:root{--bg:#f6f7f8;--surface:#fff;--ink:#202832;--muted:#76808f;--line:#e5e8ec;--green:#205848;--green-light:#eaf5ef;--radius:10px;font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Microsoft YaHei",sans-serif;color:var(--ink);background:var(--bg);font-synthesis:none}
*{box-sizing:border-box}body{margin:0}button,input,a{font:inherit}button,a,input{-webkit-tap-highlight-color:transparent}button{cursor:pointer}button{color:inherit}button:disabled{opacity:.45;cursor:default}button:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid #82b9a8;outline-offset:3px}button{border:0}button,a{touch-action:manipulation}svg{width:24px;height:24px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round;flex-shrink:0}
.site-header{height:72px;background:var(--surface);display:flex;align-items:center;justify-content:space-between;padding:0 3.8%;border-bottom:1px solid #edf0f2;gap:24px}.brand{display:flex;align-items:center;gap:24px;min-width:0}.wordmark{font-size:30px;font-weight:760;letter-spacing:1px;color:#174e40;white-space:nowrap}.brand-subtitle{border-left:1px solid #a9b1bb;padding-left:24px;color:#525d6c;font-size:18px;white-space:nowrap}nav{display:flex;align-items:center;gap:20px}.header-button{font-size:18px;font-weight:600;background:none;padding:10px 0;white-space:nowrap}.nav-divider{height:24px;width:1px;background:#a9b1bb}
main{max-width:1487px;margin:0 auto;padding:26px 42px 20px}.page-heading{display:flex;align-items:center;margin:0 14px 26px;gap:26px}.page-heading h1{font-size:32px;line-height:1.4;letter-spacing:.4px;margin:0;font-weight:740}.page-heading p{font-size:18px;color:var(--muted);border-left:1px solid #a9b1bb;padding-left:26px;margin:0;line-height:1.5}.workspace{display:grid;grid-template-columns:382px minmax(0,1fr);gap:20px;align-items:start}.catalog{background:var(--surface);border-radius:var(--radius);padding:22px 24px 12px;min-height:760px;display:flex;flex-direction:column}.catalog-head{display:flex;justify-content:space-between;align-items:center;margin-bottom:22px}.catalog h2{font-size:26px;letter-spacing:.5px;margin:0;font-weight:700}.catalog-head>span{font-size:18px;color:#566170}.search{display:flex;align-items:center;gap:12px;background:#f9fafb;border:1px solid #d9dfe6;padding:0 13px;height:52px;border-radius:8px;margin-bottom:24px;color:#8c95a0}.search input{background:transparent;border:0;min-width:0;width:100%;font-size:17px;outline:none;color:var(--ink);height:100%}.search input::placeholder{color:#8b94a1}.search:focus-within{border-color:var(--green);box-shadow:0 0 0 2px #e4f0eb}.filters{display:flex;gap:9px;margin-bottom:24px}.filter{background:#f9fafb;border:1px solid #d6dce3;padding:11px 12px;border-radius:7px;font-size:17px;white-space:nowrap;flex:1;font-weight:500}.selected{background:var(--green)!important;color:white!important;border-color:var(--green)!important}.song-list{height:628px;overflow:auto;overscroll-behavior:contain;scrollbar-width:thin;scrollbar-color:#cdd2d7 transparent;margin:0 -15px 0 -16px;padding:0 10px 0 0}.song-list::-webkit-scrollbar{width:7px}.song-list::-webkit-scrollbar-thumb{background:#cdd2d7;border-radius:10px}.song{display:flex;align-items:center;width:100%;gap:20px;min-height:58px;background:transparent;position:relative;text-align:left;border-bottom:1px solid #eef0f3;padding:13px 14px 13px 24px;border-radius:0;font-size:18px;line-height:1.45}.song:hover{background:#f4f8f6}.song.active{background:var(--green-light);border-bottom-color:transparent;border-radius:5px}.song.active:before{content:"";position:absolute;top:1px;bottom:1px;left:0;width:5px;background:#2a705a;border-radius:4px}.song-number{font-size:17px;color:#7c8795;min-width:28px;font-variant-numeric:tabular-nums}.active .song-number{color:#477565}.song-title{flex:1;overflow-wrap:anywhere}.song-star{font-size:17px;color:#31715b}.list-summary{font-size:13px;color:var(--muted);padding:10px 0 0;min-height:27px}.list-summary:empty{display:none}.empty{color:var(--muted);padding:24px 16px;font-size:16px;line-height:1.7}
