CSS Consistency
CSSDeclaring Reusable Properties
Declaring variables is really a good shortcut, because you don't have to copy-paste the same property everywhere - just put the variable in a place you want and you only have to change the value one time to make changes to all elements that have this variable:
You can declare anything for a variable. You can of course make variables and reuse them infinitely.
Dynamic Theme Switching with Variables
You can also redeclare these variables, as this example shows below: