H1, H2 & H3 Tags Unformated on Blog Post

Hi,

I used the following custom css to add margins to my blog posts page but the h1, h2, h3, etc headers don’t follow the margin and are off on the page. Is there a way to get them aligned with the paragraphs in the blog.

Here is the custom css I used, and the blog post in reference: http://foodvendingprofits.com/how-to-start-a-mobile-food-business/

/* Single */

article.post .entry-header h1.entry-title, article.page .entry-header h1.entry-title {
text-align: center;
}

article.post .entry-header .entry-meta, article.page .entry-header .entry-meta {
text-align: center;
}

.single .entry-content p {
margin-right: auto;
margin-left: auto;
max-width: 650px;
}