How do I add borders to the form fields in the checkout page of my BC shop?

I am setting up my Shop for my website www.myartscreative.com. So far, so good. I am testing out going through the steps of ordering a copy of my sketch book, adding the appropriate shipping, etc. However, I notice when testing the checkout page, most of the fields do not have a border around them which makes it hard to see where to  fill in the pertinent info. How do I add a border or fill (or both) the form fields so my customer can easily see where to type in their information?  Here is the link to my shop's "check out page".