body{font-family:Arial,Helvetica,sans-serif;background:#111;color:#eee;margin:0;padding:0;overflow-y:hidden}.container{max-width:1000px;margin:0 auto}.preview{height:540px;background:#222;border-radius:8px;display:flex;align-items:center;justify-content:center;overflow:hidden}.preview img{max-width:100%;max-height:100%;object-fit:contain}.filmstrip{display:flex;gap:10px;overflow:auto;padding:12px 0}.thumb{width:140px;height:90px;object-fit:cover;border-radius:6px;cursor:pointer;flex:0 0 auto;border:3px solid transparent}.thumb.selected{border-color:#1db954}h1{margin:0 0 12px}