Wordpress Page Builder is mixing up with theme - why?

I am new to Wordpress but not HTML and CSS. I installed a theme and then got the Page Builder Plugin.

When I use the page builder it seems to want to create a lovely crips full width site but it goes over the the top of some of the theme style/content.

It's mixed up.

How do I get page builder to be the only source for the overall design.

I considered using CSS to hide some elements of the theme and have managed to hide the side bar - is this the best practice?

Please see the linkhttp://ift.tt/1Q8ZTNz

If it is a case of just using CSS to hide certain elements then great! But I am thinking there is a simpler way as it is in Wordpress.

via Chebli Mohamed