How to change the font size and color of page headings.

Hello sir,
Please help me and guide How to change the font size and color of page headings. i have got the option in CSS file and got follwing code
.post-titles a{
text-decoration:none;
font-family:oswaldbook;
font-size:26px;
color:#dd3333;
line-height:1.3em;
i tried to edit this but it changes the heading font of only posts but i am looking help to change the font size and color of pages. Also how to control the headings color of widgets.
please help. highly obliged and thanks in anticipation.