... Firefox, the property uses the -moz- prefix—that is, the property is -moz-box-sizing; and in WebKit, it has the -webkit- prefix, so it would be -webkit-box-sizing. Rather than obfuscate the ... is the total width of the content, the padding, and the border—in other words, the entire box (without the margin). To illustrate this, let’s return to the previous example code and add the ... width—150px—is the width of the content, and the border and padding are added to the content. In the second example, the value is border-box, meaning the 150px width includes the border and padding,...