.loader { border: 16px solid #f3f3f3; border-top: 16px solid #3498db; border-radius: 50%; width: 120px; height: 120px; animation: spin 2s linear infinite; position: fixed; top: 40%; left: 40%; }
        @keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }