Dear Leslye,
I’ve finally managed to solve the loading issue: instead of using Javascript for defining the width and margins, I’ve entirely rewritten the code to use PHP (which loads before JS) to generate a series of CSS @media queries which now govern the width of the website on all possible screen sizes. I’ve inserted the code on your website already, please have a look and let me know if it does what you needed.
Sincerely,
Andrew / Satori Studio