How do I make the paragraph text wider?

[omfaonline]

Hello. This might be a very silly question, but bear with me:
My blog text paragraphs are very narrow. I've used the firefox web developer tool and found out it was 400px wide:
http://mrjinglemeister.tumblr.com/

I want to make it 500px wide. I've searched in the tumblr html as well as all 3 css files for a way to do it, to no avail. Help?

[abduraooft]

You have

.post .content {
    font-size: 13px;
    line-height: 1.538;
    margin-bottom: 20px;
    padding-right: 100px;
}

in http://static.tumblr.com/iqfzjqj/NOSlbvgqu/screen.css

Remove that right padding.

PS: Don't you have firebug?

[omfaonline]

@abduraooft

Thank you so much! I'll download firebug, it looks great