Non-constant and immutable state variables don't differentiate visually

[RomiRand]

Currently you need to scroll up and check if a variable is immutable or not when evaluating storage accesses for gas optimizations which can be a bit annoying. That's especially true for bigger contracts with many state variables. From a gas cost perspective it would make more sense to use the green border color of constant state variables instead of the golden color of non-constant state variables. Optimally there should be a separate border color for immutables so you can immediately differentiate all the storage types from each other.