Hi friedrichsantana,

You will need to go to the Custom CSS area, then search and remove these CSS lines (they are separated and can be located from the top to the bottom so search them one by one):

/* Shop - Sale Button Styling */
.woocommerce .product .item-images {
    background:  #EEE;    
}
/* Shop - Catalog Image Width */
.woocommerce .product .item-images  {
    background: #EEE;
}
/* Shop - Single Item Image */
.single-product .images {
    background: #EEE;
}
.woocommerce .single-product .kalium-woocommerce-product-gallery .main-product-images.carousel .woocommerce-product-gallery__image {
    background: #EEE;    
}