Define options for each pseudo states such as over, hover, and active or set options for custom media queries such as min-width: 500px, min-width: 800px, etc.
Use Case 1
Lets say you have a row or grid of items or images. As you resize the view you want to set different styles. With this feature you can add multiple queries and define the values in each one
Use Case 2
You have a text element and you want to change the background on hover. You open the element options, add or switch to the hover state and set the background color style. When you visit the page and move the mouse of the text, the background color changes.