:root{--ink:#19272a;--muted:#68777b;--green:#1c6655;--green-dark:#144c40;--mint:#e4eee7;--paper:#f5f6f3;--line:#e3e8e3;--white:#fff;--header:#182c29}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:var(--paper);color:var(--ink);font-family:Inter,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;font-size:14px;line-height:1.6;-webkit-font-smoothing:antialiased;min-height:100vh;display:flex;flex-direction:column}a{color:inherit;text-decoration:none}button,input{font:inherit}button,a,input{-webkit-tap-highlight-color:transparent}button{cursor:pointer}button:disabled{cursor:default}svg{width:22px;height:22px;flex-shrink:0;vertical-align:middle}h1,h2,h3,p{margin:0}button:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid #79b9a0;outline-offset:4px}[hidden]{display:none!important}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.skip-link{position:fixed;top:-70px;left:16px;padding:10px 18px;background:white;z-index:5;border-radius:8px}.skip-link:focus{top:10px}
.site-header{background:var(--header);color:#eaf0eb}.header-inner{max-width:1200px;padding:0 40px;margin:0 auto;height:82px;display:flex;align-items:center;justify-content:space-between;gap:24px}.brand{display:flex;align-items:center;gap:13px;font-size:18px;font-weight:650;letter-spacing:.025em;min-width:0}.brand>span:last-child{overflow-wrap:anywhere}.brand-icon{width:36px;height:36px;border:1px solid #507068;border-radius:10px;display:grid;place-items:center;color:#cee6d7;flex-shrink:0}.brand-icon svg{width:21px;height:21px}.main-nav{height:100%;display:flex;align-items:stretch;gap:36px;flex-shrink:0}.main-nav a{position:relative;display:flex;align-items:center;color:#aebfb9;padding:0 3px;font-weight:500}.main-nav a:hover,.main-nav .is-active{color:white}.main-nav .is-active:after{content:"";position:absolute;bottom:0;height:3px;left:0;right:0;background:#b7d4be;border-radius:3px 3px 0 0}
.page-shell{width:100%;max-width:1200px;margin:0 auto;padding:0 40px;flex:1}.home-page{padding-top:65px;padding-bottom:56px}.eyebrow{font-size:11px;letter-spacing:.12em;font-weight:650;color:var(--green);display:flex;align-items:center;gap:8px}.status-dot{width:6px;height:6px;border-radius:100%;background:#5f8a72}.welcome h1{font-size:52px;line-height:1.3;letter-spacing:-.04em;font-weight:650;margin:22px 0 20px}.welcome h1 span{color:var(--green)}.welcome-description{color:var(--muted);font-size:15px;max-width:680px;line-height:1.9;white-space:pre-line;overflow-wrap:anywhere}.entry-grid{display:grid;grid-template-columns:1fr 1fr;gap:24px;margin-top:42px}.entry-card{position:relative;background:white;border:1px solid var(--line);padding:30px 32px 26px;border-radius:18px;overflow:hidden;transition:transform .2s,border-color .2s,box-shadow .2s;display:block}.entry-card:hover{transform:translateY(-4px);border-color:#b4c7bb;box-shadow:0 14px 35px #243d2b09}.entry-icon{width:52px;height:52px;border-radius:14px;background:var(--mint);display:grid;place-items:center;color:var(--green);margin-bottom:23px}.entry-icon svg{width:26px;height:26px}.files-card .entry-icon{background:#e9eef5;color:#486079}.entry-number{position:absolute;top:23px;right:29px;font-size:48px;line-height:1;font-weight:300;color:#edf0eb;letter-spacing:-.05em}.entry-label{font-size:10px;letter-spacing:.14em;color:#7a8983;font-weight:600}.entry-card h2{font-size:28px;font-weight:650;margin:3px 0 12px;letter-spacing:.02em}.entry-card p{font-size:14px;color:var(--muted);line-height:1.9}.entry-bottom{display:flex;justify-content:space-between;align-items:center;gap:10px;margin-top:26px;padding-top:20px;border-top:1px solid #edf0ec;font-size:12px;color:#829089}.entry-bottom>span{display:flex;align-items:center;gap:6px}.entry-bottom svg{width:15px;height:15px}.entry-bottom .entry-action{font-weight:600;color:var(--green)}.entry-action svg{width:18px;height:18px;transition:transform .2s}.entry-card:hover .entry-action svg{transform:translateX(3px)}.home-note{display:flex;align-items:center;justify-content:center;gap:8px;color:#839089;font-size:12px;margin-top:29px}.home-note svg{width:16px;height:16px}.site-footer{padding:0 40px}.site-footer>div{max-width:1120px;margin:0 auto;border-top:1px solid #e0e6df;display:flex;justify-content:space-between;gap:15px;padding:24px 0 27px;font-size:11px;color:#87938c}.footer-dot{margin:0 7px;color:#afbab2}.site-footer a{display:inline-flex;align-items:center;gap:5px;white-space:nowrap}.site-footer a:hover{color:var(--green)}.site-footer svg{width:13px;height:13px}
