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@media(max-width:540px){:root{--sidebar:0px}.sidebar{inset:auto 0 0;width:100%;height:62px;padding:0;background:#16232cf5;border-right:0;border-top:1px solid #304858;backdrop-filter:blur(12px)}.sidebar .brand,.sidebar-bottom{display:none}.sidebar nav{display:flex;margin:0;padding:5px 12px;gap:10px}.nav{margin:0;font-size:9px;padding:6px;gap:2px;flex-direction:column;border-radius:7px;line-height:1.5}.nav i svg{height:18px;width:18px}.main{padding-bottom:62px}.topbar{height:59px;margin:0 17px}.page{padding:25px 16px 10px}.page-heading{gap:4px;margin-bottom:20px}.page-heading h1{font-size:21px}.page-heading p{font-size:10px;max-width:240px}.eyebrow{font-size:7px;letter-spacing:1.5px}.heading-actions{gap:5px}.video-stage{min-height:235px}.video-empty{padding:20px 7px}.empty-art{transform:scale(.8);height:95px;margin-bottom:8px}.video-empty h2{font-size:16px}.video-empty p{font-size:10px}.video-empty small{font-size:8px}.video-empty .button{font-size:10px;min-height:32px;padding:5px 12px}.stage-top{top:10px;left:10px;right:10px}.stage-tag{font-size:8px}.subtitle-area{padding:10px 12px;height:100px}.english{font-size:17px}.english.muted{font-size:12px}.chinese{font-size:10px}.player-dock{padding:12px}.transport{gap:0;grid-template-columns:auto 1fr auto}.playback-buttons{gap:1px}.play-button{width:37px;height:37px}.subtitle-toggles .icon-button{display:none}.subtitle-toggles{gap:0}.text-toggle{min-width:22px;font-size:9px;padding:0 3px}.audio-controls input,.audio-controls .icon-button{display:none}.audio-controls select{font-size:9px;padding:3px}.icon-button{width:28px}.loop-expand{font-size:8px;padding:0 2px}.under-player{font-size:8px}.learning-note{font-size:8px;align-items:flex-start}.version-label{display:none}.app-footer{margin:15px 16px 0;font-size:8px}.account-hero{padding:18px;gap:12px;flex-wrap:wrap}.account-hero h2{font-size:16px}.account-hero p{font-size:10px}.account-hero .button{font-size:10px;min-height:30px;padding:6px 10px}.redeem-row{padding:13px;flex-wrap:wrap}.redeem-row label{width:100%}.dialog-content{padding:30px 24px}.dialog-content h2{font-size:21px}.dialog-content>p{font-size:11px}.saved-card-actions{flex-direction:column}.toast{left:50%;bottom:80px}.selection-button{bottom:115px;left:35%}.section-toolbar>.search{width:100%}.filter-group button{font-size:10px;padding:6px 10px}}
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