Hyperlink not displaying as link (blue/underlined)

Hi – I have the Newslite theme (free version) and I really like it. I have a pretty simple blog, and it serves my purposes nicely. I have one issue though: when I create a post in the Bluehost/Wordpress editor, any links I create show up ‘properly’: they are blue and underlined. However, when I publish the post, the formatting disappears and the link is basically invisible in regular black in. If you hover over it with the mouse, it does turn blue, but only in the full post, not in the preview.

I’ve searched for solutions to this and for a few other themes the publisher has offered bits of code to insert under the CSS tab. I’ve tried a few of these, but it has not produced the desired result. Can you help? Thanks, Caroline