Código
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <style> .zoom { display: block; height: 60px; width: 468px; margin-left: auto; margin-right: auto; animation-name: zoom; animation-duration:5s; } @keyframes zoom { 0% { height: 0px; width: 0px; } 100% { height: 60px; width: 468px; } } </style> </head> <body> <div> <img class="zoom" src="https://media.giphy.com/media/l41lLf17l7YCZ4Tjq/giphy.gif"> </div> </body> </html>