Yes. That sounds like the browser default. Okay, so this a two step deal.
1) You need to give your row a unique CSS class. You'll do this by selecting Row > Edit (pencil) and then finding the "Row CSS Class." Type a name in that field (I named my row "green-row" for purposes of this example.)
2) Go back to your text card. Switch into the HTML editor. You can take off the inline styles I gave you earlier as this you won't need them with this snippet. Then at the top of your text card, you'll want to add:
<style>
.green-row a:link {color:#000000; font-weight:bold;}
.green-row a:hover {color:#000000; font-weight:bold;}
.green-row a:visited {color:#000000; font-weight:bold;}
</style>
But replace .green-row with .your-class-name instead.
This will ensure that you have black, bold text for all three link states: link, hover, visited. But if you don't put the class name of the row ahead of those selectors, you're going to get that style for every link you have on your site and that might not benefit you if any of your other rows have dark backgrounds. Generally, we want to avoid really generic selectors for that reason - they are far more likely to have unpredictable reach, so I definitely recommend making sure you have a unique row class around generic selectors to avoid that situation.
