:root{--paper:#f7f8f5;--ink:#20352e;--muted:#7b8780;--green:#176954;--line:#e2e7df;--font:"PingFang SC","Microsoft YaHei",system-ui,sans-serif}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:100px}body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--font);-webkit-font-smoothing:antialiased}button,input,a{-webkit-tap-highlight-color:transparent}button,input{font:inherit}button,a{touch-action:manipulation}a{color:inherit;text-decoration:none}button{cursor:pointer}button:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid #79b7a1;outline-offset:5px}button{color:inherit}button:disabled{cursor:default}button, input{border-radius:0}[hidden]{display:none!important}.skip-link{position:fixed;top:-80px;left:20px;z-index:100;background:#fff;padding:14px}.skip-link:focus{top:12px}
.site-header{height:94px;max-width:1360px;margin:auto;display:flex;align-items:center;gap:68px;padding:0 44px;border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:11px}.brand-mark{display:grid;place-items:center;background:var(--green);border-radius:12px;width:43px;height:43px;color:#fff;font-size:29px;font-weight:500;line-height:1}.brand strong{font-size:21px;font-weight:650;letter-spacing:2px;display:block}.brand strong span{display:block;font-size:8px;letter-spacing:1.7px;font-weight:500;margin-top:4px;color:#78867d}.site-header nav{display:flex;gap:32px;align-self:stretch;align-items:center;font-size:14px}.site-header nav>a,.site-header nav>button{position:relative;height:100%;display:flex;align-items:center;gap:7px;background:none;border:0;padding:0;white-space:nowrap;color:#738078}.site-header nav .active{color:var(--green);font-weight:600}.site-header nav .active:after{position:absolute;content:"";height:3px;bottom:-1px;left:0;right:0;background:var(--green);border-radius:3px}.site-header nav span{font-size:11px;background:#e8ede7;padding:2px 5px;border-radius:4px}.header-note{margin-left:auto;font-size:12px;color:#7e8a82;white-space:nowrap;display:flex;gap:8px;align-items:center}.header-note i{width:6px;height:6px;background:#75a88c;border-radius:50%}main{max-width:1360px;margin:auto;padding:0 44px}.hero{display:grid;grid-template-columns:.92fr 1.08fr;gap:40px;align-items:center;padding:50px 0 58px}.eyebrow{font-size:10px;font-weight:600;letter-spacing:2.3px;color:#6b8375;display:flex;align-items:center;gap:8px}.eyebrow>span{width:20px;height:1px;background:var(--green)}h1{font-size:clamp(36px,3.8vw,53px);line-height:1.45;letter-spacing:1px;font-weight:620;margin:20px 0 13px}h1 em{font-style:normal;color:var(--green)}.hero-copy>p{font-size:15px;color:#7a877e;letter-spacing:.7px;margin:0 0 29px}.primary-link{display:inline-flex;align-items:center;gap:41px;background:var(--green);color:white;border:1px solid var(--green);border-radius:7px;padding:12px 18px;font-size:14px;transition:background .2s,transform .2s}.primary-link:hover{background:#10503e;transform:translateY(-2px)}.primary-link span{font-size:19px}.hero-meta{display:flex;align-items:center;gap:15px;font-size:10px;color:#8b958c;margin-top:27px;white-space:nowrap}.hero-meta b{font-size:15px;color:#52695b;font-weight:600}.hero-meta i{width:1px;height:11px;background:#dce3d9}.hero-visual{position:relative;min-width:0;display:block;aspect-ratio:1.55;overflow:hidden;border-radius:18px;background:#dbe9e6}.hero-visual>img{height:100%;width:100%;object-fit:cover;transition:transform .7s}.hero-visual:hover>img{transform:scale(1.04)}.hero-visual:after{content:"";position:absolute;inset:45% 0 0;background:linear-gradient(transparent,rgba(19,51,48,.76))}.visual-label{position:absolute;left:24px;top:21px;background:#ffffffc9;backdrop-filter:blur(8px);border:1px solid #ffffffc9;border-radius:20px;padding:8px 12px;display:flex;align-items:center;gap:6px;font-size:10px;color:#375d52}.visual-label i{width:5px;height:5px;border-radius:50%;background:var(--green)}.visual-caption{position:absolute;left:25px;bottom:25px;right:25px;color:#fff;z-index:1;display:flex;align-items:center;justify-content:space-between}.visual-caption small{font-size:10px;letter-spacing:1px;opacity:.8}.visual-caption strong{display:block;font-size:22px;font-weight:500;margin-top:7px}.circle-arrow{width:40px;height:40px;border-radius:50%;border:1px solid #ffffff66;background:#ffffff19;display:grid;place-items:center;font-size:23px}.course-section{padding:0 0 50px}.section-top{display:flex;align-items:flex-end;justify-content:space-between;gap:22px}.section-top .eyebrow{font-size:9px;letter-spacing:2px}h2{font-size:25px;font-weight:600;letter-spacing:.5px;margin:8px 0 0}h2>span{margin-left:15px;font-size:11px;letter-spacing:0;font-weight:400;color:#879187}.search-box{display:flex;align-items:center;gap:9px;min-width:260px;padding:11px 13px;border:1px solid #dfe5dd;border-radius:7px;background:#ffffff80}.search-box svg{width:17px;height:17px;color:#7e8a81}.search-box input{width:100%;background:none;border:0;outline:none;color:var(--ink);font-size:12px}.search-box input::placeholder{color:#929b92}.search-box:focus-within{border-color:#5f9a7b;box-shadow:0 0 0 3px #1769540b}.search-box kbd{font-size:10px;line-height:16px;width:16px;text-align:center;color:#a0a79f;border:1px solid #dfe5dd;border-radius:3px}.filter-row{display:flex;justify-content:space-between;align-items:center;gap:12px;margin:25px 0 24px;padding-bottom:17px;border-bottom:1px solid var(--line)}.subject-tabs{display:flex;gap:8px}.subject-tabs button{display:flex;align-items:center;gap:7px;white-space:nowrap;padding:9px 15px;border-radius:6px;background:none;border:1px solid transparent;font-size:12px;color:#78867c}.subject-tabs button span{font-size:9px;opacity:.7}.subject-tabs button[aria-pressed="true"]{background:#e8eee5;color:var(--green);font-weight:600}.subject-tabs button:hover{background:#edf1e9}.favorites-filter{background:none;border:0;font-size:11px;white-space:nowrap;display:flex;align-items:center;gap:6px;color:#7d8b80}.favorites-filter>span{font-size:18px}.favorites-filter[aria-pressed="true"]{color:var(--green)}.course-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:26px 22px}.course-card{position:relative;border:1px solid #e5e9e0;border-radius:11px;background:#fff;overflow:hidden;transition:transform .22s,box-shadow .22s}.course-card:hover{transform:translateY(-4px);box-shadow:0 12px 28px #243c2910}.card-image{display:block;aspect-ratio:16/9;position:relative;background:#edf2f1;overflow:hidden}.card-image img{width:100%;height:100%;object-fit:cover;display:block;transition:transform .4s}.course-card:hover .card-image img{transform:scale(1.045)}.card-subject{position:absolute;left:12px;top:12px;padding:4px 8px;border:1px solid #ffffffb0;border-radius:4px;background:#ffffffdf;font-size:10px;color:#5a7265;backdrop-filter:blur(8px)}.card-favorite{position:absolute;right:10px;top:10px;display:grid;place-items:center;border:1px solid #ffffffbb;border-radius:50%;width:28px;height:28px;background:#ffffffc9;color:#60746a;font-size:17px;z-index:2}.card-favorite[aria-pressed="true"]{color:#176954;background:#e9f4eb}.card-body{padding:16px 16px 13px}.card-body h3{font-size:15px;font-weight:600;letter-spacing:.1px;margin:0 0 8px;line-height:1.5}.card-tags{font-size:10px;color:#94a095;line-height:1.7;margin:0;min-height:18px}.card-bottom{margin-top:15px;padding-top:11px;border-top:1px solid #f0f2ec;display:flex;justify-content:space-between;align-items:center;color:#8e998e;font-size:9px}.card-bottom .enter{display:flex;align-items:center;gap:5px;font-size:10px;font-weight:500;color:#537963}.card-bottom .enter b{font-size:15px;font-weight:400}.progress-mark{position:absolute;left:0;bottom:0;height:2px;background:#87b69a}.continue-card{border:1px solid #d8e5d6;background:#edf3e9;padding:15px 18px;margin:0 0 24px;border-radius:8px;display:flex;align-items:center;gap:12px}.continue-card .continue-dot{display:grid;place-items:center;width:32px;height:32px;border-radius:50%;background:#dfeada;color:var(--green)}.continue-card p{margin:0;font-size:12px;font-weight:500}.continue-card small{font-size:10px;color:#80917e}.continue-card a{margin-left:auto;color:var(--green);font-size:12px}.continue-card button{background:none;border:0;color:#80917e;font-size:18px;padding:4px}.results-status{text-align:center;font-size:10px;color:#9aa494;margin:27px 0 0;letter-spacing:1px}.empty-state{text-align:center;padding:55px 20px;background:#eff3ec;border-radius:10px}.empty-state>span{font-size:40px;color:#789580}.empty-state h3{font-size:17px;font-weight:500}.empty-state p{font-size:12px;color:#879282}.empty-state button{margin-top:12px;border:1px solid #b9ccb7;background:#fff;color:var(--green);font-size:12px;padding:9px 15px;border-radius:6px}.site-footer{max-width:1272px;margin:0 auto;display:flex;align-items:center;justify-content:space-between;gap:20px;padding:25px 0 33px;border-top:1px solid var(--line);font-size:10px;color:#8d988d}.footer-brand{font-size:13px;color:#48654f;font-weight:600}.footer-brand span{font-size:10px;font-weight:400;margin-left:18px;color:#8d988d}.site-toast{position:fixed;bottom:25px;left:50%;transform:translate(-50%,20px);background:#203e32;color:#fff;padding:12px 20px;border-radius:8px;font-size:12px;z-index:100;opacity:0;pointer-events:none;transition:.2s}.site-toast.on{opacity:1;transform:translate(-50%,0)}.noscript{padding:20px;text-align:center}
@media(min-width:1500px){.hero{padding-top:64px;padding-bottom:64px}.hero-visual{aspect-ratio:1.58}}
@media(max-width:1100px){.site-header{padding:0 30px;gap:40px}main{padding:0 30px}.hero{gap:25px}h1{font-size:36px}.hero-meta{gap:10px;font-size:9px}.hero-meta span:last-child{display:none}.hero-visual{aspect-ratio:1.2}.course-grid{grid-template-columns:repeat(3,minmax(0,1fr))}.site-footer{margin:0 30px}.header-note{display:none}}
@media(max-width:760px){.site-header{height:76px;padding:0 24px;gap:20px;justify-content:space-between}.site-header nav{gap:20px;font-size:12px}.brand strong{font-size:18px}.brand-mark{height:36px;width:36px;font-size:24px}.brand strong span{font-size:7px}.site-header nav span{display:none}main{padding:0 24px}.hero{gap:20px;padding:33px 0 39px}.hero-copy .eyebrow{font-size:8px;letter-spacing:1px}h1{font-size:29px;line-height:1.5;letter-spacing:0;margin-top:15px}.hero-copy>p{font-size:11px;letter-spacing:0;line-height:1.8;margin-bottom:20px}.primary-link{font-size:11px;padding:9px 