:root{font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif;color:#1d1d1f;background:#f5f5f7;font-size:16px;line-height:1.65;--accent:#0066cc;--line:#dedee3;--muted:#626269}
*{box-sizing:border-box}body{margin:0}button,input,select,textarea{font:inherit}a{color:var(--accent)}button,a,input,select,textarea{touch-action:manipulation;-webkit-tap-highlight-color:transparent}button:focus-visible,a:focus-visible{outline:3px solid #0071e3;outline-offset:4px}header{position:sticky;top:0;z-index:20;background:rgba(255,255,255,.88);backdrop-filter:blur(22px);-webkit-backdrop-filter:blur(22px);border-bottom:1px solid rgba(0,0,0,.07);padding:15px max(24px,calc((100vw - 1180px)/2));display:flex;align-items:center;justify-content:space-between;gap:20px}.brand{display:flex;align-items:center;gap:12px;font-size:15px;font-weight:600;line-height:1.45;text-decoration:none;color:#1d1d1f}.brand small{display:block;font-size:12px;font-weight:400;color:var(--muted);letter-spacing:2px;margin-top:2px}.mark{width:34px;height:34px;display:grid;place-items:center;border:1px solid #d2d3d7;border-radius:50%;color:var(--accent);font-size:26px;font-weight:300;flex-shrink:0}.header-note{font-size:13px;color:var(--muted);white-space:nowrap}main{max-width:1180px;margin:auto;padding:42px 24px 80px}h1,h2,h3,p{margin-top:0}h1{font-size:44px;line-height:1.2;letter-spacing:-1.5px;margin-bottom:18px;font-weight:650}h2{font-size:27px;line-height:1.35;letter-spacing:-.5px;margin-bottom:16px}h3{font-size:21px;line-height:1.5;font-weight:600;margin-bottom:0}p{margin-bottom:16px}.muted{color:var(--muted)}.eyebrow{font-size:14px;letter-spacing:2px;font-weight:550;color:var(--muted);display:block;margin-bottom:12px}
.welcome{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(0,.9fr);gap:56px;align-items:center;min-height:calc(100vh - 185px)}.intro{min-width:0}.intro h1{font-size:clamp(38px,4.5vw,59px);line-height:1.22;letter-spacing:-2px;margin-bottom:22px}.intro h1 span{color:#717177}.intro>p{max-width:370px;font-size:17px;line-height:1.8}.intro-art{display:block;width:100%;height:auto;aspect-ratio:1.9;object-fit:cover;object-position:70% 65%;border-radius:22px;margin:30px 0 20px;mix-blend-mode:multiply}.intro-caption{font-size:13px;color:var(--muted);display:flex;gap:18px;flex-wrap:wrap}.intro-caption span+span:before{content:'·';margin-right:18px}.panel{background:white;border:1px solid rgba(0,0,0,.055);border-radius:24px;padding:30px}.welcome .panel{padding:32px 34px;box-shadow:0 12px 50px rgba(0,0,0,.035)}.form-subtitle{font-size:14px;color:var(--muted);margin-top:-5px;margin-bottom:24px}.field{display:block;font-size:14px;font-weight:550;margin:0 0 18px}.field input,.field select,.field textarea{margin-top:7px}input,select,textarea{width:100%;min-height:50px;padding:12px 14px;border:1px solid #c4c5ca;border-radius:12px;background:white;color:#1d1d1f;font-size:16px;line-height:1.5;transition:border-color .18s,box-shadow .18s}input::placeholder,textarea::placeholder{color:#76767c;font-weight:400}input:disabled,select:disabled{background:#f5f5f7;color:#85858c;opacity:1}input:focus,select:focus,textarea:focus{outline:none;border-color:#0071e3;box-shadow:0 0 0 3px rgba(0,113,227,.16)}textarea{min-height:150px;resize:vertical}input[aria-invalid=true]{border-color:#ba2929}.field-note,.field-error{display:block;font-size:13px;color:var(--muted);margin-top:6px;font-weight:400}.field-error{color:#ba2929}.field-error:empty{display:none}#school-search{min-height:42px;font-size:14px;background:#f5f5f7;border-color:transparent;padding:9px 13px}#school-search:focus{background:white}.form-pair{display:grid;grid-template-columns:1fr 1fr;gap:14px}
