Centering internal pages

how can I center the content on this page to align in the middle of the white?

is there a css code that will automatically center align the content of my internal pages? (excluding the blog)


Here is the CSS code to centering content of the page:

.page-id-554 .content-area.col-md-9 {
    width: 100%;
    text-align: center;

You can use Custom CSS plugin to add the code in above to your site.