De-crampify the mobile UI

[gregdan3]

A lot of people seem to be using ilo Muni on mobile, but frankly, its mobile UI is dogwater.

• The graph should be able to be taller, and probably wider
• (Set negative margin for it? Just a little bit?)
• The article should either fit to the screen or to content, whichever comes last (I do this trick on my dev site, gregdan3.dev)
• (Getting more complex) Move the Y axis info entirely to the legend while on mobile

[gregdan3]

Another suggestion from @KelseyHigham: Make the search bar take the width of the page on small portrait displays. Good choice, but makes #4, #10, and #11 harder.