Hello,
I have test your site and it seems due to your custom code or some third party plugin all the labels become transparent and did not clearly seen.
To fix this you need to remove your custom code or if you are using child version of theme then switch to parent version and then check back.
In case if the labels still shown with transparent background then use the below CSS code in global custom CSS area under theme settings >> custom CSS:
.product-element-top.product-labels {
background:red;
}
Best Regards.
.
