fix: prevent content from reaching upper and lower border in print

[bard]

Thanks for sharing this nice template.

I found that, on CVs longer than one page, content would sometimes hit the top and bottom border when printing or exporting as PDF. This PR adds top and bottom margins. (See before/after screenshots below.)

Additionally, since the margins would cover the right column's background, just for the print version I removed the background and added a thin separation line between the columns. This may be a less welcome change if you'd like to keep the web and print version very similar.

Without margins:

With margins:

[ineesalmeida]

Thanks for the contribution! This doesn't work if one wants to keep the right column colored and full height (which was what I was going for when I wrote it). This was initially a one page CV template, but I did forget to add those margins when adding the multiple page option.

I think this either becomes optional with a parameter in config, or I need to find another way to add the margins.