CSS-border, margin, padding-Browser

 

In border, margin, and padding, when different browsers parse, the value of heigh is always different.

Border, after the W3C HTML 4.0.1 standard is used, it is not in the height, that is, Your Height = height. Otherwise, IE6, 7, and 8 contain Height = height-Up and down border, but FF does not.
Padding is not counted in height after W3C HTML 4.0.1 standard is used, that is, Your Height = height. Otherwise, in IE6, 7, and 8, heigh = height-Upper and Lower padding, but FF does not.
Margin, whether or not the W3C HTML 4.0.1 standard is used, is not included in the height, that is, Your Height = height. But in actual height measurement, the upper and lower margin values are subtracted. This is normal because it is margin.

 

Therefore, you must use doctype. Otherwise, it will be very troublesome to handle the differences between browsers. We recommend that you use an adaptive height.