@import url('data:text/css,');
:root{--ink:#292923;--muted:#898a80;--accent:#c25e42;--line:#e7e6df;--cream:#f6f5f0}*{box-sizing:border-box}body{margin:0;font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif;color:var(--ink);font-size:14px}button,input,textarea,select{font:inherit}button,a,input,select,textarea{outline-offset:4px}button,a{touch-action:manipulation}button{cursor:pointer;border:0;border-radius:9px;padding:11px 15px;background:transparent;color:inherit}a{text-decoration:none;color:inherit}button:hover{filter:brightness(.94)}input,textarea,select{border:1px solid var(--line);border-radius:8px;padding:11px;background:white;color:var(--ink);width:100%}label{display:block;font-size:12px;line-height:1.7}label input,label select,label textarea{margin-top:6px}h1,h2,h3,p{margin-top:0}h2{font-size:17px}small{font-size:11px}.hidden{display:none!important}.primary{background:var(--accent);color:white;border-radius:9px;padding:12px 17px;display:inline-block}.outline{border:1px solid var(--line);background:white}.muted,.help,.empty{color:var(--muted)}.help{font-size:12px;line-height:1.8}.empty{text-align:center;padding:40px 12px;line-height:2}.brand{font-size:25px;font-weight:750;letter-spacing:2px}.brand span{font-weight:400}.brand small{display:block;font-size:9px;letter-spacing:5px;margin-top:8px;color:var(--muted)}.eyebrow{letter-spacing:3px;font-size:10px;color:var(--muted)}.toast{position:fixed;bottom:30px;left:50%;transform:translate(-50%,15px);background:#292923ee;color:white;padding:14px 22px;border-radius:10px;z-index:100;opacity:0;pointer-events:none;transition:.2s;max-width:90vw}.toast.show{opacity:1;transform:translate(-50%,0)}
.viewer{background:#eeeae2;min-height:100vh;display:flex;align-items:center;justify-content:center;gap:100px;padding:32px}.desktop-intro{width:370px}.desktop-intro h1{font-family:serif;font-size:62px;line-height:1.45;letter-spacing:5px;margin:80px 0 24px}.desktop-intro p{color:#858478}.intro-bottom{margin-top:100px;font-size:11px;color:#77786d}.intro-bottom a{display:block;margin-top:20px;color:var(--accent)}.dot{display:inline-block;width:6px;height:6px;background:var(--accent);border-radius:50%;margin-right:7px}.phone{width:390px;height:810px;max-height:94vh;min-height:650px;position:relative;overflow:hidden;background:#272822;color:white;border-radius:28px;box-shadow:0 30px 80px #25251f26;border:6px solid #fff}.demo-ribbon{text-align:center;background:#ece6dc;color:#796650;font-size:9px;line-height:24px}.viewer-head{position:absolute;top:37px;left:18px;right:18px;z-index:2;display:flex;align-items:center;gap:9px;font-size:12px}.avatar{background:#f4eee3;color:#60533d;padding:11px;border-radius:50%;font-family:serif}.viewer-head small{display:block;font-size:10px;color:#ffffff9c;margin-top:5px}.viewer-head b{max-width:210px;display:block;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.viewer-head #online{margin-left:auto;font-size:10px;background:#ffffff15;padding:7px;border-radius:16px}.stage{height:100%;position:absolute;inset:24px 0 0;background:radial-gradient(ellipse at 75% 33%,#ac8b72 0%,#716855 26%,#333e33 60%,#202821 100%)}#video{width:100%;height:60%;object-fit:contain;display:none;position:relative;z-index:3}#stage-placeholder{padding:120px 35px;position:relative}#stage-placeholder h2{font-family:serif;font-weight:400;font-size:57px;line-height:1.35;letter-spacing:8px;margin:15px 0 25px}#stage-placeholder .eyebrow{color:#ddceba;font-size:9px;letter-spacing:4px}#stage-message{font-size:12px;color:#e3dac8}.stage-tag{font-size:10px;letter-spacing:2px;border:1px solid #c5b49b66;border-radius:20px;padding:8px 13px}#stage-placeholder>small{display:block;font-size:9px;margin-top:28px;color:#d5cebd88}.stage-line{position:absolute;width:210px;height:300px;border:1px solid #e2c7ab44;border-radius:50%;right:-75px;top:70px;transform:rotate(25deg)}.audience-overlay{position:absolute;bottom:0;left:0;right:0;padding:16px 12px 12px;background:linear-gradient(transparent,#10170dcf)}.announcement{font-size:10px;color:#eee0bd;background:#ffffff12;border-radius:7px;padding:8px 10px;max-width:90%;margin-bottom:8px}.comments{max-height:112px;min-height:60px;overflow:auto;scrollbar-width:none;font-size:11px;line-height:1.8}.comments p{margin:4px 0;overflow-wrap:anywhere}.comments b{font-weight:400;color:#e1cbb2;margin-right:7px}.comments .empty{text-align:left;padding:15px 5px;color:#c2c4b5}.composer{display:flex;align-items:center;gap:6px;margin-top:12px}.composer button{padding:7px;color:#fff}.composer #bag{font-size:23px;line-height:18px}.composer #bag span{display:block;font-size:9px}.composer form{display:flex;background:#ffffff1b;border-radius:30px;flex:1;min-width:0}.composer input{border:0;background:none;color:white;font-size:11px;width:100%;padding:10px}.composer input::placeholder{color:#ffffff85}.composer form button{font-size:11px;white-space:nowrap}.composer #like{font-size:28px}.product{display:flex;align-items:center;gap:10px;background:white;color:var(--ink);padding:12px;border-radius:10px;margin-top:12px}.product-art{width:58px;height:70px;background:linear-gradient(140deg,#ded2b9,#a9997c);display:flex;flex-direction:column;align-items:center;justify-content:center;color:#524632;font-family:serif;font-size:20px;flex-shrink:0}.product-art small{font-size:7px;letter-spacing:2px;margin-top:9px}.product-info{flex:1;min-width:0}.product-info b{display:block;font-size:12px;margin:5px 0}.product-info>small{font-size:9px;color:#8c7b63}.product-info p{font-size:10px;color:var(--muted);margin:6px 0}.product-info strong{font-size:18px;color:var(--accent)}.product button{font-size:10px;padding:10px}.compact{padding:9px}.compact .product-art{height:52px;width:45px;font-size:16px}.hint{position:absolute;bottom:272px;left:15px;background:#fff1d9;color:#895425;border-radius:7px;padding:9px 12px;font-size:11px;z-index:4}.gate{position:absolute;inset:24px 0 0;z-index:10;background:#f7f4edfa;color:var(--ink);display:flex;align-items:center;padding:32px}.gate-inner{width:100%}.gate-icon{width:50px;height:50px;border-radius:50%;background:#e6dcc9;color:#746248;display:grid;place-items:center;font:27px serif;margin-bottom:24px}.gate h2{font-size:26px}.gate p{font-size:12px;line-height:1.8;color:#8a887e}.gate .eyebrow{font-size:10px}.identity{display:flex;gap:12px;align-items:center;padding:14px 0;margin-bottom:12px;border-bottom:1px solid var(--line);font-size:12px}.identity>span{color:#66816b}.identity small{display:block;color:#99988c;margin-top:5px}.gate label{margin-top:12px}.code-row{display:flex;align-items:center;gap:8px}.code-row input{width:120px}.code-row button{white-space:nowrap;font-size:11px;color:var(--accent);padding:8px}.consent{display:flex;gap:7px;align-items:flex-start;font-size:10px!important;color:#89867c}.consent input{width:auto;margin:4px 0}.gate .primary{width:100%;margin-top:20px}.sheet{position:absolute;bottom:0;left:0;right:0;z-index:12;background:#f8f6f1;color:var(--ink);padding:10px 18px 24px;border-radius:20px 20px 0 0;box-shadow:0 -60px 150px #0008}.sheet-handle{width:30px;height:4px;background:#d7d3ca;border-radius:4px;margin:0 auto 18px}.sheet header{display:flex;justify-content:space-between}.sheet h3{margin:5px 0;font-size:21px}.sheet header small{font-size:9px;color:var(--muted);letter-spacing:2px}.sheet header button{font-size:26px}.sheet-note{font-size:10px;color:var(--muted);text-align:center;margin:20px 0 0}
.admin{background:var(--cream)}.sidebar{position:fixed;left:0;top:0;bottom:0;width:220px;background:#eeeee6;padding:40px 25px}.nav-label{margin:65px 12px 18px;font-size:10px;color:#929487;letter-spacing:2px}.nav{display:block;width:100%;text-align:left;margin:8px 0;font-size:12px;padding:14px}.nav.active{background:#dfe2d5;color:#49583e}.sidebar-bottom{position:absolute;bottom:35px;font-size:11px;line-height:2;color:#777d6a}.workspace{margin-left:220px;padding:40px;max-width:1650px}.topbar{display:flex;justify-content:space-between;align-items:center;gap:20px;margin-bottom:25px}.topbar h1{font-size:28px;margin:8px 0}.top-actions{display:flex;gap:10px;align-items:center}.top-actions select{width:210px;font-size:12px}.top-actions button,.top-actions a{font-size:12px;white-space:nowrap}.notice{background:#eeeadc;border:1px solid #e6dfc8;color:#8a7958;font-size:11px;padding:13px 17px;border-radius:8px;margin-bottom:26px;line-height:1.7}.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-bottom:25px}.stats article{padding:22px;background:white;border:1px solid var(--line);border-radius:12px}.stats span{font-size:12px;color:#7f8475}.stats b{display:block;font-size:37px;font-weight:500;margin:14px 0 10px}.stats small{color:#999b92;font-size:10px}.control-grid,.connection-grid{display:grid;grid-template-columns:1fr 1fr;gap:22px}.panel{background:white;border:1px solid var(--line);border-radius:12px;padding:24px}.panel header{display:flex;justify-content:space-between;align-items:center;gap:12px;margin-bottom:24px}.panel h2{margin:0;font-size:16px}.pill{background:#f2f3ec;padding:6px 9px;border-radius:5px;font-size:10px;color:#7c8470;white-space:nowrap}#settings label{margin-bottom:15px}#settings .check{display:flex;align-items:center;gap:9px}#settings .check input{width:auto;margin:0}.share-box{border-top:1px solid var(--line);margin-top:22px;padding-top:18px}.share-box small{display:block;color:var(--muted);margin-bottom:10px}.share-box code{display:block;font-size:11px;overflow-wrap:anywhere;margin-bottom:12px}.share-box button{font-size:11px}.admin-comments{max-height:470px;overflow:auto}.comment-row{display:flex;justify-content:space-between;gap:12px;border-bottom:1px solid #eee;padding:16px 0}.comment-row b{font-size:11px;color:#8c8d80}.comment-row p{font-size:13px;margin:8px 0 0;overflow-wrap:anywhere}.text-button{color:var(--accent);font-size:11px;padding:6px;white-space:nowrap}.admin-product{display:flex;gap:13px;align-items:center;margin:18px 0}.admin-product>div:nth-child(2){flex:1}.admin-product b{font-size:12px}.admin-product p{font-size:11px;color:var(--muted);margin:9px 0 0}.admin-product button{font-size:11px}.hint-buttons{display:flex;flex-wrap:wrap;gap:10px;margin:20px 0}.hint-buttons button{font-size:11px}.integrity{background:#f5f5ef;border-radius:8px;padding:15px;font-size:11px;color:#818773;line-height:1.8}.integrity p{margin:8px 0 