button,.button{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:46px;padding:11px 22px;border:1px solid transparent;border-radius:999px;background:#0071e3;color:white;font-size:15px;line-height:1.5;text-decoration:none;cursor:pointer;font-weight:500;transition:background .18s,transform .18s,box-shadow .18s}button:hover,.button:hover{background:#0077ed}button:active,.button:active{transform:scale(.98)}button:disabled{opacity:.55;cursor:wait}.secondary{background:#eaeaec;color:#1d1d1f}.secondary:hover{background:#dedee2}.wide{width:100%;min-height:50px}.text-button{background:transparent;color:var(--accent);padding:8px 12px;min-height:42px;white-space:nowrap}.text-button:hover{background:rgba(0,102,204,.06)}.hint{font-size:13px;color:var(--muted);line-height:1.65;margin:16px 0 0}.error{color:#ba2929;font-size:14px;margin:12px 0}.topline,.row{display:flex;align-items:center;justify-content:space-between;gap:18px}.topline{margin-bottom:28px}.topline h1{margin-bottom:9px}.identity{font-size:13px;color:var(--muted);text-align:right;max-width:45%}.identity .text-button{margin-top:4px}
.collection-banner{position:relative;min-height:220px;background:#eaf0f6;border-radius:28px;overflow:hidden;margin-bottom:36px;display:flex;align-items:center}.collection-banner img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;object-position:70% 60%}.banner-copy{position:relative;padding:32px 38px;max-width:48%;z-index:1}.banner-copy h2{font-size:31px;line-height:1.3;letter-spacing:-1px;margin-bottom:10px}.banner-copy p{font-size:14px;color:#535c68;margin:0}.section-heading{display:flex;align-items:baseline;justify-content:space-between;gap:12px;margin-bottom:18px}.section-heading h2{margin:0}.section-heading span{font-size:14px;color:var(--muted)}.grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.course{position:relative;display:flex;flex-direction:column;min-height:218px;border:1px solid rgba(0,0,0,.045);background:white;border-radius:24px;padding:26px 28px;text-decoration:none;color:inherit;transition:transform .25s cubic-bezier(.2,.7,.2,1),box-shadow .25s,border-color .25s}.course-top{display:flex;align-items:center;justify-content:space-between;margin-bottom:20px}.number{font-size:13px;letter-spacing:1.5px;color:var(--muted);font-weight:500}.course-type{font-size:12px;padding:3px 9px;border-radius:6px;background:#f5f5f7;color:var(--muted)}.course h3{max-width:95%;flex:1}.course-bottom{display:flex;align-items:center;justify-content:space-between;gap:16px;margin-top:22px}.meta{font-size:14px;color:var(--muted)}.play-link{display:flex;align-items:center;gap:10px;color:var(--accent);font-size:14px;white-space:nowrap}.play-glyph{display:grid;place-items:center;width:30px;height:30px;background:#f1f6fc;border-radius:50%;font-size:11px;padding-left:2px;transition:background .2s,color .2s}.course:hover{transform:translateY(-4px);box-shadow:0 14px 35px rgba(29,29,31,.075)}.course:hover .play-glyph{background:#0071e3;color:white}
