Button not styled well on campaigns detail view page

My version is 7.6.4. I use Suite 7 theme. When i look at campaigns detail view page, In Email Marketing sub panel the create button is not styled well.
Can i correct this?

I am running 7.6.4 and the style is correct (see image).

Have you tried:
. clearing your browser cache
. running a quick repair and rebuild
. setting permissions correctly

Possibly the problem you are experiencing is due to one of those things.

I think you are using Suite R theme. I did every things which you are mentioned but no result. The other sub panels are good. Only this panel has a issue.

I m using these permissions;

sudo chown -R www-data:www-data .
sudo chmod -R 755 .
sudo chmod -R 775 cache custom modules themes data upload config_override.php

You are right the picture I took is with the Suite R Theme.

So I tested the Suite 7 Theme and it is still correctly styled:

I can suggest you a few more things (although I doubt that they will work):

. switch to another theme, then back. In between log out, close browser, clear browser cache, re run permissions reset as well as Quick Repair and Rebuild
. try with different browser
. try with a different user

I did every things, but no result. Do you know which file to look at the code?