Z-Index and Stacking Context

Z-index in CSS controls the vertical stacking order of elements that overlap. Elements with a higher z-index value will appear in front of elements with a lower z-index value. Stacking context is a three-dimensional conceptualization of HTML elements along an imaginary z-axis relative to the viewer, which determines the order in which elements appear in front of or behind each other.

Visit the following resources to learn more:

• @article@z-index
• @video@CSS Z Index Property: What is CSS Z-Index, Stacking Order, and Why Your Z-Index Is Not Working?