IPlaceholder

You may have noticed the usage of IPlaceholder across the Circle and TextBlock placeholders. It is simply an interface defining the available width percentages that each placeholder could be.

Here is the interface definition:

interface IPlaceholderWidth {
    width:
    | '40%'
    | '65%'
    | '90%'
    | '93%'
    | '95%'
    | '97%'
    | '100%'
}