.learn-hero{padding:66px 0 42px;background:linear-gradient(125deg,#f6f3ec,#e4efe7)}.learn-hero h1{font-size:clamp(2.3rem,5vw,4rem);line-height:1.14;margin:8px 0 15px}.learn-hero p{max-width:760px}.learn-count{color:#0f6b63;font-weight:800}.learn-layout{display:grid;grid-template-columns:300px minmax(0,1fr);gap:26px;align-items:start;padding:40px 0 84px}.learn-sidebar,.chapter-detail{background:#fffdf8;border:1px solid #dfe5dd;border-radius:20px;box-shadow:0 12px 30px #10342b0d}.learn-sidebar{padding:18px;position:sticky;top:86px;max-height:calc(100vh - 104px);overflow:auto}.learn-sidebar label{display:block;font-weight:800;font-size:.9rem;margin-bottom:7px}.learn-sidebar input{width:100%;border:1px solid #d3ded6;background:white;border-radius:10px;padding:12px;font-size:1rem}.subject-filters{display:flex;flex-wrap:wrap;gap:6px;margin:15px 0}.subject-filters button{border:1px solid #d3ded6;background:#fff;padding:7px 10px;border-radius:999px;cursor:pointer}.subject-filters button.active{background:#0f6b63;border-color:#0f6b63;color:white}.chapter-list{display:grid;gap:6px}.chapter-list button{text-align:left;border:0;background:transparent;border-radius:10px;padding:9px 10px;cursor:pointer;line-height:1.45;color:#22342e}.chapter-list button:hover,.chapter-list button.active{background:#e7f0eb;color:#0f6b63}.chapter-list small{display:block;color:#66736f;font-size:.76rem}.chapter-detail{padding:clamp(22px,4vw,44px);min-height:560px}.chapter-detail .kicker{color:#e8794e;font-weight:800;font-size:.85rem;letter-spacing:.07em}.chapter-detail h2{font-size:clamp(1.8rem,3.5vw,2.6rem);line-height:1.25;margin:8px 0 20px}.chapter-detail h3{font-size:1.15rem;margin:24px 0 8px}.chapter-detail p{color:#42514b}.chapter-detail ul{padding-left:22px}.chapter-detail li{margin:8px 0}.chapter-box{border-left:4px solid #e8794e;padding:12px 16px;background:#fff4ed;border-radius:0 10px 10px 0;margin-top:22px}.chapter-box strong{color:#7c4735}.chapter-box p{margin:5px 0}.chapter-box.green{border-color:#0f6b63;background:#e9f3ed}.chapter-box.green strong{color:#0f6b63}.chapter-sources{border-top:1px solid #dfe5dd;margin-top:30px;padding-top:15px;font-size:.9rem}.chapter-sources a{color:#0f6b63}.read-button{border:0;background:#0f6b63;color:#fff;border-radius:10px;padding:11px 16px;font-weight:800;cursor:pointer;margin-top:16px}.reading-note{color:#66736f;font-size:.88rem}@media(max-width:760px){.learn-hero{padding:45px 0 25px}.learn-layout{display:block;padding:20px 0 55px}.learn-sidebar{position:static;max-height:none;margin-bottom:18px}.chapter-list{max-height:260px;overflow:auto}.chapter-detail{min-height:0}.subject-filters button{font-size:.82rem}.chapter-detail h2{font-size:1.8rem}}
.chapter-navigation{display:flex;flex-wrap:wrap;gap:9px;margin-top:25px;padding-top:20px;border-top:1px solid #dfe5dd}.chapter-navigation button,.chapter-navigation a{border:1px solid #d3ded6;background:#fff;color:#0f6b63;border-radius:10px;padding:9px 13px;font:inherit;font-weight:700;text-decoration:none;cursor:pointer}
.learn-roadmap{padding-bottom:72px}.learn-roadmap h2{font-size:clamp(1.8rem,3vw,2.5rem);margin:4px 0 22px}.roadmap-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}.roadmap-grid article{background:#fffdf8;border:1px solid #dfe5dd;border-radius:18px;padding:22px}.roadmap-grid span{font-weight:900;color:#e8794e}.roadmap-grid h3{margin:10px 0 6px}.roadmap-grid p{margin:0;color:#66736f}@media(max-width:760px){.roadmap-grid{grid-template-columns:1fr}.learn-roadmap{padding-bottom:48px}}
.deep-sections{margin:28px 0;padding:22px 24px;border:1px solid #dce8df;background:#f7faf6;border-radius:16px}.deep-sections h3{margin:0 0 14px}.deep-section+.deep-section{margin-top:18px;padding-top:16px;border-top:1px solid #dce8df}.deep-section h4{margin:0 0 6px;color:#145e58;font-size:1.05rem}.deep-section p{margin:0;line-height:1.82}.worked-example{background:#edf4fb;border-left-color:#4180a1}.worked-example strong{color:#225d7b}.worked-example p{line-height:1.7}@media(max-width:760px){.deep-sections{padding:18px}}