13px;gap:20px}.hero-meta{margin-top:19px}.hero-visual{aspect-ratio:.95;border-radius:12px}.visual-label{left:12px;top:12px;font-size:8px;padding:6px 8px}.visual-caption{left:15px;right:15px;bottom:17px}.visual-caption small{font-size:8px}.visual-caption strong{font-size:15px;line-height:1.5}.circle-arrow{width:29px;height:29px;font-size:17px;flex-shrink:0}.section-top{align-items:center}h2{font-size:20px}h2>span{display:block;font-size:10px;margin:7px 0 0}.search-box{min-width:0;width:200px;font-size:10px;padding:10px}.search-box input{font-size:10px}.course-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:18px 15px}.subject-tabs{gap:3px}.subject-tabs button{padding:8px 10px;font-size:11px;gap:4px}.filter-row{margin:20px 0}.favorites-filter{font-size:10px}.card-body h3{font-size:14px}.card-body{padding:14px}.card-tags{font-size:9px}.card-subject{font-size:9px;left:10px;top:10px}.site-footer{margin:0 24px}.site-footer>span{display:none}}
@media(max-width:480px){.site-header{padding:0 18px;gap:10px;height:72px}.site-header nav{gap:14px;font-size:11px}.brand strong{font-size:17px;letter-spacing:1px}.brand{gap:8px}.brand-mark{width:33px;height:33px}.brand strong span{font-size:6px;letter-spacing:1.1px}main{padding:0 18px}.hero{display:flex;flex-direction:column;align-items:stretch;padding-top:30px;gap:25px}.hero-copy{position:relative}h1{font-size:34px;line-height:1.4}.hero-copy>p{font-size:12px;margin-bottom:0}.primary-link{position:absolute;bottom:0;right:0;font-size:11px;gap:18px}.hero-meta{margin-top:23px}.hero-visual{aspect-ratio:1.8}.visual-label{top:14px;left:16px}.visual-caption strong{font-size:18px}.section-top{flex-wrap:wrap;gap:17px}h2>span{display:inline;margin-left:9px}.search-box{width:100%;padding:11px 12px}.section-top .eyebrow{font-size:8px}.subject-tabs{gap:0;justify-content:space-between;flex:1}.subject-tabs button{padding:8px 7px;font-size:11px}.subject-tabs button span{font-size:8px}.filter-row{align-items:center;gap:4px;padding-bottom:13px;margin:16px 0 20px}.favorites-filter{font-size:0;padding:5px}.favorites-filter>span{font-size:20px}.course-grid{gap:15px 11px}.card-body{padding:11px 10px}.card-body h3{font-size:12px;margin-bottom:6px}.card-tags{font-size:8px;min-height:28px}.card-bottom{margin-top:9px;padding-top:9px;font-size:8px}.card-bottom .enter{font-size:9px}.card-favorite{width:25px;height:25px;font-size:15px;top:8px;right:8px}.card-subject{font-size:8px;padding:3px 6px;top:8px;left:8px}.footer-brand span{display:block;margin:5px 0 0}.site-footer{margin:0 18px;padding-bottom:23px}.continue-card{padding:12px 10px;gap:8px}.continue-card p{font-size:10px}.continue-card a{font-size:10px;white-space:nowrap}.continue-card .continue-dot{width:26px;height:26px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition:none!important;animation:none!important}}
/* Resource recovery leaves the course link and its label usable. */
.hero{position:relative}.card-image.media-failed img,.hero-visual.media-failed img{object-fit:cover}.image-retry{position:absolute;z-index:4;left:50%;top:76px;transform:translateX(-50%);max-width:90%;border:1px solid #bcd0c0;border-radius:6px;background:#fffffff2;color:#3f6e52;padding:8px 12px;font:11px var(--font);white-space:nowrap;cursor:pointer}.hero>.image-retry{left:auto;right:12%;top:46%;transform:none}.card-image.media-failed .card-subject{opacity:.8}