:root{--paper:#f5f3ed;--white:#ffffff;--ink:#323232;--green:#545454;--muted:#7c7c7c;--line:#e0e0e0;--pale:#eeeeee;--accent:#c9724d;--warn:#9d5d3e}*{box-sizing:border-box}body{margin:0;color:var(--ink);background:var(--paper);font:15px/1.65 Inter,ui-sans-serif,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;-webkit-font-smoothing:antialiased}.shell{max-width:1180px;margin:auto;padding:0 40px}header{min-height:92px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;gap:24px}.brand{text-decoration:none;color:var(--ink);font-size:27px;font-weight:650;letter-spacing:-1.6px;display:flex;gap:2px;align-items:center}.brand>span:last-child{color:var(--accent)}.logo{color:var(--green);font-size:35px;margin-right:9px;transform:rotate(180deg)}nav{display:flex;gap:27px;font-size:12px}a{color:var(--green)}nav a{text-decoration:none;color:var(--muted);padding:8px 0}nav a.current{color:var(--green);box-shadow:0 2px 0 var(--green)}button,select,input{font:inherit}button,a,select,input{touch-action:manipulation}button{cursor:pointer}button:disabled{cursor:default;opacity:.45}.connection{display:flex;align-items:center;gap:8px;border:1px solid var(--line);background:var(--white);border-radius:24px;padding:9px 15px;font-size:11px;color:var(--green);max-width:240px}.connection span:last-child{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}#connectionDot{width:7px;height:7px;min-width:7px;background:#a5a5a5;border-radius:50%}#connectionDot.on{background:#828282;box-shadow:0 0 0 3px #e8e8e8}.eyebrow{font-size:10px;letter-spacing:1.8px;font-weight:650;color:var(--green);margin:0 0 14px}h1,h2,h3{font-family:Georgia,"Times New Roman",serif;font-weight:400;line-height:1.12}h1{font-size:clamp(38px,4.6vw,58px);letter-spacing:-1.9px;margin:0 0 20px}h1 em{color:var(--green)}h2{font-size:31px;letter-spacing:-.7px;margin:0 0 14px}h3{font-size:24px;letter-spacing:-.4px;margin:0 0 12px}p{margin:0 0 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p{font-size:12px;color:var(--muted);flex:1}.card-bottom{display:flex;justify-content:space-between;gap:12px;align-items:center;font-size:11px;color:var(--green);margin-top:14px}.pill{font-size:10px;padding:4px 8px;background:var(--pale);border-radius:4px;color:var(--green)}.song-banner{display:flex;justify-content:space-between;align-items:center;gap:30px;padding:30px 32px;margin:26px 0;background:#373737;border-radius:13px;color:var(--white)}.song-banner h2{font-size:29px;margin-bottom:9px}.song-banner p{color:#c8c8c8;font-size:13px;margin:0}.song-banner .eyebrow{color:#cacaca;margin-bottom:11px}.song-banner .secondary{color:white;border-color:#959595;white-space:nowrap}.info-line{font-size:12px;color:var(--muted);margin:24px 0}.breadcrumb{padding:28px 0 0;font-size:12px}.breadcrumb a{text-decoration:none}.lesson-header{margin:23px 0 28px;max-width:820px}.lesson-header h1{font-size:42px}.lesson-header p{max-width:700px;color:var(--muted)}.reading-grid{display:grid;grid-template-columns:1.5fr 1fr;gap:28px;align-items:start}.reading{padding:30px;background:var(--white);border:1px solid var(--line);border-radius:13px}.reading article+article{border-top:1px solid var(--line);padding-top:23px;margin-top:23px}.reading h3{font-size:23px}.reading p{font-size:14px;line-height:1.85;color:#6c6c6c}.side-note{background:var(--pale);padding:27px;border-radius:13px}.side-note h3{font-size:26px}.side-note p{font-size:13px;color:#6f6f6f}.finger-list{display:grid;grid-template-columns:repeat(5,1fr);gap:6px;margin:24px 