aria-pressed=true]{background:var(--chapter-ink);color:#f4f7e8;border-color:var(--chapter-ink)}
.topics-page #role-count{font-size:11px;color:var(--soft);margin:13px 0 0}
.topics-page .chapter-main{min-width:0}
@media (max-width:1000px) and (min-width:701px){.topics-page .chapter{grid-template-columns:160px minmax(0,1fr);gap:25px}
.topics-page .chapter-heading h2{font-size:21px}
.topics-page .reading-grid{gap:24px 18px}
.topics-page .reading-copy h3{font-size:16px}
}
@media (max-width:700px){.topics-page .chapter{grid-template-columns:1fr;gap:22px;padding:30px 0}
.topics-page .chapter-heading{position:static;display:flex;gap:20px;align-items:start}
.topics-page .chapter-number{font-size:52px;margin:5px 0 0;letter-spacing:-2px;flex-shrink:0;width:60px}
.topics-page .chapter-heading h2{font-size:23px;margin:4px 0 7px}
.topics-page .chapter-heading p{max-width:none;font-size:13px}
.topics-page .reading-grid{grid-template-columns:1fr;gap:24px}
.topics-page .reading-cover{aspect-ratio:1.96/1}
.topics-page .reading-copy h3{font-size:18px}
.topics-page .reading-copy p{font-size:13px;-webkit-line-clamp:3}
.topics-page .reading-card{padding-bottom:20px}
.topics-page .reading-meta,.topics-page .reading-action{font-size:12px}
.topics-page .role-buttons button{padding:8px 13px}
.topics-page .role-picker{margin-bottom:20px}
.topics-page .path-map{margin-bottom:0}
}
@media (prefers-reduced-motion:reduce){.topics-page .reading-cover img{transition:none}
}

.topics-page{--paper:#f5f2eb;--ink:#262c28;--soft:#59645d;--line:#cdcfc5;--accent:#bb4b32;background:transparent;padding-bottom:35px}.topics-page .chapter{scroll-margin-top:150px}.topics-page .chapter-heading{top:145px}.topics-page .topic-review{font-size:12px;color:var(--soft)}
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