.breadcrumb{display:flex;align-items:center;gap:11px;color:#8c9890;font-size:12px;margin:27px 0 31px}.breadcrumb>a:hover{color:var(--green)}.breadcrumb>span:last-child{color:#46594f}.locked-page{padding-bottom:68px}.unlock-card{max-width:460px;background:var(--white);border:1px solid var(--line);border-radius:18px;margin:42px auto 10px;padding:40px;box-shadow:0 10px 30px #253c2904}.unlock-icon{width:58px;height:58px;display:grid;place-items:center;border-radius:16px;background:var(--mint);color:var(--green);margin-bottom:27px}.unlock-icon svg{width:27px;height:27px}.unlock-card .eyebrow{font-size:10px;letter-spacing:.15em}.unlock-card h1{font-size:25px;letter-spacing:-.025em;line-height:1.5;margin:9px 0 10px;font-weight:650}.unlock-description{font-size:13px;color:var(--muted);line-height:1.9}.unlock-form{margin-top:27px}.unlock-form label{display:block;font-size:12px;font-weight:600;margin-bottom:9px}.password-field{position:relative}.password-field input{width:100%;height:48px;border:1px solid #dce3dd;background:#fcfdfb;border-radius:8px;padding:0 45px 0 14px;color:var(--ink)}input::placeholder{color:#9da7a1}.password-toggle{position:absolute;right:7px;top:7px;border:0;background:transparent;color:#7a8b80;width:34px;height:34px;border-radius:5px;display:grid;place-items:center}.password-toggle svg{width:18px;height:18px}.password-toggle:hover{background:#edf2ed}.button{min-height:41px;padding:9px 15px;border:1px solid transparent;border-radius:8px;display:inline-flex;align-items:center;justify-content:center;gap:9px;font-weight:600;font-size:12px;line-height:1.6;transition:background .15s,border-color .15s}.button svg{width:17px;height:17px}.primary-button{background:var(--green);color:white;width:100%;margin-top:14px;min-height:46px}.primary-button:hover{background:var(--green-dark)}.back-link{display:block;text-align:center;font-size:12px;color:#7a8880;margin-top:23px}.back-link:hover{color:var(--green)}.form-error,.notice{padding:12px 14px;border-radius:7px;font-size:12px;margin-top:18px;line-height:1.8}.form-error{background:#fff0ec;border:1px solid #f1d4cc;color:#a24b36}.notice{background:#f0f3eb;border:1px solid #e2e8d9;color:#5d6d4e}.subtle-button{background:#fff;border-color:#dce3dd;color:#65776c}.subtle-button:hover{background:#edf2ec;border-color:#bac9bd}
.collection-page{padding-bottom:65px}.section-heading{display:flex;justify-content:space-between;align-items:center;gap:20px;margin-bottom:30px}.section-heading .eyebrow{font-size:10px}.section-heading h1{font-size:32px;font-weight:650;line-height:1.5;display:flex;align-items:center;gap:16px;margin:3px 0 5px}.count-pill{font-size:10px;background:#e7eee7;color:#698071;font-weight:500;padding:3px 9px;border-radius:5px;letter-spacing:0}.section-heading p{color:var(--muted);font-size:13px}.logout-form{flex-shrink:0}.tutorial-layout{display:grid;grid-template-columns:minmax(0,1fr) 340px;gap:24px;align-items:start}.player-card,.lesson-panel,.files-panel{border:1px solid var(--line);border-radius:13px;background:white;overflow:hidden}.video-wrap{background:#13221f;aspect-ratio:16/9;display:flex;align-items:center;justify-content:center}.video-wrap video{display:block;width:100%;height:100%;max-height:70vh;object-fit:contain}.player-info{padding:22px 24px 24px}.category-tag{background:#eef3ed;color:#68806e;border-radius:4px;font-size:10px;padding:3px 7px;display:inline-block;max-width:100%;overflow-wrap:anywhere}.player-info h2{font-size:20px;font-weight:650;margin:9px 0 9px;line-height:1.6;overflow-wrap:anywhere}.player-info p{display:flex;align-items:center;gap:9px;font-size:11px;color:#8b9790;flex-wrap:wrap}.metadata-dot{color:#b7c0b8}.video-error{margin:0 24px 