.section{margin-top:40px}.resources{background:white;border:1px solid rgba(0,0,0,.05);border-radius:24px;padding:4px 26px}.resource{display:flex;align-items:center;justify-content:space-between;gap:24px;padding:20px 0;border-bottom:1px solid #eeeef0;font-size:15px}.resource:last-child{border:0}.resource a{white-space:nowrap;text-decoration:none;font-size:14px;padding:6px 0}.resource a:hover{text-decoration:underline}.resource-file{display:flex;align-items:center;gap:16px}.file-badge{font-size:10px;font-weight:650;letter-spacing:.7px;padding:9px 6px;color:#65656c;background:#f5f5f7;border:1px solid #e4e4e8;border-radius:5px;flex-shrink:0}.back{display:inline-flex;align-items:center;min-height:44px;color:var(--accent);font-size:14px;text-decoration:none}.back:hover{text-decoration:underline}.player-heading{margin:24px 0}.player-heading h1{font-size:34px;line-height:1.4;max-width:900px;margin-bottom:10px}.player-heading p{font-size:14px;color:var(--muted);margin:0}.player{width:100%;max-height:70vh;background:#101014;border-radius:20px;display:block;box-shadow:0 18px 45px rgba(0,0,0,.1)}.video-actions{display:flex;justify-content:flex-end;align-items:center;gap:12px;margin-top:18px;font-size:14px}.video-actions select{width:auto;min-height:40px;padding:6px 12px;border-radius:10px;font-size:14px}.description{white-space:pre-wrap;line-height:1.95;margin-bottom:0;color:#45454b}.course-pagination{display:flex;justify-content:space-between;gap:20px;border-top:1px solid var(--line);margin-top:36px;padding-top:22px}.course-pagination a{font-size:14px;text-decoration:none;max-width:46%;line-height:1.6}.course-pagination a:last-child{text-align:right;margin-left:auto}.course-pagination small{display:block;color:var(--muted);font-size:12px;margin-bottom:5px}
.tabs{display:inline-flex;background:#e8e8ed;padding:4px;border-radius:999px;gap:4px;margin:24px 0}.tabs button{background:none;color:#55555b;padding:8px 25px;min-height:40px}.tabs button.active{background:white;color:#1d1d1f;box-shadow:0 2px 7px rgba(0,0,0,.08)}.table-wrap{overflow:auto;background:white;border:1px solid #e5e5e9;border-radius:18px}table{border-collapse:collapse;width:100%;font-size:14px;text-align:left;white-space:nowrap}td,th{padding:16px 20px;border-bottom:1px solid #eeeef0}th{background:#fafafa;font-size:12px;font-weight:600;color:var(--muted)}tbody tr:last-child td{border-bottom:0}tbody tr:hover{background:#fafbfd}.toolbar{display:flex;gap:12px;align-items:center;flex-wrap:wrap;margin:22px 0}.toolbar input{max-width:320px;background:white}.toolbar #export{margin-left:auto}.editor-grid{display:grid;grid-template-columns:290px minmax(0,1fr);gap:26px}.course-menu{display:flex;flex-direction:column;gap:6px;align-self:start;position:sticky;top:100px}.course-menu button{text-align:left;justify-content:flex-start;background:transparent;color:#55555b;border:1px solid transparent;font-size:14px;border-radius:12px;padding:12px 16px}.course-menu button.active{background:white;color:#0066cc;box-shadow:0 2px 10px rgba(0,0,0,.035)}.course-menu #add-course{background:#e6effa;color:#0066cc;margin-bottom:10px;justify-content:center}.check{display:flex;gap:10px;align-items:center;font-size:14px}.check input{width:19px;min-height:19px;accent-color:#0071e3}.login{max-width:430px;margin:9vh auto;padding:36px}.login h1{font-size:32px}.empty{padding:40px;text-align:center;color:var(--muted)}#toast{position:fixed;bottom:24px;left:50%;transform:translateX(-50%);max-width:calc(100vw - 32px);background:rgba(29,29,31,.94);color:white;padding:13px 24px;border-radius:14px;box-shadow:0 6px 24px rgba(0,0,0,.16);display:none;z-index:40;font-size:14px}.view-enter{animation:view-enter .3s ease-out}@keyframes view-enter{from{opacity:.35;transform:translateY(7px)}to{opacity:1;transform:translateY(0)}}.skip-link{position:fixed;top:-100px;left:16px;z-index:50;background:white;padding:10px}.skip-link:focus{top:10px}.site-footer{max-width:1132px;margin:0 auto;padding:20px 0 30px;border-top:1px solid var(--line);color:var(--muted);font-size:12px;display:flex;justify-content:space-between;gap:16px}