0}.finger-list span{display:flex;flex-direction:column;align-items:center;font-size:9px;padding:12px 3px;background:#f3f3f3;border-radius:5px}.finger-list b{font:25px Georgia,serif;margin-bottom:9px;color:var(--green)}.read-actions{border-top:1px solid var(--line);padding-top:20px;margin-top:25px}.notice{padding:14px 17px;background:#f2f2f2;border-radius:7px;font-size:12px;color:#707070;margin:17px 0}.source-row{display:flex;align-items:center;gap:16px;margin:23px 0 16px;flex-wrap:wrap}.source-row label{font-size:12px;font-weight:600}.source-row select{width:auto;font-size:12px;min-height:39px;max-width:100%}.source-label{font-size:11px;color:var(--muted);flex:1}.workbench{background:var(--white);border:1px solid var(--line);border-radius:15px;padding:28px}.workbench-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:19px}.workbench-head span{font-size:11px;color:var(--muted)}.progress-track{height:5px;background:#efefef;border-radius:5px;overflow:hidden}.progress-track div{height:100%;background:var(--green);transition:width .2s}.exercise-main{display:grid;grid-template-columns:1fr 1fr;gap:25px;padding:25px 0 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4px;z-index:2;color:white}.piano-key:disabled{opacity:1;cursor:default}.piano-key.white.active{background:#cdcdcd;border-bottom-color:#9b9b9b;color:#424242}.piano-key.black.active{background:#9a9a9a;border-bottom-color:#5f5f5f}.piano-key.hint{box-shadow:inset 0 -7px 0 var(--accent)}.piano-key.demo{box-shadow:inset 0 -7px 0 #779ccb}.mini-keys .piano{height:95px;min-width:220px}.mini-keys .piano-key.black{width:8.6%;height:63%}.keyboard-note{font-size:11px;color:var(--muted);margin:9px 0}.lower-actions{display:flex;justify-content:space-between;align-items:center;gap:18px;flex-wrap:wrap;margin-top:19px}.stat-row{display:flex;gap:30px;margin:23px 0;flex-wrap:wrap}.stat{padding-right:26px;border-right:1px solid var(--line)}.stat:last-child{border:0}.stat b{display:block;font:31px Georgia,serif;color:var(--green)}.stat span{font-size:11px;color:var(--muted)}.result-panel{padding:35px;border:1px solid var(--line);border-radius:13px;background:var(--white);margin:20px 0}.result-panel>p{max-width:650px;color:var(--muted)}.ear-progress{font-size:12px;color:var(--muted);margin:10px 0 25px}.ear-choice{display:flex;gap:12px;flex-wrap:wrap;margin-top:25px}.ear-choice button{min-width:135px}.ear-feedback{min-height:32px;margin-top:18px;font-size:13px}.song-controls{display:flex;gap:18px;flex-wrap:wrap;align-items:center;margin:18px 0 23px}.song-controls label{font-size:12px;display:flex;gap:8px;align-items:center}.song-controls select{width:auto;min-height:38px}.song-controls input[type=range]{max-width:120px;accent-color:var(--green)}.melody-bars{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;margin:22px 0}.bar{padding:17px 12px;border:1px solid var(--line);background:#f7f7f7;border-radius:8px}.bar-label{font-size:9px;letter-spacing:1px;color:var(--muted);margin-bottom:13px}.note-chips{display:flex;gap:5px;justify-content:space-between}.note-chip{flex:1;min-width:0;text-align:center;border-radius:4px;padding:8px 2px;font-size:16px;color:#767676;background:#eeeeee;line-height:1.3}.note-chip small{display:block;font-size:9px;color:#939393;margin-top:4px}.note-chip.current{background:var(--green);color:white;outline:2px solid #aeaeae;outline-offset:2px}.note-chip.current