What is the purpose of the z-index and how is it used?
- The z-index helps specify the stack order of positioned elements that may overlap one another. The z-index default value is zero, and can take on either a positive or negative number.
- An element with a higher z-index is always stacked above one with a lower index.
- Z-Index can take the following values:
Auto: Sets the stack order equal to its parents.
Number: Orders the stack order.
Initial: Sets this property to its default value (0).
Inherit: Inherits this property from its parent element.