@media(max-width:900px){.welcome{gap:28px}.intro h1{font-size:40px}.welcome .panel{padding:28px}.form-pair{grid-template-columns:1fr;gap:0}.banner-copy{max-width:52%}.editor-grid{grid-template-columns:240px minmax(0,1fr)}}
@media(max-width:650px){header{padding:12px 18px}.brand{font-size:12px;gap:9px}.brand small{font-size:11px;letter-spacing:1px}.mark{width:29px;height:29px;font-size:23px}.header-note{display:none}main{padding:28px 18px 48px}.welcome{display:flex;flex-direction:column;gap:24px;align-items:stretch;min-height:0}.intro{padding:0 4px}.intro h1{font-size:36px;line-height:1.2;letter-spacing:-1.2px;margin-bottom:12px}.intro .eyebrow{font-size:12px;margin-bottom:10px}.intro>p{font-size:14px;max-width:100%;margin-bottom:0}.intro-art,.intro-caption{display:none}.welcome .panel{padding:25px 22px;border-radius:22px}.panel{padding:24px}.form-subtitle{margin-bottom:20px}.form-pair{grid-template-columns:1fr 1fr;gap:12px}.field{font-size:14px;margin-bottom:17px}.topline{align-items:flex-start;gap:16px;margin-bottom:24px}.topline h1{font-size:33px;letter-spacing:-1px}.topline .muted{font-size:13px}.identity{font-size:12px;max-width:46%;padding-top:7px}.eyebrow{font-size:12px}.collection-banner{min-height:175px;margin-bottom:28px;border-radius:22px}.collection-banner img{object-position:75% 60%}.banner-copy{max-width:54%;padding:24px 20px;background:linear-gradient(90deg,rgba(242,246,251,.9),rgba(242,246,251,0))}.banner-copy h2{font-size:25px;letter-spacing:-.5px}.banner-copy p{font-size:12px;max-width:120px}.grid{grid-template-columns:1fr;gap:14px}.course{padding:23px;min-height:185px;border-radius:22px}.course-top{margin-bottom:13px}.course h3{font-size:20px;max-width:100%}.course-bottom{margin-top:17px}.section-heading h2,h2{font-size:24px}.section{margin-top:32px}.resources{padding:0 20px}.resource{font-size:14px;gap:14px;padding:19px 0;align-items:flex-start}.resource-file{gap:12px}.resource a{font-size:13px;min-height:40px;display:flex;align-items:center;padding:0}.file-badge{margin-top:2px}.player-heading{margin:18px 0}.player-heading h1{font-size:27px;line-height:1.4;letter-spacing:-.7px}.player{border-radius:14px}.row{flex-wrap:wrap}.course-pagination a{font-size:13px}.editor-grid{display:block}.course-menu{position:static;max-height:260px;overflow:auto;margin-bottom:24px;border-bottom:1px solid var(--line);padding-bottom:12px}.toolbar{gap:9px}.toolbar input{max-width:100%;flex:1 1 200px}.toolbar #export{margin-left:0}.toolbar .button{width:100%}.tabs{display:flex;width:100%}.tabs button{flex:1}.site-footer{margin:0 18px;display:block;font-size:11px;padding:18px 0}.site-footer span{display:block;margin-bottom:4px}.login{margin:5vh auto}.course:hover{transform:none}}
@media(max-width:360px){.form-pair{grid-template-columns:1fr;gap:0}.intro h1{font-size:31px}.identity{max-width:42%}.banner-copy h2{font-size:22px}.play-link{font-size:13px}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}
.intro-art{aspect-ratio:3/2;object-fit:contain;mix-blend-mode:normal;max-height:330px;background:#f4f5f6}
.collection-banner{aspect-ratio:3/1;min-height:230px;background:#f5f5f7}
.collection-banner img{object-fit:contain;object-position:center}
.banner-copy{max-width:48%;background:none}
.resources-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:24px;align-items:start}
.resource-art{margin:0;border-radius:24px;overflow:hidden;background:#f5f5f7;position:sticky;top:100px}