small{color:#e3e3e3}.note-chip.done{background:#dcdcdc;color:#4d4d4d}.audio-message{min-height:25px;font-size:12px;color:var(--muted);margin-top:15px}.check-row{display:flex;align-items:center;gap:10px;font-size:12px;margin:16px 0}.check-row input{accent-color:var(--green);width:16px;height:16px}select{width:100%;border:1px solid #d2d2d2;min-height:43px;border-radius:7px;padding:8px 10px;background:var(--white);color:var(--ink)}footer{display:flex;justify-content:space-between;align-items:center;gap:25px;padding:34px 0 25px;margin-top:32px;border-top:1px solid var(--line);color:#8f8f8f;font-size:10px}footer span{letter-spacing:1px;font-size:9px}footer p{margin:0;text-align:right;max-width:340px}dialog{border:1px solid var(--line);border-radius:16px;padding:28px;max-width:460px;width:calc(100% - 32px);background:var(--white);color:var(--ink);box-shadow:0 20px 70px #29292930}dialog::backdrop{background:#282828a8}.dialog-top{display:flex;justify-content:space-between;align-items:center}.dialog-top .eyebrow{margin:0}.icon-button{font-size:24px;border:0;background:transparent;color:var(--muted);padding:0 6px}dialog h2{font-size:34px;margin-top:20px}dialog p{font-size:13px;color:var(--muted)}dialog label{font-size:11px;display:block;margin:20px 0 6px}dialog .primary,dialog .secondary{width:100%}dialog .message{padding:12px 0;margin:0;min-height:55px}.dialog-help{display:block;margin:18px 0 0;font-size:11px;text-align:center}.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}[hidden]{display:none!important}:focus-visible{outline:3px solid var(--accent);outline-offset:4px}@media(max-width:800px){.shell{padding:0 22px}header{flex-wrap:wrap;padding:16px 0;gap:12px}.brand{font-size:25px}nav{order:3;width:100%;gap:24px;font-size:11px}.connection{font-size:10px}.hero{grid-template-columns:1fr;padding-top:35px;gap:22px}.hero-card{padding:22px}.hero-card .mini-keys{max-width:330px}.lesson-grid{grid-template-columns:1fr}.lesson-card{min-height:0;display:grid;grid-template-columns:45px 1fr;gap:0 14px;padding:23px}.lesson-number{grid-row:1/4;margin:2px 0 0;font-size:27px}.lesson-card h3{font-size:24px}.lesson-card p{margin:0}.card-bottom{grid-column:2}.reading-grid{grid-template-columns:1fr}.reading{padding:24px}.lesson-header h1{font-size:37px}.side-note{padding:24px}.exercise-main{grid-template-columns:1fr;gap:12px}.target-panel{min-height:190px}.feedback-panel{padding:12px 3px}.feedback{min-height:0}.workbench{padding:20px}.song-banner{padding:25px;flex-direction:column;align-items:flex-start}.melody-bars{grid-template-columns:repeat(2,1fr)}.note-chip{font-size:20px}.bar{padding:16px}.stat-row{gap:18px}.stat{padding-right:18px}.result-panel{padding:25px}.section-title{align-items:flex-start;gap:20px}.section-title span{max-width:115px;text-align:right}footer{align-items:flex-start;gap:20px}.ear-choice{flex-direction:column}.ear-choice button{width:100%}}@media(prefers-reduced-motion:reduce){*{transition:none!important}}

@media(max-width:480px){.melody-bars{grid-template-columns:1fr}.song-controls label{flex-wrap:wrap}.source-label{flex-basis:100%}}
