How to revert the logo to its original color/shape on Article view

Indeed, there is an extra color filter for the logo that is enabled in single Article view and the Checkout page from EasyStore. Please use Custom CSS to disable the effect:

.com-content.view-article #sp-logo img, 
.com-easystore.view-checkout #sp-logo img {filter: none !important;}

and logo will return to its original colors/shapes.