Width of Reviews in Grid/Masonry Style

Hi, I tried adding the following code to my “custom css” area of this plugin. I have also chosen the “grid / masonry” style for layout.

.woocommerce #reviews.woocommerce-Reviews #comments {
width: 100%;
}

It is not showing the width of the reviews at 100%. However there is a box to the right of the reviews — “Only logged in customers who have purchased this product may leave a review.” Is there a way to not display this message? Maybe then my reviews will show as 100%.

Here is my page:
https://savorthememories.com/shop/bee-baby-shower-pin/

Thank you!