*{box-sizing:border-box}body{margin:0;background:#edf4f7;color:#203e50;font:16px/1.5 Arial,sans-serif}header{display:flex;align-items:center;justify-content:space-between;gap:20px;max-width:1300px;margin:auto;padding:20px}header img{width:300px;max-width:100%;height:auto}a{color:#007a8a}main{max-width:1300px;margin:0 auto 24px;background:white;padding:24px;border-radius:12px}h1{font-size:28px;color:#123854;margin:0 0 10px}h2{font-size:20px;margin:0 0 12px}.intro{color:#486171;margin:0 0 20px}.layout{display:grid;grid-template-columns:280px minmax(0,1fr);gap:24px}#lessons{max-height:760px;overflow:auto;padding:2px 10px 2px 2px}#lessons button{display:block;width:100%;padding:12px;margin:0 0 7px;text-align:left;background:#edf4f7;color:#203e50;border:1px solid #d5e3eb;border-radius:7px;font:14px/1.4 Arial;cursor:pointer}#lessons button[aria-current=true]{background:#123854;color:white}.controls{display:flex;flex-wrap:wrap;gap:8px}button:focus-visible,a:focus-visible{outline:3px solid #007a8a;outline-offset:2px}.controls button{padding:10px 16px;border:0;border-radius:6px;background:#123854;color:white;font:700 14px Arial;cursor:pointer}.controls button:disabled{opacity:.5;cursor:default}#status{font-size:14px;min-height:21px}#media{width:100%;background:#f4f8fa;min-height:260px;border:1px solid #d5e3eb;border-radius:8px;overflow:hidden}#media ruffle-player{display:block;width:100%;height:auto;aspect-ratio:892/736}#media iframe{display:block;border:0;width:100%;height:640px}@media(max-width:700px){header{padding:16px;flex-wrap:wrap}header img{width:250px}main{padding:16px;border-radius:0}h1{font-size:23px}.layout{grid-template-columns:1fr;gap:18px}#lessons{max-height:200px}#media{min-height:180px}#media iframe{height:480px}}

#media video{display:block;width:100%;max-height:740px;background:#111}