.practice{min-width:0}.player-panel{padding:18px 22px 6px;background:var(--surface);border-radius:var(--radius)}.track-header{display:flex;justify-content:space-between;align-items:flex-start;gap:16px;margin-bottom:18px}.track-header h2{font-size:30px;line-height:1.4;letter-spacing:.2px;margin:0 0 3px;font-weight:730}.track-header p{font-size:18px;color:#717c8b;margin:0;line-height:1.6}.favorite{display:flex;align-items:center;gap:8px;font-size:17px;margin-top:0}.favorite svg{width:20px;height:20px}.favorite[aria-pressed=true]{background:var(--green-light);color:var(--green);border-color:#b2d3c4}.favorite[aria-pressed=true] svg{fill:var(--green)}.button-outline{border:1px solid #cfd7df;border-radius:7px;background:#f9fafb;padding:11px 18px;line-height:1.3;font-size:17px;min-height:46px}.button-primary{border:1px solid var(--green);background:var(--green);color:white;border-radius:7px;padding:11px 18px;line-height:1.3;font-size:17px;min-height:46px;text-decoration:none;text-align:center}.button-primary:hover{background:#174736}.button-outline:hover{background:#eff3f2}.video-wrap{position:relative;background:#000;border-radius:9px;overflow:hidden;aspect-ratio:16/9}.video-wrap video{display:block;width:100%;height:100%;object-fit:contain;background:#000}.media-error{position:absolute;inset:0;margin:0;padding:24px;display:grid;place-content:center;text-align:center;color:white;background:#1b242ce8;font-size:17px;line-height:1.8}.media-error[hidden]{display:none}.practice-controls{display:flex;align-items:center;justify-content:space-between;gap:12px;border:1px solid var(--line);border-radius:8px;padding:10px;margin-top:14px;min-height:72px}.speed-controls{display:flex;align-items:center;gap:8px;white-space:nowrap}.speed-controls>span{font-size:15px;font-weight:550;margin-right:6px}.speed-controls button{min-width:59px;height:44px;padding:0 10px;border:1px solid var(--line);border-radius:8px;background:#f9fafb;font-size:16px;font-variant-numeric:tabular-nums}.loop-control{border-left:1px solid #d1d7dd;display:flex;align-items:center;gap:14px;padding-left:18px;font-size:15px;white-space:nowrap;cursor:pointer;position:relative}.loop-control input{position:absolute;opacity:0;width:44px;height:28px;right:0;margin:0;cursor:pointer}.switch{display:block;width:46px;height:27px;background:#c6cbd0;border-radius:18px;position:relative;pointer-events:none}.switch:after{content:"";position:absolute;left:3px;top:3px;width:21px;height:21px;background:white;border-radius:50%;box-shadow:0 1px 3px #0002;transition:transform .15s}.loop-control input:checked+.switch{background:var(--green)}.loop-control input:checked+.switch:after{transform:translateX(19px)}.loop-control input:focus-visible+.switch{outline:3px solid #82b9a8;outline-offset:3px}.track-navigation{display:flex;gap:10px;border-left:1px solid #d1d7dd;padding-left:16px;white-space:nowrap}.track-navigation button{font-size:16px;padding:10px 17px}
.track-actions{display:flex;align-items:center;gap:10px;flex-shrink:0}.download-video{display:inline-flex;align-items:center;justify-content:center;white-space:nowrap;color:var(--green);text-decoration:none}.download-video:hover{color:#174736}
.guidance{background:var(--surface);border-radius:var(--radius);padding:16px 22px 22px;margin-top:14px}.guidance h2{font-size:23px;font-weight:700;margin:0 0 18px}.steps{display:grid;grid-template-columns:1fr 1fr 1fr;gap:20px}.steps>div{display:flex;gap:17px;padding-left:18px;border-left:1px solid #d9dfe5}.steps>div:first-child{border:0;padding-left:18px}.step-number{font-size:21px;font-weight:720;line-height:1.5;color:var(--green);font-variant-numeric:tabular-nums}.steps h3{font-size:17px;line-height:1.6;margin:0 0 3px;font-weight:650}.steps p{font-size:14px;line-height:1.6;margin:0;color:var(--muted)}.preservation{text-align:center;display:flex;align-items:center;justify-content:center;gap:16px;font-size:13px;color:#87919e;margin:18px 0 0}.preservation:before,.preservation:after{content:"";width:60px;height:1px;background:#dce2e6}
