Mobile UI tweaks

[kaushik12]

Final check of mobile UI after below changes affected it

• Header seems too big
• Starting station select text box overlaps with first station in the dropdown making it hard to select
• date-range text in the footer too big and overflows
• additional padding needed between slider and by stops chart
• If possible About and Feedback modal made 100% width only on mobile
• Data Clinic and Contribute sections look bad on small screens
• Methodology png seems to shrink a lot on smaller screens

[kaushik12]

@stuartlynn Added some of the issues I noticed when playing around on my phone.

[stuartlynn]

Have tweaked everything apart from the methodology png. It should be 100% width on mobile but I think there is a limited width in general on mobile screens.

If you have another png that would be more suitable for mobile screens we can have one that displays on mobile and one that displays on desktop.

With the new 100% width modals on mobile, this might not be quite as big an issue.