Add border at the bottom of view-changing buttons
to make those distinguishable from other highlighted buttons.
The border at the bottom makes it look like a stack of buttons that will be put into position when tapping the view-changing buttons.
Screenshots - before this change
Adwaita:dark (Phosh's default for Squeekboard)
High contrast
Default
Screenshots - after this change
Adwaita:dark (Phosh's default for Squeekboard)
High contrast
Default
Edited by MoonlightWave-12