CSS for margin

Hello
Love you plugin.

but when placing it in WPOcean template its to wide.
My builder is Divi…that I use.

When placing the shortcode into divi on the page the search field has
a strange look..its a square around the search text and the icon …to the right with out
anything.

When placing the short code to WPOcean theme the searchfield is full screen with
Dose someone have a scc for the widh of the search field so I can place it to center of the page with 600px widh.

thank you all for the help