Use a class name in CSS like a variable

Question

Is there any possibility of using the name (or part) of a CSS class CSS like a variable?

For instance:

.width-NUMBER {
   width: NUMBERpx;
}

Then in my HTML I might look like:

<div class = "width-100">
Hello
</div>
<div class = "width-50">
bye
</div>