3.0 Gallery Thumbnails Not Displaying Correctly

I recently upgraded my product gallery to the latest version. Everything is working as it should. However, something in my child theme is overwriting the formatting for the product gallery thumbnails.

I have added:

add_filter( ‘woocommerce_get_image_size_gallery_thumbnail’, function( $size ) {
return array(
‘width’ => 150,
‘height’ => 150,
‘crop’ => 0,
);
} );

to functions.php. This has worked to make the images clear and not blurry.

I also tried adding:

.single-product div.product .woocommerce-product-gallery .flex-control-thumbs {
margin: 0 -5px; /* align left and right gallery with main image */
}
.single-product div.product .woocommerce-product-gallery .flex-control-thumbs li img {
/* force a thumbnail size */
width: 160px;
padding: 25px 50px 75px 100px;
}

to main.css in order to add padding around the images. However, this had no effect at all.

Can anyone point me to the file that may be causing the standard woocommerce formatting to be overwritten?

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