Point one style class to another?

You can use selector grouping:

.foo, .list1 li { 
  background-color: red; 
} 

No. The best you can do with "native CSS" is to use a multiple selector:

.foo, .list1 li {
   ...
}

Otherwise there are preprocessors that can help with this such as SASS.

Not with any syntax like that (and don't confuse a "class" (an HTML term) with a "class selector" or a "rule-set").

Your options are multiple classes, grouping selectors or preprocessing.

You might want to look into a CSS preprocessor such as SASS or LESS. You can define variables that can be used throughout your code. It greatly speeds up your coding when you're familiar with it.

http://sass-lang.com/

http://lesscss.org/

Using SASS:

$darkred : #841c14;
.box { 
    background: $darkred;
}