CSS value as mathematical expression

Question

Is there anyway that I can write a css value as mathematical expression? Example:

div{
    height: 50% + 30px;
    width: 40em - 5px;
   }

If t

Answer 1

You can not do this with CSS, but you could (and much more) with a CSS preprocessor, like LESS, SASS or my favorite Stylus. THe final output is plain old CSS, but it must be compiled first.