Hi @abhisheksharma8789,
You can add the below CSS to your site from Appearance > Customize > Additional CSS:
.home.blog .site-header, .home.page:not(.page-template-template-homepage) .site-header, .home.post-type-archive-product .site-header{
margin-bottom: 0 !important;
}
Let us know how it goes!
Hi there @abhisheksharma8789
You can try the CSS below:
@media screen and ( max-width: 768px ) {
.home header#masthead{
margin-bottom:0 !important;
}
}
This will only work on mobile.
I hope this helps!
Hi there @abhisheksharma8789
As I see, the CSS syntax on your site isn’t correct:

The extra @media screen and (max-width: 768px) { needs to be eliminated.
I’d also suggest validating your CSS with a tool like https://www.cssportal.com/css-validator/
I hope this helps!
I have removed it but not worked
Hi there again!
I see there is an unwanted character in your CSS:

You can remove that and validate your CSS with https://www.cssportal.com/css-validator/
I hope this helps!
Rynald0s
(@rynald0s)
Automattic Happiness Engineer
Hi @abhisheksharma8789
I’m glad we were able to help! If you have a few minutes, we’d love if you could leave us a review:
https://wordpress.org/support/theme/storefront/reviews/#new-post
Cheers!