20px;color:#a24b36;background:#fff1ed;border-radius:7px;padding:12px;font-size:12px}.video-error a{text-decoration:underline;white-space:nowrap}.lesson-panel{padding-bottom:10px}.lesson-panel-heading{padding:20px 20px 13px;display:flex;justify-content:space-between;align-items:center;gap:10px}.lesson-panel-heading h2,.files-toolbar h2{font-size:14px;font-weight:650}.lesson-panel-heading>span{font-size:10px;color:#8b9790}.search-field{position:relative;display:flex;align-items:center;min-width:0}.search-field>svg{position:absolute;left:12px;width:16px;height:16px;color:#95a397;pointer-events:none}.search-field input{height:38px;width:100%;border-radius:7px;border:1px solid #e1e7df;background:#f7f9f5;padding:0 48px 0 36px;font-size:11px;min-width:0;color:var(--ink)}.search-hint{position:absolute;right:10px;font-size:9px;color:#9ca89e;pointer-events:none}.lesson-panel>.search-field{margin:0 16px 14px}.lesson-list{max-height:540px;overflow:auto;padding:0 9px;scrollbar-width:thin;scrollbar-color:#cbd7ca transparent}.lesson-item{display:flex;gap:10px;align-items:center;border-radius:7px;padding:13px 10px;margin:2px 0;transition:background .15s}.lesson-item:hover{background:#f4f7f0}.lesson-item.is-current{background:#edf4ed}.lesson-index{display:grid;place-items:center;width:27px;height:30px;color:#a0aca0;flex-shrink:0;font-size:12px;font-variant-numeric:tabular-nums}.lesson-index svg{width:20px;height:20px;color:var(--green)}.lesson-description{display:block;min-width:0;flex:1}.lesson-description strong{display:block;font-size:12px;font-weight:550;line-height:1.7;overflow-wrap:anywhere}.lesson-description>span{display:block;color:#91a08f;font-size:10px;margin-top:3px;overflow-wrap:anywhere}.lesson-description .metadata-dot{margin:0 3px}.is-current .lesson-description strong{color:var(--green)}.now-playing{color:#6a8a6f;font-size:9px;flex-shrink:0}.search-empty{padding:32px 22px;color:#8a988a;font-size:12px;text-align:center}.empty-state{text-align:center;background:white;border:1px solid var(--line);border-radius:14px;padding:70px 25px 62px}.empty-icon{width:64px;height:64px;border-radius:18px;background:var(--mint);color:#6f9074;display:grid;place-items:center;margin:0 auto 20px}.empty-icon svg{width:28px;height:28px}.empty-state h2{font-size:21px;margin-bottom:9px;font-weight:600}.empty-state p{font-size:13px;color:var(--muted)}.empty-state .button{margin-top:24px}
.files-toolbar{display:flex;align-items:center;justify-content:space-between;gap:22px;padding:22px 25px}.files-toolbar .search-field{width:280px}.file-table-heading,.file-row{display:grid;grid-template-columns:minmax(0,1fr) 110px 120px 80px;column-gap:20px;align-items:center;padding:0 25px}.file-table-heading{min-height:40px;background:#f8faf5;border-top:1px solid #ecf0e8;border-bottom:1px solid #ecf0e8;font-size:10px;color:#8d9b89}.file-table-heading>span:last-child{text-align:right}.file-row{padding-top:19px;padding-bottom:19px;border-bottom:1px solid #edf1e9}.file-row:last-child{border-bottom:0}.file-row:hover{background:#fcfdfb}.file-name{display:flex;align-items:center;gap:13px;min-width:0}.file-name>div{min-width:0}.file-icon{width:39px;height:43px;display:grid;place-items:center;background:#edf2e9;color:#789273;border-radius:7px;flex-shrink:0}.file-icon svg{width:21px;height:21px}.file-name h3{font-size:12px;font-weight:600;overflow-wrap:anywhere;line-height:1.7}.file-name p{font-size:10px;color:#9ca894;margin-top:3px;overflow-wrap:anywhere}.file-size,.file-date{font-size:11px;color:#83927c;font-variant-numeric:tabular-nums}.download-link{justify-self:end;display:inline-flex;align-items:center;gap:6px;color:var(--green);font-size:11px;padding:7px 0 7px 8px;white-space:nowrap}.download-link svg{width:15px;height:15px}.download-link:hover{color:#102e26;text-decoration:underline}.files-bottom-note{display:flex;align-items:center;gap:7px;border-top:1px solid #edf1e9;background:#fcfdfb;padding:15px 25px;color:#91a187;font-size:10px}.files-bottom-note svg{width:13px;height:13px}
@media(min-width:1400px){.home-page{padding-top:75px}.welcome h1{font-size:57px}.entry-grid{margin-top:46px}.entry-card{padding:35px 36px 29px}.entry-card p{line-height:2}}
