Configure panel layout and page margins

[danbraunai]

Currently, the panel sits within the same margins as the text. But we can make the panels much wider than that, as they do in most interactive diagrams in distill articles

[danbraunai]

Done for the first two panel instances that have one row in 69cf167 using the distill class "l-page". The next two panel instances take up too much vertical space when using this (or the smaller "l-body-outset") classes.

I think we may want the panel controls to the side of the 4 plots in the second two panel instances. As it is now, I can't see the whole panel when using my laptop. Updating the issue name

[NixGD]

Part of this may also involve playing around with the layout of the panel itself. For instance, it could be nice to have the website choose whether the panels are all in a row or in a 2x2 grid based on the width of the browser. It would be pretty easy to do this at startup. Somewhat harder (but possible) to do it reactively to browser resizing.

[danbraunai]

True, that could be cool. I had more of a play around trying to get the scatterplot and the barchart to not appear so small when the controls are on the side instead of the top. But I couldn't figure it out for now. I will leave this (for one of us) for later.