OK like Brad suggested, If you are running the SMF 2.0 + the index.css is where you'd edit the styles, ( look and schemes ) The Front page, using TP should inherit the same themes setting, unless you selected another theme when you set up your Front page and if did set to another Theme for an article, you made go to TP > Submissions > select the edit and go to the bottom of the page that"s opens and elect the theme you want to utilize for this page!
Note: that you will then need to Tweak the index.css for that theme you selected for this page or article.
In order to edit the them u are using at present go the Admin > current theme > click on "Modify the stylesheets. (colors, fonts, etc.)" a set of windows will open the bottom window, you may edit the index.css code as needed!
This post id to benefit the general users..just in case LOL!
If you need help editing the TP styles, please let me know, but don't think they are related to this request!/?