Missing template "layout/theme.liquid"

• When I upload the zip file to Shopify I get an error saying "zip does not contain a valid theme: missing template "layout/theme.liquid".

• The package you received from Themeforest has the following items: file, documentation, log.txt, readme

• Please Extract the whole package after downloading it from Themeforest. themeforest-xxxxx-brushstrokes-shopify-arts-portfolio-gallery-store-theme.zip,

• You files like brushstrokes-demo-01.zip, brushstrokes-demo-02.zip,brushstrokes-demo-03.zip , Log.txt and Readme.txt.

• You need to install the file "brushstrokes-demo-01.zip or brushstrokes-demo-02.zip or brushstrokes-demo-03.zip" in the shopify store