Changing the company's color

Suppose you work for an eCommerce company that sells cookies. The design team changed the company's logo color from blue to red, which caused many downstream changes to the company's landing page, ad creatives, and product packaging. The team did not did not perform an A/B test prior to the change. The lead designer wants to understand if the new color has impacted sales. Explain how you would design an analysis to understand sales impact.