Then you need to take the Marzipano index.html and edit the "<div id="pano"></div>" line, so it stay only with "<div id="pano">", so you then put the removed "</div>" below the last "</script>" found (that one I've listed above).
After doing this, the division id=pano embraces all panorama elements, so their absolute sizes and positions will be relative to the pano div and you can change only it. So, at the style.css you can start doing other things.
If you change the:
#pano {
position: absolute;
top: 0;
left: 0;
width: 100%;
height: 100%;
overflow: hidden;
}
below, the changed lines:
top: 200px;
left: 300px;
width: 700px;
height: 400px;
Then we can notice that all elements of the panorama rectangle (controls, title bar, full screen button, etc) will vanish, because they stay below the panorama itself. So we would need to put the panorama to a lower Z level or increase other element levels. I did this by using "z-index: 1;" in each element. Then I've tried to make a common page so the panorama would be inserted on it. Another problem rises: the CSS code of Marzipano changes many elements. A common header "<h1>" wouldn't be big or have black font. Here is the page status when I've given up:

The "Marzipano framed test" is a "header 1" element, but is with the same font size as the following text. All text is white, which I didn't wish. It all shows that the pages are mixed up, the marzipano CSS code influences the page code and vice versa. To do the thing well done it would be necessary to guarantee IDs, classes and styles names distinct between your page and marzipano, so each style configuration don't change the other one.
Well, I won't continue with the job... I would use "iframe" and be happy :)
Bests,