I am trying to customize a posterous theme. Using their help guide but don't know how to CSS the {blocks}. For example: I want to change the font color of posts?
You can try something like this if you're using a custom posterous theme:
.post-list li .details h2 a{color:#F15a24; font-family: Arial, Helvetica, Sans-serif; font-size: 16px; font-style: Bold;}
.post-list li .details p {color:#2b241c; font-size: 12px;}
.post-list li .details .date a{color: Color: #83881b; font-size:12px; font-family: Arial, Helvetica, Sans-serif;}
.post-title h2 a{font-family: Arial, Helvetica, Sans-serif; font-size: 12px;}
.post-list li .details h2 a{color:#F15a24; font-family: Arial, Helvetica, Sans-serif; font-size: 16px; font-style: Bold;}
.post-list li .details p {color:#2b241c; font-size: 12px;}
.post-list li .details .date a{color: Color: #83881b; font-size:12px; font-family: Arial, Helvetica, Sans-serif;}
.post-title h2 a{font-family: Arial, Helvetica, Sans-serif; font-size: 12px;}