body{margin:0;font-family:-apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;background:#f9f9f9;color:#333}header,footer{text-align:center;padding:1rem;background:#222;color:#eee}h1{margin:0;font-weight:600}main{display:flex;flex-direction:row;min-height:80vh;max-width:1000px;margin:2rem auto;background:#fff;border-radius:8px;box-shadow:0 2px 8px rgba(0,0,0,0.1)}.gallery-list{flex:1;padding:1rem;border-right:1px solid #ddd;overflow-y:auto}.gallery-list ul{list-style:none;padding:0;margin:0} .gallery-list li{margin-bottom:0.75rem}.gallery-list button{width:100%;padding:0.5rem 1rem;border:none;background:#007acc;color:#fff;border-radius:4px;cursor:pointer;font-size:1rem;transition:background-color 0.3s ease} .gallery-list button:hover, .gallery-list button:focus{background:#005fa3;outline:none}.gallery-frame{flex:2;display:flex;justify-content:center;align-items:center;padding:0;overflow:hidden;border-radius:0 8px 8px 0}iframe{width:100%;height:100%;border:none;border-radius:0 8px 8px 0}footer p{margin:0;font-size:0.875rem} @media(max-width: 700px){main{flex-direction:column} .gallery-list{border-right:none;border-bottom:1px solid #ddd} .gallery-frame{border-radius:0 0 8px 8px;height:300px}}