@charset "UTF-8";
:root{--navy:#163b40;--ink:#213b3d;--muted:#718080;--paper:#f7f6f1;--line:#e3e7e1;--orange:#da704b;--teal:#3c7777;--soft:#edf2ed;--white:#fff;--radius:18px}*{box-sizing:border-box}body{margin:0;background:var(--paper);font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif;color:var(--ink);font-size:15px;line-height:1.7}button,input,select{font:inherit}button,a,input,select{ -webkit-tap-highlight-color:transparent}button,a{touch-action:manipulation}a{color:inherit;text-decoration:none}button{cursor:pointer;color:inherit}button:disabled{opacity:.35;cursor:default}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible{outline:3px solid #edbc74;outline-offset:4px}[hidden]{display:none!important}.skip{position:absolute;top:-60px;left:16px;background:white;padding:10px;z-index:20}.skip:focus{top:10px}.topbar{height:88px;background:#fffefb;border-bottom:1px solid var(--line);padding:0 38px;display:flex;align-items:center;justify-content:space-between}.brand{display:flex;gap:13px;align-items:center;font-size:21px;font-weight:750;letter-spacing:.05em}.brand-mark{display:flex;align-items:center;justify-content:center;width:43px;height:47px;background:var(--navy);color:#fff;border-radius:10px 10px 17px 10px;font-family:Georgia,serif;font-size:27px}.brand-mark span{font-size:17px;align-self:flex-start;margin-top:6px}.brand small{display:block;font-size:10px;font-weight:450;letter-spacing:.17em;color:var(--muted);margin-top:0}.top-right{display:flex;align-items:center;gap:21px}.screen-note{font-size:12px;color:var(--muted)}.icon-btn{border:1px solid var(--line);border-radius:50%;background:white;width:31px;height:31px;font-family:Georgia;font-size:18px}.layout{display:grid;grid-template-columns:246px minmax(0,1fr);max-width:1580px;margin:auto}.sidebar{background:#fdfcf8;border-right:1px solid var(--line);padding:34px 20px 28px;align-self:start;position:sticky;top:0;max-height:100vh;overflow-y:auto}.sidebar-head{padding:0 11px 22px}.eyebrow{font-size:10px;letter-spacing:.12em;color:var(--muted);display:block;text-transform:uppercase;font-weight:650}.sidebar-head strong{font-size:15px;display:block;margin-top:6px}.lesson-item{display:flex;gap:12px;padding:12px 11px;align-items:flex-start;border-radius:10px;margin:3px 0;border:1px solid transparent;background:none;text-align:left;width:100%}.lesson-item:hover{background:#eef2ed}.lesson-item.active{background:#e6eeea;border-color:#d5e2db}.lesson-index{font-size:12px;font-family:Georgia;color:#84928e;padding-top:2px;min-width:19px}.lesson-item.active .lesson-index{color:var(--teal)}.lesson-item strong{display:block;font-size:12px;font-weight:600;line-height:1.7}.lesson-item small{display:block;font-size:10px;color:var(--muted);margin-top:2px}.done-dot{margin-left:auto;font-size:13px;color:var(--teal)}.sidebar-foot{border-top:1px solid var(--line);margin:25px 10px 0;padding-top:20px;font-size:11px}.sidebar-foot p{font-size:10px;color:var(--muted);margin-top:14px}.progress-track{height:4px;background:#e5ebe5;border-radius:5px;margin-top:9px}.progress-track i{display:block;background:var(--teal);height:100%;border-radius:5px;width:0;transition:width .3s}main{padding:32px 38px 0;min-width:0}.hero{background:var(--navy);border-radius:var(--radius);color:#fffef9;display:flex;min-height:270px;padding:32px 40px;position:relative;overflow:hidden;justify-content:space-between}.light{color:#a1c1b6;font-size:9px;letter-spacing:.16em}.hero h1{font-size:34px;line-height:1.45;font-weight:600;letter-spacing:.05em;margin:10px 