@media(max-width:1000px){.tutorial-layout{grid-template-columns:minmax(0,1fr) 300px;gap:17px}.page-shell,.header-inner{padding-left:28px;padding-right:28px}.site-footer{padding-left:28px;padding-right:28px}.lesson-panel-heading{padding-left:17px;padding-right:17px}.file-table-heading,.file-row{grid-template-columns:minmax(0,1fr) 85px 100px 65px;column-gap:15px}.entry-card{padding-left:26px;padding-right:26px}}
@media(max-width:780px){.tutorial-layout{grid-template-columns:1fr}.lesson-list{max-height:400px}.lesson-panel{padding-bottom:14px}.video-wrap video{max-height:none}.section-heading{margin-bottom:25px}.home-page{padding-top:48px}.welcome h1{font-size:45px}.entry-grid{gap:16px;margin-top:34px}.entry-card{padding:25px 23px 22px}.entry-card h2{font-size:26px}.entry-bottom{flex-wrap:wrap;gap:12px}.file-table-heading,.file-row{grid-template-columns:minmax(0,1fr) 80px 90px 58px;column-gap:12px;padding-left:20px;padding-right:20px}.files-toolbar{padding-left:20px;padding-right:20px}.files-toolbar .search-field{width:240px}}
@media(max-width:560px){.header-inner{height:70px;padding:0 20px;gap:15px}.brand{font-size:15px;gap:9px;max-width:55%}.brand-icon{width:30px;height:30px;border-radius:8px}.brand-icon svg{width:18px;height:18px}.main-nav{gap:19px;font-size:12px}.page-shell{padding-left:20px;padding-right:20px}.home-page{padding-top:38px;padding-bottom:36px}.welcome .eyebrow{font-size:10px}.welcome h1{font-size:39px;margin:17px 0 17px}.welcome-description{font-size:13px;line-height:1.9}.entry-grid{grid-template-columns:1fr;gap:16px;margin-top:30px}.entry-card{padding:24px;border-radius:14px}.entry-icon{width:44px;height:44px;border-radius:12px;margin-bottom:17px}.entry-icon svg{width:23px;height:23px}.entry-card h2{font-size:25px;margin-bottom:8px}.entry-card p{font-size:12px}.entry-number{font-size:43px;top:23px;right:25px}.entry-bottom{margin-top:20px;padding-top:17px;flex-wrap:nowrap}.home-note{font-size:10px;align-items:flex-start;margin-top:22px}.home-note svg{width:14px;height:14px;margin-top:2px}.site-footer{padding:0 20px}.site-footer>div{font-size:10px;padding:20px 0;gap:20px}.footer-dot{margin:0 3px}.breadcrumb{margin:22px 0 26px;font-size:11px}.unlock-card{margin:25px auto 0;padding:28px 24px;border-radius:14px}.unlock-card h1{font-size:23px}.unlock-description{font-size:12px}.unlock-icon{width:50px;height:50px;border-radius:13px;margin-bottom:23px}.locked-page{padding-bottom:45px}.collection-page{padding-bottom:42px}.section-heading{gap:12px;align-items:flex-start}.section-heading h1{font-size:28px;gap:10px}.section-heading .eyebrow{font-size:9px}.section-heading p{font-size:12px}.count-pill{font-size:9px}.logout-form{padding-top:23px}.logout-form .button{font-size:10px;padding:7px 10px;min-height:34px;gap:5px}.logout-form svg{width:14px;height:14px}.player-info{padding:18px 20px 20px}.player-info h2{font-size:18px}.player-info p{font-size:10px}.files-toolbar{display:block;padding:18px}.files-toolbar h2{font-size:13px;margin-bottom:12px}.files-toolbar .search-field{width:100%}.files-toolbar input{font-size:12px}.file-table-heading{display:none}.file-row{grid-template-columns:minmax(0,1fr) auto;gap:6px 10px;padding:17px 18px;position:relative}.file-name{grid-column:1;grid-row:1;gap:10px}.file-icon{width:31px;height:37px;border-radius:6px}.file-icon svg{width:18px;height:18px}.file-name h3{font-size:12px}.file-name p{font-size:10px}.file-size{grid-column:1;grid-row:2;margin-left:41px;font-size:10px}.file-date{display:none}.download-link{grid-column:2;grid-row:1 / 3;font-size:11px;gap:4px;padding-left:3px}.download-link svg{width:14px;height:14px}.files-bottom-note{padding:13px 18px;font-size:9px}.empty-state{padding:50px 18px}.empty-state h2{font-size:19px}.empty-state p{font-size:12px}.search-field input{font-size:12px}}
.collection-error{margin:0 0 20px}
@media(max-width:560px){.file-date{display:block;grid-column:1;grid-row:3;margin-left:41px;font-size:10px}.download-link{grid-row:1 / 4}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}