how to edit page heading size in twenty twelve theme

Hi there ,

I have looked over and tried a few things and have not found a solution to this

I want to change the page title size as i have already changed my post page by using this code:

.entry-title a:link, .entry-title a:visited {
color: #000000;
font-size: 1.6em;
text-decoration: bold;
}

This works fine for the posts but I have tried a few things which selector do i edit>?

this is my site so far

thanks