You can edit Content Box for styling the box and then edit the Contact Form 7 Pro element for styling the form.
For editing the form fields, you can go to Dashboard > Contact
This element has -100px margin from bottom, you can find and modify it in Element Edit > Styling Tab > Container Stylekit
Instead Quick Contact also you can create any page and assign it.
You can find the Popup Modal Box element under this button in Page Builder and click on #guestbook_popup and it will open and then you can edit it and add or remove content of modal box.
This Popup Modal Box had unique id (guestbook_popup) and you should set button links to this id with # character like this: #guestbook_popup
In widgets find Footer 1 sidebar and edit it.
For changing background of Footer, Go to Theme Options > Footer > Footer Widgets > Container Style Kit