.resource-art img{display:block;width:100%;height:auto;object-fit:contain}
@media(max-width:900px){.resources-layout{grid-template-columns:minmax(0,1fr) 230px}.banner-copy h2{font-size:27px}}
@media(max-width:650px){.collection-banner{aspect-ratio:auto;min-height:0;flex-direction:column;align-items:stretch;background:#f4f5f6}.collection-banner img{position:relative;inset:auto;width:100%;height:auto;order:2}.banner-copy{max-width:100%;padding:24px 24px 0;background:none}.banner-copy h2{font-size:27px;margin:0}.resources-layout{display:flex;flex-direction:column;gap:18px}.resources-layout .resources{width:100%;order:2}.resource-art{position:static;width:100%;max-width:300px;align-self:center;margin:0}.resource-art img{max-height:170px}}
.school-picker{position:relative}.school-toggle{display:flex;justify-content:space-between;align-items:center;width:100%;border:1px solid #c7c7cc;border-radius:14px;background:white;color:#1d1d1f;text-align:left;padding:15px 16px;font:inherit}.school-toggle:disabled{background:#f5f5f7;color:#86868b}.school-popup{margin-top:8px;padding:10px;border:1px solid #d2d2d7;border-radius:16px;background:#fff;box-shadow:0 12px 30px #00000010}.school-popup[hidden]{display:none}.school-popup input{width:100%;margin-bottom:8px}.school-option{display:block;width:100%;background:#fff;color:#1d1d1f;text-align:left;border-radius:10px;padding:12px;font:inherit}.school-option:hover,.school-option:focus{background:#eef5ff}.school-option small{display:block;color:#6e6e73;font-size:12px;margin-top:4px}#school-options{max-height:230px;overflow:auto}.delete-person{color:#b42318;background:#fff1f0;border:1px solid #f5ceca;border-radius:9px;padding:8px 12px;white-space:nowrap}
.welcome{min-height:calc(100vh - 122px);gap:64px;align-items:center}.intro .training-title{font-size:clamp(34px,3.7vw,52px);line-height:1.22;letter-spacing:-1.3px;margin-bottom:26px;white-space:nowrap}.training-summary{font-size:19px;line-height:1.75;color:#626269;max-width:530px;margin:0}.intro .intro-art{margin:38px 0 0;aspect-ratio:1.9;max-height:310px;object-fit:cover;object-position:70% 55%;background:transparent}.topline{justify-content:flex-end}.banner-copy .training-title{font-size:clamp(26px,3vw,38px);line-height:1.45;letter-spacing:-.6px;margin:0}@media(max-width:900px){.welcome{gap:32px}.intro .training-title{font-size:clamp(30px,3.6vw,42px);white-space:normal}.training-summary{font-size:17px}}@media(max-width:650px){.welcome{gap:28px;min-height:0}.intro .training-title{font-size:clamp(29px,8vw,37px);line-height:1.28;margin-bottom:16px;letter-spacing:-.8px}.training-summary{font-size:16px;line-height:1.7}.intro .intro-art{display:block;margin:22px 0 0;aspect-ratio:2.35;max-height:165px;border-radius:18px}.banner-copy .training-title{font-size:27px}}@media(max-width:380px){.intro .training-title{font-size:27px}}
.training-rationale{display:grid;grid-template-columns:minmax(0,.9fr) minmax(0,1.1fr);gap:82px;margin:42px 0 20px;padding:72px 76px;background:#fff;border:1px solid rgba(0,0,0,.045);border-radius:32px}.rationale-kicker{display:block;margin-bottom:26px;font-size:13px;letter-spacing:.18em;font-weight:650;color:#0066cc}.rationale-lead h2{font-size:clamp(30px,3.3vw,43px);line-height:1.3;letter-spacing:-1.1px;margin-bottom:25px}.rationale-lead p{font-size:17px;line-height:1.9;color:#5d5d64;max-width:425px;margin:0}.rationale-argument{border-top:1px solid #e6e6e9}.rationale-item{padding:23px 0 24px;border-bottom:1px solid #e6e6e9}.rationale-index{display:block;font-size:12px;font-weight:650;letter-spacing:.08em;color:#6e6e73;margin-bottom:9px}.rationale-item h3{font-size:20px;line-height:1.45;letter-spacing:-.25px;margin-bottom:8px}.rationale-item p{font-size:15px;line-height:1.85;color:#616168;margin:0}@media(max-width:900px){.training-rationale{gap:40px;padding:50px 42px}}@media(max-width:650px){.training-rationale{display:block;margin:44px 0 0;padding:35px 26px;border-radius:25px}.rationale-kicker{margin-bottom:17px}.rationale-lead h2{font-size:29px;margin-bottom:15px}.rationale-lead p{font-size:15px;line-height:1.85;margin-bottom:28px}.rationale-item h3{font-size:19px}}

/* September content revision: readable long-form introduction. */
.welcome{grid-template-columns:minmax(0,1.15fr) minmax(0,.85fr);gap:48px;align-items:start;min-height:0;padding:24px 0 12px}.intro .training-title{font-size:clamp(28px,3vw,39px);line-height:1.4;white-space:normal;letter-spacing:-.8px;margin-bottom:16px}.training-subtitle{font-size:23px;line-height:1.5;color:#0066cc;margin-bottom:23px}.intro .training-summary{font-size:16px;line-height:1.95;max-width:none;color:#616168}.intro .intro-art{height:240px;object-fit:cover;object-position:center 36%;margin-top:26px;aspect-ratio:auto}.registration-notice{font-size:12px;color:#6e6e73;line-height:1.75;margin:18px 0 0}.training-rationale{gap:52px;padding:50px;margin-top:48px;grid-template-columns:1fr 1fr}.rationale-lead h2{font-size:28px;line-height:1.5;letter-spacing:-.5px}.rationale-lead p{font-size:15px;line-height:1.95;margin-bottom:18px}.rationale-argument{border-top:0}.rationale-argument>h2{font-size:26px;line-height:1.5;margin-bottom:10px}.rationale-item{padding:18px 0}.rationale-item h3{font-size:18px}.source-links{display:flex;flex-wrap:wrap;gap:16px;font-size:12px;margin-top:24px}.source-links a{text-decoration:none}.collection-banner{aspect-ratio:auto;min-height:300px;background:#eaf0ee}.collection-banner img{inset:0 0 0 auto;width:48%;object-fit:cover}.banner-copy{max-width:52%;padding:36px}.banner-copy .project-label{font-size:16px;line-height:1.8;color:#53625e;margin-bottom:18px}.banner-copy .training-title{font-size:32px;line-height:1.5}.course-guide{font-size:16px;line-height:1.95;color:#616168;margin:0 0 38px;max-width:1000px}
@media(max-width:900px){.welcome{gap:28px;grid-template-columns:1fr 1fr}.training-rationale{padding:32px;gap:32px}.intro .training-title{font-size:30px}.training-subtitle{font-size:21px}.banner-copy .training-title{font-size:27px}}
@media(max-width:650px){.welcome{display:flex;padding-top:0;gap:28px}.intro .training-title{font-size:28px}.intro .training-summary{font-size:15px;line-height:1.9}.intro .intro-art{height:185px;max-height:none}.training-subtitle{font-size:21px;margin-bottom:18px}.training-rationale{display:block;padding:28px 24px;margin-top:36px}.rationale-lead h2{font-size:24px}.rationale-argument{margin-top:32px}.rationale-argument>h2{font-size:23px}.collection-banner{min-height:0}.collection-banner img{position:relative;inset:auto;width:100%;height:210px;object-position:center 40%}.banner-copy{max-width:100%;padding:26px}.banner-copy .training-title{font-size:27px}.course-guide{font-size:15px}.form-pair{grid-template-columns:1fr;gap:0}}

.intro .intro-art{object-position:center 65%}

/* Preserve the classroom and activity context without cropping the illustrations. */
.intro .intro-art{object-fit:contain;object-position:center;background:transparent}
.collection-banner img{object-fit:contain;object-position:center}
.banner-copy .project-label{max-width:none}