message: Renames to `--fill` for consistency; implements disabled state
diff: &:hover
  background-color colors-gray-secondary
  - &--block
  + &:disabled
  + &:hover
  + background-color colors-gray-background
  +
  + &[disabled]
  + &:after
  + display none
  +
  + &--fill
  display block
  > select
  