0 13px}.hero p{font-size:12px;color:#c2d1ca;line-height:1.9;margin:0}.hero-tags{display:flex;gap:9px;margin-top:22px;flex-wrap:wrap}.hero-tags span{font-size:10px;border:1px solid #43605f;color:#cfddd6;padding:3px 9px;border-radius:4px}.hero-art{width:265px;position:relative;margin-right:0;flex-shrink:0}.orbit{position:absolute;border:1px solid #31565a;border-radius:50%;width:235px;height:110px;transform:rotate(-25deg);top:50px;left:0}.orbit-two{transform:rotate(48deg);height:140px;top:48px}.atom-dot{position:absolute;background:#dca46c;width:8px;height:8px;border-radius:50%}.d1{top:60px;left:185px}.d2{top:162px;left:35px;background:#98b4a3}.molecule{position:absolute;display:flex;align-items:center;gap:7px;top:69px;left:43px;transform:rotate(-12deg)}.molecule span{width:48px;height:48px;border-radius:50%;display:grid;place-items:center;background:#cbd9ba;color:var(--navy);font-size:18px;font-weight:650}.molecule b{width:68px;height:68px;border-radius:50%;display:grid;place-items:center;background:#dca46c;color:var(--navy);font-size:25px}.paper-shape{position:absolute;right:2px;bottom:8px;transform:rotate(10deg);padding:13px 30px 11px 15px;background:#f4f1d9;color:var(--navy);font-size:12px;box-shadow:0 6px 15px #071f2338;line-height:1.8}.paper-shape i{position:absolute;right:9px;bottom:14px;color:var(--orange);font-size:21px;font-style:normal}.section-tabs{display:flex;border-bottom:1px solid #dde3dc;margin:28px 0 28px;gap:28px;overflow:auto}.section-tabs button{border:0;background:none;white-space:nowrap;padding:0 0 13px;font-size:13px;color:var(--muted);position:relative}.section-tabs button.active{font-weight:700;color:var(--navy)}.section-tabs button.active:after{content:"";position:absolute;height:3px;background:var(--orange);bottom:0;left:0;right:0;border-radius:3px}.lesson-intro{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-bottom:24px}.lesson-kicker{display:flex;align-items:center;gap:11px;font-size:9px;letter-spacing:.13em;color:var(--muted);font-weight:650}.tag{background:#e7ece2;color:#5d7362;padding:2px 7px;border-radius:4px;font-size:9px;letter-spacing:0}.lesson-intro h2{font-size:27px;font-weight:650;line-height:1.5;margin:9px 0 5px}.muted{color:var(--muted)}.lesson-intro p{font-size:12px;margin:0}.teacher-chip{display:flex;gap:10px;align-items:center;font-size:12px;flex-shrink:0}.teacher-avatar{border-radius:50%;width:40px;height:40px;display:grid;place-items:center;background:#e7e5d5;font-size:16px;font-family:serif}.teacher-chip small{display:block;font-size:9px;color:var(--muted)}.listen-grid{display:grid;grid-template-columns:minmax(0,1.7fr) minmax(240px,1fr);gap:20px}.player-card{border-radius:var(--radius);padding:22px 27px 17px;background:#fff;box-shadow:0 5px 20px #163b4005;border:1px solid var(--line)}.player-top{display:flex;align-items:center;justify-content:space-between;gap:10px}.status{font-size:9px;background:#fbf0e3;color:#93682f;padding:3px 7px;border-radius:4px}.status.ready{background:#eaf1e9;color:#40694d}.wave{height:85px;display:flex;align-items:center;justify-content:center;gap:5px;margin:10px 0 0}.wave i{display:block;width:4px;border-radius:4px;background:#c9d8cf;height:20px}.wave i:nth-child(3n){height:40px}.wave i:nth-child(4n){height:57px;background:#749a8b}.wave i:nth-child(5n){height:31px}.wave i:nth-child(7n){height:66px;background:var(--teal)}.playing .wave i{animation:beat .8s ease-in-out infinite alternate}.playing .wave i:nth-child(2n){animation-delay:.2s}.playing .wave i:nth-child(3n){animation-delay:.4s}@keyframes beat{from{transform:scaleY(.5)}to{transform:scaleY(1.15)}}.segment-label{font-size:11px;text-align:center;color:var(--muted);margin:0 0 12px;min-height:19px}#seek{width:100%;height:4px;accent-color:var(--teal);margin:0}.time-row{display:flex;justify-content:space-between;font-size:10px;font-variant-numeric:tabular-nums;color:#97a29b;margin-top:4px}.play-controls{display:flex;justify-content:center;align-items:center;gap:23px;margin:15px 0 18px}.play-btn{display:flex;align-items:center;justify-content:center;gap:10px;background:var(--navy);color:white;border:0;border-radius:30px;min-width:160px;min-height:48px;font-size:13px;padding:12px 20px}.play-btn:hover{background:#23565a}.round-btn{border:0;background:none;font-size:25px;position:relative;line-height:1;width:28px;height:32px}.round-btn small{font-size:8px;position:absolute;left:8px;top:13px}.player-bottom{display:flex;align-items:center;justify-content:space-between;gap:10px;font-size:10px}.player-bottom label{display:flex;align-items:center;gap:5px;color:var(--muted)}select{border:1px solid #e1e7e0;background:#f8faf7;border-radius:5px;padding:3px;font-size:11px;color:var(--ink)}.text-btn{border:0;background:none;font-size:12px;padding:0;color:var(--teal);text-align:left}.player-bottom .text-btn,.player-bottom a{font-size:10px;color:var(--teal)}.player-note{font-size:10px;line-height:1.75;color:#8c938b;border-top:1px solid #eef1ec;padding-top:12px;margin:13px 0 0}.message{font-size:11px;color:#a05730;margin-top:6px}.paper-card{border-radius:var(--radius);background:#ecefe3;border:1px solid #e1e6d8;padding:23px 24px}.paper-card-head{display:flex;gap:10px;align-items:center;margin:14px 0}.paper-card h3{font-size:18px;margin:0}.paper-icon{font-size:26px;color:#6f876d}.checklist{list-style:none;padding:0;font-size:12px;line-height:2.1;margin:0}.checklist li:before{content:"✓";margin-right:9px;color:#6e886d}.book-reference{font-size:11px;color:#5d715d;margin:15px 0 0;padding-top:13px;border-top:1px solid #d7e0d0}.small{font-size:10px;line-height:1.8}.button{border:0;display:inline-flex;justify-content:center;align-items:center;border-radius:8px;font-size:12px;padding:10px 16px;font-weight:600}.secondary{background:white;border:1px solid #d7e0d7;color:var(--navy)}.secondary:hover{background:#f1f6ef}.full{width:100%}.paper-card .button{font-size:11px;margin-top:6px}.flow-strip{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;padding:25px 6px;}.flow-strip>div{display:flex;gap:9px;align-items:flex-start}.flow-strip b{font-family:Georgia;font-size:20px;font-weight:400;color:#b2bcb0;line-height:1.4}.flow-strip span{font-size:11px;font-weight:600}.flow-strip small{display:block;font-size:9px;color:var(--muted);font-weight:400;margin-top:2px}.goal-card{display:flex;gap:18px;align-items:flex-start;background:#f0f2eb;border:1px solid var(--line);border-radius:12px;padding:22px}.goal-icon{color:var(--orange);font-size:28px;line-height:1.2}.goal-card h3{font-size:15px;margin:6px 0 8px}.goal-card p{font-size:12px;color:#627369;margin:0;line-height:1.9}.completion-card{display:flex;align-items:center;justify-content:space-between;gap:18px;padding:24px 0;border-bottom:1px solid var(--line)}.completion-card strong{font-size:12px}.completion-card p{font-size:10px;color:var(--muted);margin:3px 0 0}.completion-toggle{display:flex;align-items:center;gap:8px;font-size:11px;white-space:nowrap}.completion-toggle input{accent-color:var(--teal);width:18px;height:18px}.lesson-nav{display:flex;align-items:center;justify-content:space-between;padding:22px 0}.panel-heading h2{font-size:25px;line-height:1.6;margin:9px 0}.panel-heading p{font-size:13px;color:var(--muted)}.role-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin:24px 0}.role-grid article{background:#fff;border:1px solid var(--line);border-radius:13px;padding:23px}.role-grid h3{font-size:15px;margin:8px 0}.role-grid p{font-size:12px;color:#6c7d73;line-height:1.9;margin-bottom:0}.role-label{font-size:10px;color:var(--orange)}.table-wrap{overflow:auto;background:white;border:1px solid var(--line);border-radius:13px}.plan-table{width:100%;border-collapse:collapse;font-size:12px;min-width:570px}.plan-table th{background:#eaf0e8;text-align:left;padding:12px 15px;font-size:11px}.plan-table td{border-top:1px solid #e9eee6;padding:13px 15px;line-height:1.8}.plan-table tr:nth-child(2n){background:#fbfcf8}.plan-table td:first-child{font-family:Georgia;font-size:18px;color:var(--teal);width:45px}.plan-table td:last-child{color:var(--muted)}.download-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin:26px 0}.download-card{display:block;background:white;border:1px solid var(--line);border-radius:14px;padding:25px;transition:transform .2s}.download-card:hover{transform:translateY(-3px);border-color:#a4b8a5}.file-type{font-size:10px;color:var(--orange)}.download-card h3{font-size:18px;margin:18px 0 9px}.download-card p{font-size:12px;color:var(--muted);line-height:1.9;min-height:70px}.download-card b{font-size:11px;color:var(--teal)}.qr-section{display:flex;gap:28px;padding:28px;border:1px solid var(--line);background:#eef1e8;border-radius:14px;margin-top:28px;align-items:center}.qr-section img{background:white;padding:8px;flex-shrink:0}.qr-section h3{font-size:17px;margin:0 0 8px}.qr-section p{font-size:12px;color:var(--muted)}.qr-section p.small{font-size:10px}.parent-actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:28px}.rule-box{border-left:3px solid var(--orange);padding:15px 20px;background:#f0f2ea;margin:25px 0}.rule-box h3{font-size:14px;margin-top:0}.rule-box p{font-size:12px;color:var(--muted);line-height:1.9}footer{border-top:1px solid var(--line);margin-top:28px;padding:22px 0 24px;color:#8a968e;font-size:10px}footer p{margin:3px 0}dialog{border:1px solid var(--line);border-radius:18px;max-width:670px;width:calc(100% - 32px);padding:35px;color:var(--ink);box-shadow:0 20px 80px #10282c30;max-height:85vh;line-height:1.9}dialog::backdrop{background:#163b4066;backdrop-filter:blur(3px)}dialog h2{font-size:24px;margin:10px 0 18px}dialog li,dialog p{font-size:13px}.close-dialog{float:right;width:30px;height:30px;border:0;background:#edf1ea;border-radius:50%;font-size:22px;line-height:1}#transcriptContent h3{font-size:13px;color:var(--teal);margin-top:25px}#transcriptContent p{font-size:14px}#transcriptContent .pause{font-size:11px;color:var(--orange)}
@media(min-width:1450px){main{padding-left:48px;padding-right:48px}.hero{padding:38px 45px}.hero h1{font-size:39px}.hero-art{margin-right:20px}}
@media(max-width:1100px){.layout{grid-template-columns:209px minmax(0,1fr)}main{padding:25px}.sidebar{padding:26px 12px}.hero{padding:28px}.hero h1{font-size:29px}.hero-art{width:210px;transform:scale(.85);transform-origin:right center;margin-left:-25px}.listen-grid{grid-template-columns:minmax(0,1.4fr) minmax(215px,1fr)}.player-card{padding:20px}.paper-card{padding:20px}.teacher-chip{display:none}.role-grid,.download-grid{gap:10px}.role-grid article,.download-card{padding:18px}.flow-strip{gap:6px}.flow-strip small{font-size:8px}}
