where do i change the css of the contact form widget?

hi

i purchase your contact widget,
here is a link to the site:

http://mytzunaeat.co.il/

1. in the home page' the first menue from the right side' there is a double line next to the right side of the widget, how should i get rid of?
2. there is a horizontal scralling in the widget, how do i get rid of that?

please do not send me to "history of some other people question, that may conect to my question.
my englisg is not my first language, and to go true long protocol of text it will waiste hough of my day. i want please a answere in detail and clear how much that you can.

thank you. iris