Footer appears only on Mac

Site URL: https://share.squarespace.com/L1u99gWx

Hi all,

I am having trouble editing my landing page - basically I just want an image with no header/footer but then want header on site pages...

I added a code I found online (below) and it removed the header & footer however they still appear on Mac books only (not Windows based products)

<style>
.header, #footer-sections {
display:none !important;
}
</style>

Can anyone help or advise what I can do to fix this or tell me how to just have a header on site pages but not opening home/landing page?

Thank you.

You mean a gap in bottom? Can you share link to your site?