@media(max-width:850px){.topbar{padding:0 23px;height:76px}.brand{font-size:18px}.screen-note{font-size:10px}.layout{display:block}.sidebar{position:static;max-height:none;border-right:0;border-bottom:1px solid var(--line);padding:12px 20px;background:#fbfcf7}.sidebar-head{display:none}#lessonList{display:flex;gap:6px;overflow-x:auto;padding:0 0 3px}.lesson-item{width:130px;flex-shrink:0;padding:9px;gap:6px}.lesson-item strong{font-size:10px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;max-width:95px}.lesson-item small{font-size:9px}.lesson-index{font-size:11px;min-width:15px}.done-dot{display:none}.sidebar-foot{display:none}main{padding:24px}.hero{min-height:245px}.hero-art{margin-right:3px}.listen-grid{grid-template-columns:minmax(0,1.6fr) minmax(220px,1fr)}.section-tabs{gap:30px}.lesson-intro h2{font-size:25px}}
@media(max-width:600px){body{font-size:14px}.topbar{height:70px;padding:0 17px}.brand{gap:9px;font-size:17px}.brand-mark{width:35px;height:39px;font-size:24px}.brand small{font-size:8px;letter-spacing:.1em}.top-right{gap:12px}.screen-note{display:none}.sidebar{padding:10px 14px}main{padding:18px 16px 0}.hero{min-height:235px;padding:26px 23px}.hero h1{font-size:28px;position:relative;z-index:1}.hero p{font-size:11px;position:relative;z-index:1}.hero .light{font-size:8px}.hero-tags{gap:5px;position:relative;z-index:1;margin-top:18px}.hero-tags span{font-size:8px;padding:3px 5px}.hero-art{position:absolute;right:-65px;top:20px;opacity:.25;transform:scale(.8);height:200px}.section-tabs{gap:25px;margin:23px 0}.section-tabs button{font-size:12px}.lesson-intro{margin-bottom:19px}.lesson-intro h2{font-size:24px;margin-top:9px}.lesson-intro p{font-size:11px}.listen-grid{grid-template-columns:1fr;gap:14px}.player-card{padding:21px 24px}.wave{height:84px;margin-top:8px}.paper-card{padding:20px 23px}.paper-card-head{margin:10px 0}.checklist{display:flex;flex-wrap:wrap;column-gap:15px;font-size:11px}.paper-card .small{margin:5px 0 12px}.paper-card .button{margin-top:0}.flow-strip{grid-template-columns:repeat(2,1fr);gap:20px 16px;padding:24px 5px}.flow-strip span{font-size:11px}.flow-strip small{font-size:9px}.goal-card{padding:18px;gap:12px}.goal-card h3{font-size:14px}.goal-card p{font-size:11px}.completion-card{align-items:flex-start;padding:22px 0}.completion-card p{max-width:205px}.completion-toggle{font-size:10px;padding-top:1px;gap:6px}.completion-toggle input{width:16px;height:16px}.role-grid,.download-grid{grid-template-columns:1fr;gap:12px}.role-grid article{padding:22px}.panel-heading h2{font-size:23px}.download-card{padding:24px}.download-card h3{margin-top:10px}.download-card p{min-height:0}.qr-section{flex-direction:column;align-items:flex-start;padding:24px;gap:18px}.qr-section img{align-self:center}.parent-actions .button{width:100%}dialog{padding:25px}footer{font-size:9px}}
.audio-package{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:24px 28px;border:1px solid var(--line);border-radius:14px;background:white;margin:20px 0}.audio-package h3{font-size:17px;margin:5px 0}.audio-package p{font-size:12px;color:var(--muted);margin:0}.audio-package a{white-space:nowrap}@media(max-width:600px){.audio-package{display:block;padding:23px}.audio-package a{display:flex;margin-top:15px;width:100%}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{animation:none!important;transition:none!important}}