I have a button as part of the content of an html file - > this one in turn within an iframe - > the iframe in turn within the mother website.
How can I indicate with jquery the button that makes the mother page that contains everything scroll up with animation and speed fast ?
You must access the parent window object using window.parent . The object window general does not have a parent, only have the iframes, object or the obsolete, frame. From there select the body to animate it:
$(window.parent.document.body).animate({ scrollTop: 0 }, 'fast');