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<html><head><style>div.ex1 { width: 300px; background-color: yellow;}div.ex2 { width: 300px; padding: 25px; box-sizing: border-box; background-color: lightblue;}</style></head><body><h2>Padding and element width - with box-sizing</h2><div class="ex1">This div is 300px wide.</div><br><div class="ex2">The width of this div remains at 300px, in spite of the 50px of total left and right padding, because of the box-sizing: border-box property.</div></body></html>