Input
Output
<!DOCTYPE html> <html> <head> <style> .loader { border: 6px solid #f3f3f3; border-top: 6px solid #3498db; border-radius: 50%; width: 40px; height: 40px; animation: spin 1s linear infinite; margin: 50px auto; } @keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } } </style> </head> <body> <div class="loader"></div> </body> </html>