In order to make the compass sliders easier to use on desktop and mobile web, we should increase size of the clickable areas for the sliders. - [ ] Increase the vertical height of the clickable area for the slider bars. - [ ] Make the slider labels clickable (and behave as if the user clicked on the extreme ends of the slider bar). - [ ] Use `cursor: pointer;` style for all clickable areas.  Magenta and yellow overlays intended to visualize clickable areas -- not visual implementation.