body{font-family:Arial,sans-serif;margin:0;padding:20px;background-color:#f5f5f5}.container{max-width:1200px;margin:0 auto}.header{text-align:center;margin-bottom:20px}.header h1{color:#333;margin-bottom:10px}.header p{color:#666;margin:0}.viewer-container{background:#fff;border-radius:8px;box-shadow:0 2px 10px #0000001a;overflow:hidden;height:90vh}iframe{width:100%;height:100%;border:none;display:block}.loading{text-align:center;padding:40px;color:#666;font-size:18px}.error{text-align:center;padding:40px;color:#d32f2f;background:#ffebee;font-size:16px}.controls{padding:20px;background:#f8f9fa;border-bottom:1px solid #dee2e6}.btn{background:#007bff;color:#fff;border:none;padding:8px 16px;border-radius:4px;cursor:pointer;margin-right:10px;font-size:14px}.btn:hover{background:#0056b3}