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<html><head><style> .div1 { width: 300px; height: 100px; border: 1px solid blue; box-sizing: border-box;}.div2 { width: 300px; height: 100px; padding: 50px; border: 1px solid red; box-sizing: border-box;}</style></head><body><h1>With box-sizing</h1><div class="div1">Both divs are the same size now!</div><br><div class="div2">Hooray!</div></body></html>