Working with theme variants

Let's assume we have created a new design package called sportswear_package. Within this design package, create a new theme and call it sportswear_theme. Our new design package file hierarchy, in /app/design/, might resemble the following hierarchy:

app/
  design/
    frontend/
      Magento/
        blank/
        luma/      
      sportswear_package/
        sportswear_theme/

Because we want to use the blank theme as a starting point, the theme.xml in the root directory of our theme will look something like this:

<theme xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../../../lib/internal/Magento/Framework/Config/etc/theme.xsd">
    <title>Sportswear Theme</title>
    <parent>Magento/blank</parent>
    <media>
        <preview_image>media/preview.jpg</preview_image>
    </media>
</theme>

However, let's also take one more customization step here. We can create variations...