0}.table-wrap{overflow:auto}table{width:100%;border-collapse:collapse;text-align:left;white-space:nowrap}th{font-size:11px;color:#8b8d80;font-weight:400;background:#f5f6f0;padding:14px}td{padding:18px 14px;border-bottom:1px solid var(--line);font-size:12px}td small{display:block;color:#999;margin-top:6px}.timeline-panel{margin-top:22px}.timeline{text-align:left;padding:0}.timeline>div{padding:14px 0;border-bottom:1px solid var(--line);display:flex;gap:20px;font-size:12px}.timeline time{color:#96998b}.timeline span{color:#7e8275}.connection-grid .panel{line-height:2}.connection-grid .pill{display:inline-block;margin:20px 0}.connection-grid p{font-size:13px;color:var(--muted)}
@media(max-width:1100px){.sidebar{width:180px;padding:30px 16px}.workspace{margin-left:180px;padding:25px}.topbar{align-items:flex-start;flex-direction:column}.desktop-intro{width:280px}.viewer{gap:40px}.desktop-intro h1{font-size:48px}.stats{gap:10px}.stats article{padding:16px}.stats small{line-height:1.5;display:block}}@media(max-width:700px){.viewer{padding:0;background:#272822}.desktop-intro{display:none}.phone{width:100%;height:100dvh;max-height:none;min-height:600px;border:0;border-radius:0;box-shadow:none}.sidebar{position:static;width:auto;padding:20px;display:flex;align-items:center;gap:5px}.sidebar .brand{font-size:18px;margin-right:auto}.sidebar .brand small,.sidebar-bottom,.nav-label{display:none}.nav{width:auto;font-size:10px;margin:0;padding:10px}.workspace{margin:0;padding:20px}.top-actions{flex-wrap:wrap}.top-actions select{width:100%}.stats{grid-template-columns:1fr 1fr}.control-grid,.connection-grid{grid-template-columns:1fr}.panel{padding:20px}.gate{padding:32px;justify-content:center}.gate-inner{max-width:330px}.timeline>div{flex-wrap:wrap}}
.demo-ribbon{position:relative;z-index:5}.desktop-intro{width:420px}.desktop-intro h1{font-size:54px}@media(max-height:800px){#stage-placeholder{padding-top:100px}#stage-placeholder h2{font-size:46px}#stage-placeholder>small{margin-top:18px}.desktop-intro h1{margin-top:60px}.intro-bottom{margin-top:70px}}@media(max-width:1100px){.desktop-intro{width:300px}.desktop-intro h1{font-size:42px}}@media(max-width:700px){#stage-placeholder{padding-top:110px}}
.connection-setup{margin-bottom:22px}.connection-row{padding:16px 0;border-top:1px solid var(--line);display:flex;flex-wrap:wrap;gap:12px;font-size:12px}.connection-row span{color:var(--accent)}.connection-row small{width:100%;color:var(--muted);overflow-wrap:anywhere}#generate-obs{margin-top:16px}#obs-result{border-top:1px solid var(--line);margin-top:20px;padding-top:20px}#obs-result label{margin-bottom:16px}
#video{position:absolute;top:72px;left:0;width:100%;height:49%;z-index:1;background:#151914}#player-notice{position:absolute;top:calc(49% + 78px);left:12px;right:12px;z-index:4;background:#20271fea;color:#f0e5d3;border-radius:7px;padding:9px;font-size:11px;line-height:1.6}#player-notice[hidden]{display:none}#player-retry{color:#ffd3b7;padding:5px 9px}.viewer-head{z-index:4}
/* Immersive room: video is the background; interactions stay above it. */
.phone{isolation:isolate}.stage{inset:0;height:100%;z-index:0}
#video{inset:0;width:100%;height:100%;object-fit:cover;object-position:center;z-index:0;background:#151914}
.stage::after{content:"";position:absolute;inset:0;pointer-events:none;background:linear-gradient(#0008,transparent 23%,transparent 53%,#0009);z-index:1}
.demo-ribbon{position:absolute;top:0;left:0;right:0;background:#191d1766;color:#eee6d7;font-size:8px;line-height:20px;pointer-events:none}