dialog{width:min(640px,calc(100% - 32px));border:0;border-radius:14px;padding:24px;color:var(--ink);background:var(--surface);box-shadow:0 24px 80px #152a3b30;max-height:calc(100dvh - 40px);overflow:auto}dialog::backdrop{background:#15232bb0;backdrop-filter:blur(3px)}.dialog-head{display:flex;align-items:center;justify-content:space-between;gap:18px;margin-bottom:18px}.dialog-head h2{margin:0;font-size:24px}.dialog-head .dialog-close{font-size:30px;width:44px;height:44px;border-radius:8px;background:#f3f5f6;line-height:1}.original-intro{line-height:1.9;font-size:16px;color:#4a5562;white-space:pre-line}.original-intro p{margin:0 0 14px}.guide-note,.share-note{font-size:14px;color:var(--muted);line-height:1.8}.dialog-bottom{display:block;width:100%;margin-top:20px}#share-dialog{text-align:center;width:min(440px,calc(100% - 32px))}#share-dialog>p:first-of-type{color:#586574;font-size:16px;line-height:1.8}.qr-image{max-width:100%;display:block;margin:12px auto;image-rendering:pixelated}.lan-url{display:block;color:var(--green);font-size:16px;margin:10px 0 20px;overflow-wrap:anywhere}.share-actions{display:flex;justify-content:center;gap:12px}.toast{position:fixed;left:50%;bottom:32px;transform:translateX(-50%);background:#1f342c;color:white;padding:12px 20px;border-radius:8px;box-shadow:0 6px 20px #0002;z-index:10;font-size:15px;white-space:nowrap}
@media(min-width:1440px){.catalog{min-height:860px}.song-list{height:628px}.video-wrap{aspect-ratio:1.916}.practice-controls{margin-top:14px}.player-panel{padding-bottom:6px}.steps p{font-size:16px}.steps h3{font-size:18px}}
@media(max-width:1320px){main{padding:24px}.workspace{grid-template-columns:310px minmax(0,1fr);gap:18px}.catalog{padding:20px}.song-list{height:540px}.filter{font-size:15px;padding:11px 8px}.practice-controls{flex-wrap:wrap;justify-content:flex-start;gap:15px}.track-navigation{margin-left:auto}.loop-control{padding-left:12px}.steps{gap:14px}.steps>div,.steps>div:first-child{padding-left:12px;gap:10px}.speed-controls button{min-width:52px}.page-heading{margin-left:0;margin-right:0}.player-panel{padding:18px}.steps p{font-size:13px}}
@media(max-width:1020px){.brand-subtitle{font-size:15px;gap:16px;padding-left:16px}.brand{gap:16px}.wordmark{font-size:25px}.header-button{font-size:16px}.workspace{grid-template-columns:280px minmax(0,1fr)}.catalog{padding:18px 16px}.song{font-size:16px;gap:13px}.filter{font-size:14px}.page-heading h1{font-size:28px}.page-heading p{font-size:16px}.speed-controls{gap:6px}.speed-controls>span{font-size:14px}.speed-controls button{min-width:44px;font-size:14px}.practice-controls{gap:12px}.loop-control{border-left:0;padding-left:0}.track-navigation{padding-left:12px}.track-navigation button{font-size:14px;padding:9px 12px}.steps{grid-template-columns:1fr;gap:16px}.steps>div{border:0!important;padding-left:0!important}.guidance{padding:16px 18px}.track-header h2{font-size:26px}.track-header p{font-size:15px}}
