[Theme Horse Support Team]

Hi Mravi,

To change the background color of page/post container just login to your WP dashboard/admin and go to Appearance > Customize > Additional CSS and paste below custom CSS code:

.post, .hentry,
.product.type-product,
.type-attachment {
    background-color: #ffffff;
}

Note: Change above Hex background color code #ffffff to your own Hex color code.

Thank you!