.viewer-head{z-index:4;top:32px;text-shadow:0 1px 4px #0008}
.live-controls{position:absolute;right:12px;top:86px;z-index:4;display:flex;gap:6px}
.live-controls button{background:#0005;color:white;border:1px solid #ffffff26;border-radius:20px;padding:7px 10px;font-size:10px}
.audience-overlay{z-index:3;background:linear-gradient(transparent,#0005);padding-top:35px;padding-bottom:max(12px,env(safe-area-inset-bottom));pointer-events:none}
.audience-overlay>*{pointer-events:auto}.comments{text-shadow:0 1px 3px #000b}.announcement{background:#0004}.composer form{background:#0005;border:1px solid #ffffff1a}
#player-notice{top:145px;left:20px;right:20px;z-index:2;background:#0006;text-align:center;backdrop-filter:blur(5px)}
@media(max-width:700px){.phone{min-height:0;height:100dvh}.viewer-head{top:calc(30px + env(safe-area-inset-top))}.live-controls{top:calc(84px + env(safe-area-inset-top))}}
/* Mobile classroom: readable touch targets, keyboard-aware viewport and safe areas. */
.gate{background:#f7f4ed;overflow-y:auto;overscroll-behavior:contain}
.sheet{max-height:80%;overflow-y:auto;overscroll-behavior:contain;padding-bottom:max(24px,env(safe-area-inset-bottom))}
@media(max-width:700px){
 body.viewer{height:100dvh;min-height:0;overflow:hidden;overscroll-behavior:none}
 .phone{height:var(--room-height,100dvh);width:100%;max-width:none;min-height:0}
 .demo-ribbon{padding-top:env(safe-area-inset-top);line-height:20px}
 .viewer-head b{max-width:min(52vw,260px)}
 .viewer-head #online{flex-shrink:0}
 .live-controls button{min-height:44px;font-size:12px;padding:10px 14px}
 .composer input,.gate input{font-size:16px}
 .composer button{min-width:44px;min-height:44px}
 .composer form button{font-size:14px}
 .comments{font-size:16px;line-height:1.65;max-height:20vh;min-height:45px}
 .announcement{font-size:14px;line-height:1.6}
 .audience-overlay{padding-left:max(12px,env(safe-area-inset-left));padding-right:max(12px,env(safe-area-inset-right))}
 .gate{inset:0;padding:calc(30px + env(safe-area-inset-top)) 24px max(24px,env(safe-area-inset-bottom));align-items:flex-start}
 .gate-inner{margin:auto;width:100%}
 .gate .code-row input{min-width:0;flex:1;width:0}
 .gate .code-row button{min-height:44px;font-size:13px}
 .gate .consent{font-size:12px!important}
 .gate .consent input{min-width:20px;min-height:20px}
 .sheet header button{min-width:44px;min-height:44px}
 .product button{min-height:44px;font-size:12px}
 .toast{bottom:calc(76px + env(safe-area-inset-bottom));width:max-content;text-align:center}
 .phone.keyboard-open .comments{max-height:12vh;min-height:0}
 .phone.keyboard-open #featured,.phone.keyboard-open .announcement,.phone.keyboard-open .live-controls{display:none}
}
@media(max-height:500px) and (max-width:700px){.gate-icon,.identity{display:none}.gate h2{margin-bottom:10px}.gate p{margin-bottom:10px}}

/* Readable WeChat viewer text; 16px inputs avoid iOS focus auto-zoom. */
@media(max-width:700px){
 .viewer{font-size:16px;-webkit-text-size-adjust:100%;text-size-adjust:100%}
 .viewer input,.viewer textarea,.viewer select{font-size:16px}
 .viewer-head{font-size:15px}
 .viewer-head small,.viewer-head #online{font-size:12px}
 .composer #bag span{font-size:12px;line-height:1.4}
 .composer input{min-width:0;line-height:1.5}
 .composer input::placeholder{color:#ffffffbf}
 .composer form button,.live-controls button{font-size:14px}