.course-summary .program-numbers{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin:12px 0 20px}.program-numbers strong{font-size:35px}.program-numbers span{font-size:11px;color:var(--muted)}.course-stage-tabs{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin:12px 0 34px}.stage-tab{text-align:left;border:1px solid var(--line);border-radius:10px;padding:18px 20px;background:transparent;color:var(--muted)}.stage-tab span{display:block;font-size:9px;letter-spacing:1.3px}.stage-tab b{display:block;font:24px Georgia,serif;color:var(--ink);margin:5px 0}.stage-tab small{font-size:10px}.stage-tab.selected{background:var(--green);border-color:var(--green);color:#d1d1d1}.stage-tab.selected b{color:white}.module-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}.module-card{display:grid;grid-template-columns:50px 1fr;gap:18px;padding:25px;border:1px solid var(--line);background:var(--white);border-radius:12px;text-decoration:none}.module-card:hover{border-color:#b6b6b6}.module-id{font:27px Georgia,serif;color:#a1a1a1}.module-card h3{font-size:25px;color:var(--ink);margin-bottom:8px}.module-card p{font-size:12px;color:var(--muted);min-height:40px}.module-card .card-bottom{flex-wrap:wrap}.course-note{display:flex;gap:15px;padding:22px;background:#eeeeee;border-radius:10px;margin:25px 0 18px}.course-note strong{font-size:13px;font-weight:600}.course-note p{font-size:12px;color:var(--muted);margin:4px 0 0}.note-mark{border:1px solid #a9a9a9;width:23px;height:23px;min-width:23px;border-radius:50%;text-align:center;font:italic 18px Georgia,serif}.module-feature{background:#ececec;padding:26px 28px;border-radius:12px;display:flex;align-items:center;gap:25px;justify-content:space-between}.module-feature h2{font-size:30px}.module-feature p:not(.eyebrow){font-size:13px;color:var(--muted);margin:0;max-width:620px}.module-feature .primary{flex-shrink:0}.curriculum-lessons{border:1px solid var(--line);border-radius:12px;background:var(--white);overflow:hidden}.curriculum-lesson+.curriculum-lesson{border-top:1px solid var(--line)}.curriculum-lesson summary{list-style:none;display:flex;align-items:center;gap:17px;padding:20px 22px;cursor:pointer}.curriculum-lesson summary::-webkit-details-marker{display:none}.lesson-index{color:#999999;font-size:12px;min-width:46px}.planned-title{font-size:14px;font-weight:500;flex:1}.lesson-state{font-size:10px;color:#929292;white-space:nowrap}.lesson-state.ready{color:var(--green);background:#eeeeee;padding:3px 7px;border-radius:4px}.expand-symbol{font-size:21px;color:#959595;font-weight:300}.curriculum-lesson[open] .expand-symbol{transform:rotate(45deg)}.lesson-plan{padding:0 24px 24px 85px}.lesson-plan>p{font-size:13px;color:var(--muted);max-width:790px}.criterion{background:#f3f3f3;padding:16px 19px;border-radius:7px;margin:16px 0}.criterion p{margin:6px 0 0;font-size:12px;color:#717171}.criterion .eyebrow{font-size:8px}.lesson-plan .small{font-size:11px;margin-top:10px}.module-test-plan{padding:28px;background:#ebebeb;margin:24px 0;border-radius:12px}.module-test-plan p{font-size:13px;color:var(--muted);max-width:760px}.rubric-legend{font-size:12px;color:var(--muted)}.rubric-legend summary{cursor:pointer}.rubric-legend p{margin-top:12px}
@media(max-width:800px){.module-grid{grid-template-columns:1fr}.course-stage-tabs{gap:7px}.stage-tab{padding:13px 10px}.stage-tab b{font-size:20px}.stage-tab small{font-size:9px}.module-card{padding:21px;grid-template-columns:43px 1fr;gap:12px}.module-card h3{font-size:23px}.module-feature{flex-direction:column;align-items:flex-start}.curriculum-lesson summary{padding:18px 15px;gap:9px;flex-wrap:wrap}.planned-title{font-size:13px}.lesson-state{font-size:9px}.lesson-plan{padding:0 20px 22px}.lesson-index{min-width:40px}.expand-symbol{font-size:18px}}