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<html><head><style> #myDIV { inline-size: 70%; block-size: 200px; box-sizing: border-box; border-block: 1px solid black; background-color: lightgreen; animation: mymove 5s infinite;}@keyframes mymove { 50% {border-block: 15px solid orange;}}</style></head><body><h1>Animation of border-block</h1><p>Gradually change the border-block property:<p><div id="myDIV"></div><p>The border-block property is a shorthand property for all border-block properties.</p><p>See individual border-block properties to see which is <em>animatable</em>.</p></body></html>