 .gate p,.gate label,.identity,.code-row button{font-size:15px}
 .identity small,.gate .help,.sheet-note{font-size:13px}
 .product-info b{font-size:15px;line-height:1.45}
 .product-info p,.product-info>small,.product button{font-size:13px}
 #stage-message,#player-notice,.hint{font-size:14px}
 .demo-ribbon{font-size:11px}
}

/* Classroom shopping and reactions */
#bag svg{width:32px;height:32px;display:block;margin:auto;filter:drop-shadow(0 2px 3px #0004)}
#bag{padding:2px 6px!important}
#like{color:#ff6687;font-size:34px;transition:transform .12s}
#like:active{transform:scale(1.3)}
#featured{position:relative;border-radius:12px}
#featured:not(:empty){margin-top:12px;box-shadow:0 0 0 2px #ffc64a,0 8px 24px #0005;background:white}
#featured .product{margin-top:0;border-radius:0 0 12px 12px}
.explaining-label{background:linear-gradient(100deg,#ffb82e,#ff7046);color:#fff;padding:5px 10px;border-radius:12px 12px 0 0;font-size:13px;font-weight:700}
.card-enter{animation:card-pop .6s cubic-bezier(.18,.8,.3,1.2)}
@keyframes card-pop{from{opacity:0;transform:translateY(45px) scale(.9)}to{opacity:1;transform:translateY(0) scale(1)}}
.sheet:not(.hidden){animation:sheet-up .25s ease-out}
@keyframes sheet-up{from{transform:translateY(100%)}to{transform:translateY(0)}}
#reactions{position:absolute;right:22px;bottom:80px;z-index:9;pointer-events:none}
#reactions span{position:absolute;bottom:0;right:0;font-size:32px;animation:reaction-float 1.8s ease-out both}
@keyframes reaction-float{0%{opacity:0;transform:scale(.4)}15%{opacity:1;transform:scale(1.15)}100%{opacity:0;transform:translate(var(--drift),-240px) rotate(var(--turn)) scale(.8)}}
#presentation-form label{margin-bottom:12px}#presentation-form fieldset{border:1px solid var(--line);border-radius:10px;margin:18px 0;padding:16px;min-width:0}
@media(prefers-reduced-motion:reduce){.card-enter,.sheet:not(.hidden){animation:none}#reactions span{animation-duration:.3s}}

#play-cover{position:absolute;inset:0;width:100%;height:100%;z-index:3;border-radius:0;background:rgba(70,70,70,.68);color:white;display:flex;align-items:center;justify-content:center;flex-direction:column;gap:15px;backdrop-filter:blur(2px)}
#play-cover .play-disc{display:grid;place-items:center;width:84px;height:84px;border:3px solid white;border-radius:50%;background:#ffffff26;font-size:34px;padding-left:5px;box-shadow:0 6px 30px #0003}
#play-cover strong{font-size:22px}#play-cover small{font-size:14px;color:#ffffffe6}

/* The keyboard must not vertically center a shorter classroom in the old body. */
@media(max-width:700px){
 body.viewer{align-items:flex-start;justify-content:flex-start}
 .viewer .phone{position:fixed;top:var(--room-top,0px);left:0;right:0;margin:0;height:var(--room-height,100dvh)}
}
/* TCPlayer stays beneath classroom overlays and follows the keyboard viewport. */
.fast-player-host{position:absolute;inset:0;z-index:0;background:#151914;overflow:hidden}
.fast-player-host>div,.fast-player-host .video-js,.fast-player-host video{position:absolute!important;inset:0!important;width:100%!important;height:100%!important;object-fit:cover!important}
.fast-player-host .vjs-control-bar,.fast-player-host .vjs-big-play-button,.fast-player-host .vjs-error-display,.fast-player-host .vjs-loading-spinner{display:none!important}

.playback-diagnostics{position:fixed;top:90px;left:8px;z-index:10000;white-space:pre-line;background:#000c;color:white;padding:8px;font:12px/1.6 monospace;pointer-events:none}