Issue with the "items number" and "add to cart button"

Problem: 

The "items number" and "add to cart button" are very near each other and the "items Number " is too wide compared to what it is in initial theme: 

Solution: 

If you encounter this error, please go to admin -> MGS -> Front-end Builder -> Font & Style -> Custom Style: 

And replace this paragraph:

.catalog-product-view .product-info-main .box-tocart .fieldset .product-addto-links+.field.qty

{ width: calc(100% - 63px) !important; margin: 0; }

To this paragraph:

 @media(max-width: 767px) { 

.catalog-product-view .product-info-main .box-tocart .fieldset .product-addto-links+.field.qty

{ width: calc(100% - 63px) !important; margin: 0; }

}

Finally,  clear all cache and check your site on private browser: