.lesson{max-width:1040px;margin:auto;padding:28px 20px;color:#264d46}.lesson p,.lesson li{line-height:1.65}.lesson img{max-width:100%;height:auto}.lesson .notice{padding:20px;background:#eee4d1;border-radius:10px}.lesson .downloads{display:flex;gap:14px;flex-wrap:wrap;margin:25px 0}.lesson .downloads a,.lesson button{border:1px solid #53766c;padding:12px;border-radius:7px;background:#fff;color:#264d46}.lesson details{border:1px solid #c6d4cf;border-radius:8px;padding:18px;margin:12px 0}.lesson summary{cursor:pointer;font-weight:bold}.lesson pre{white-space:pre-wrap;overflow-wrap:anywhere;font:16px/1.6 system-ui}.lesson iframe{width:100%;aspect-ratio:16/9;border:0}.lesson .languages{display:flex;gap:18px;flex-wrap:wrap}.lesson a{color:#275c50}