The Styles Configuration dialog uses standard CSS syntax.
Some ideas:
If you would like borders removed try using border:0px.
If you would like the heading background to be a different color then edit the th row.
You could try something outlandish (ok - hideous) like:
border:1px solid Green;background-color: #FF0000; text-align: right; color: cyan;
There are plenty of pages on the internet with details for CSS. One I have used is:
http://www.w3schools.com/css/css_table.asp
and
http://www.w3schools.com/css/tryit.asp?filename=trycss_table_fancy
You can mimic their table format with:
th | font-size: 1.1em; text-align: left; padding-top: 5px; padding-bottom: 4px; background-color: #A7C942; color: #ffffff; |
td | font-size: 1em; border: 1px solid #98bf21; padding: 3px 7px 2px 7px; |
tbody tr:nth-child(even) | color: #000000;background-color: #EAF2D3 |
When you have finished click Save. You can see a sample table on the Doctoolkit Configuration page.