Full-height control panel

[Karinon]

I am a bit unhappy with the current control panel. It does not take the full height of the window and has to be positioned via position: fixed. My problem with this is that I put a lot of effort into aligning the camera so that the Earth projection is visible in the center of the remaining area between the control panel and the right edge (this is particularly important for smaller laptop screens or Freva's iframe). This makes the camera code much more complicated and would be completely unnecessary if the panel had not been placed with position: fixed but was a normal HTML element.

Since more features are likely to follow anyway and we will sooner or later reach the edge of the window, I think we could drag the panel to the full height of the window and simplify the camera code again.

In the course of this, it would also make sense to introduce subheadings for the panel's functions. I understand that there is a certain elegance in it being so clear, but I think that is just our personal bias and that it is not as obvious to every user as it is to us.

[d70-t]

Yes, having the controls a regular HTML elements should be the cleaner way of handling this. We should however also have an eye on how it renders on a Phone (which I guess will also be easier when using a regular HTML element).