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<html><head><style> #myDIV { width: 300px; height: 200px; border: 1px solid black; background-image: url('w3css.gif'); background-size: 20px 20px; animation: mymove 5s infinite;}@keyframes mymove { 50% {background-size: 125px 125px;}}</style></head><body><h1>Animation of background-size</h1><p>Gradually change the background-size from "10px 10px" to "125px 125px", and back:<p><div id="myDIV"></div></body></html>