*{box-sizing:border-box}html,body{margin:0;min-height:100%;background:#081525;color:#eaf4ff;font-family:Arial,Helvetica,sans-serif}.lesson{max-width:1050px;margin:20px auto;padding:22px;background:#10233a;border:1px solid #25465f;border-radius:18px}h1{margin:8px 0;text-align:center;font-size:30px}.subtitle{text-align:center;color:#bfd6e6;line-height:1.5}.progress{display:flex;justify-content:space-between;gap:15px;margin:20px 0 12px;font-weight:bold;color:#f6d28b;flex-wrap:wrap}.scene{background:#091a2d;border:1px solid #35546c;border-radius:14px;overflow:hidden}svg{display:block;width:100%;height:auto}.mediumLabel{font:bold 27px Arial,Helvetica,sans-serif;fill:#edf7ff}.mediumLabel.dark{fill:#173a4a}.normalLabel{font:21px Arial,Helvetica,sans-serif;fill:#e6dfff}.controls{display:flex;flex-wrap:wrap;gap:10px;margin:18px 0}button{padding:12px 19px;border:0;border-radius:9px;background:#19b7ca;color:#061827;font-size:15px;font-weight:bold;cursor:pointer}button.secondary{background:#28455e;color:#edf8ff}button.audioButton{background:#e4b55c;color:#142337}button:disabled{opacity:.35;cursor:not-allowed}.readout{display:flex;flex-wrap:wrap;gap:12px}.readout span{flex:1;min-width:210px;background:#172e47;padding:15px;border-radius:9px}.readout strong{color:#ffd36c;margin-left:8px}.explanation{margin-top:15px;padding:17px;background:#172e47;border-left:4px solid #19b7ca;border-radius:8px}.explanation h2{margin:0 0 8px;font-size:20px;color:#fff}.explanation p{margin:0;line-height:1.6;color:#d3e7f4}.audioStatus{min-height:18px;margin:10px 2px 0;color:#c1d7e8;font-size:13px}@media(max-width:600px){.lesson{margin:0;padding:12px;border-radius:0}h1{font-size:24px}button{flex:1}}