@media(max-width:760px){.site-header{height:64px;padding:0 18px;gap:10px}.wordmark{font-size:24px;letter-spacing:0}.brand-subtitle{display:none}nav{gap:12px}.nav-divider{height:20px}.header-button{font-size:14px;font-weight:600;min-height:44px}.page-heading{display:block;margin:0 0 20px}.page-heading h1{font-size:26px;line-height:1.4}.page-heading p{font-size:14px;border:0;padding:0;margin-top:6px}main{padding:20px 14px 28px}.workspace{display:flex;flex-direction:column;gap:18px}.practice{width:100%;order:0}.catalog{order:1;width:100%;min-height:0;padding:20px 18px 12px}.player-panel{padding:16px 12px 12px}.track-header{margin-bottom:14px}.track-header h2{font-size:25px}.track-header p{font-size:14px}.favorite{font-size:14px;padding:8px 12px;min-height:42px;gap:6px}.favorite svg{width:18px}.video-wrap{border-radius:6px;aspect-ratio:16/9}.practice-controls{padding:12px 9px;margin-top:12px;gap:14px;display:grid;grid-template-columns:1fr 1fr}.speed-controls{grid-column:1/-1;display:grid;grid-template-columns:auto repeat(5,1fr);gap:5px}.speed-controls>span{font-size:12px;margin-right:0}.speed-controls button{min-width:0;padding:0 5px;height:42px;font-size:13px}.loop-control{font-size:13px;gap:9px}.switch{width:42px;height:25px}.switch:after{width:19px;height:19px}.loop-control input:checked+.switch:after{transform:translateX(17px)}.track-navigation{border-left:0;padding-left:0;margin:0;justify-content:flex-end;gap:7px}.track-navigation button{padding:9px 10px;min-height:42px;font-size:13px}.guidance{padding:16px 18px 18px;margin-top:12px}.guidance h2{font-size:20px;margin-bottom:14px}.steps{gap:14px}.steps>div{gap:14px}.step-number{font-size:18px}.steps h3{font-size:15px;margin:0}.steps p{font-size:13px}.preservation{font-size:11px;gap:9px;margin-top:16px}.preservation:before,.preservation:after{width:25px}.catalog h2{font-size:23px}.catalog-head{margin-bottom:18px}.catalog-head>span{font-size:16px}.search{margin-bottom:16px;height:48px}.search input{font-size:16px}.filters{margin-bottom:18px;gap:8px}.filter{font-size:16px;padding:10px}.song-list{height:360px;margin:0 -10px 0 -10px;padding-right:5px}.song{font-size:17px;min-height:54px;padding:12px 12px 12px 17px;gap:16px}.song-number{font-size:16px}.toast{bottom:20px;max-width:calc(100% - 32px);white-space:normal;text-align:center}}
@media(max-width:760px){.track-actions{align-items:stretch;flex-direction:column;gap:6px}.download-video,.favorite{font-size:13px;padding:7px 9px;min-height:38px}.download-video{order:2}}
.course-switch{display:flex;align-items:center;gap:9px;color:var(--muted);font-size:13px;white-space:nowrap;min-width:0}.course-switch select{color:var(--ink);background:var(--surface);border:1px solid #d6dce3;border-radius:7px;font-size:14px;min-height:42px;padding:8px 28px 8px 12px;max-width:235px;min-width:0;cursor:pointer}.filters{flex-wrap:wrap}.filter{flex:1 1 78px}.category-select{width:100%;min-width:0;height:44px;padding:0 10px;border:1px solid #d6dce3;border-radius:7px;background:#f9fafb;color:var(--ink);font-size:14px}.track-header h2{overflow-wrap:anywhere}.track-header p{overflow-wrap:anywhere}.track-header>div{min-width:0}.favorite{flex-shrink:0}body[data-course-id] .song-title{font-size:16px}body[data-course-id] .page-heading p{font-size:16px}body[data-filter-mode="hierarchy"] .filter{font-size:14px;padding:10px 8px;flex:1 1 125px}body[data-filter-mode="hierarchy"] .filter:first-child{flex-basis:100%}body[data-filter-mode="hierarchy"] .song-list{height:530px}
@media(max-width:1200px){.brand-subtitle{display:none}.course-switch select{max-width:225px}.course-switch>span{display:none}}
@media(max-width:760px){.site-header{height:auto;min-height:106px;padding:10px 18px;flex-wrap:wrap;gap:7px 10px}.site-header nav{margin-left:auto}.course-switch{order:3;width:100%;gap:12px;font-size:12px}.course-switch>span{display:inline}.course-switch select{max-width:none;flex:1;height:38px;min-height:38px;font-size:14px}body[data-course-id] .page-heading p{font-size:13px;line-height:1.7}body[data-course-id] .song-title{font-size:16px}body[data-filter-mode="hierarchy"] .filter:first-child{flex-basis:70px}body[data-filter-mode="hierarchy"] .filter{flex-basis:calc(50% - 8px)}body[data-filter-mode="hierarchy"] .song-list{height:360px}.category-select{font-size:13px}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}