:root{--navy:#17334d;--blue:#355c7e;--red:#b6484b;--ink:#20354a;--muted:#718091;--line:#dce3e9;--pale:#f1f5f8;--paper:#fff;--green:#28755e;--max:1300px}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:#f7f8fa;color:var(--ink);font-family:"Segoe UI","Microsoft YaHei",Arial,sans-serif;font-size:16px;line-height:1.8}button,input,select{font:inherit}a{color:inherit;text-decoration:none}button,a,input{touch-action:manipulation}button{cursor:pointer}button:disabled{cursor:default;opacity:.45}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible,summary:focus-visible{outline:3px solid #7597bc;outline-offset:4px}button{color:var(--ink)}.skip{position:fixed;left:20px;top:-80px;background:white;padding:10px;z-index:100}.skip:focus{top:10px}.topbar{height:84px;background:#ffffffed;border-bottom:1px solid var(--line);display:flex;align-items:center;gap:38px;padding:0 max(32px,calc((100vw - 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.audio-lesson{background:#f0f4f7;padding:25px;border:1px solid #dde5ed}.audio-lesson audio{width:100%;display:block}.audio-lesson p{text-align:center;margin:10px 0 0;font-size:12px}