See attached we want to change it to square
Would you midn to share your store URL? Thanks!
Thanks for the info, check this one.
From your Shopify admin dashboard, click on “Online Store” and then “Themes”.
Find the theme that you want to edit and click on “Actions” and then “Edit code”.
In the “Assets” folder, click on “base.css, style.css or theme.css” file, depending on which file your theme uses to store its CSS styles. At the bottom of the file, add the following CSS code:
.variant-picker__option-values .block-swatch {
border-radius: 0;
}
And save.
Result:
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