Box Sizing

The box-sizing property determines if padding and border should be added to the value set for width/height or form part of the value set for width/height (including min/max). Although the default value for box-sizing is content-box, many view this to be a mistake as elements can be easier to layout when padding and border are included in the width (border-box).

Value Description
content-boxPadding and border values are added to the value given for width/height. For instance, total width = width + padding + border. This is the default.
border-boxPadding and border values form part of the value given for width/height. For instance, total width = width.

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