CSS box-sizing Property
The box-sizing property in CSS specifies how the user should calculate the total width and height of an element, including whether or not padding and borders are to be included.
|content-box||Default. Only the content is included in the width and height properties (as well as the min/max values). Padding and a border are not included.|
|border-box||The width and height properties (as well as the min/max values) include content, padding, and a border.|
|initial||This property is set to its default value.|
|inherit||This property is inherited from its parent element.|
|Element||Chrome||Firefox||Safari||Edge / IE||Opera|