The z-index property specifies the stack order of an element. An element with greater stack order is always in front of an element with a lower stack order. Note: z-index only works on positioned elements (position:absolute, position:relative, or position:fixed).

Value Description
(numeric)If you had 2 absolutely positioned elements that overlapped and you gave element A a z-index value of 5 and element B a z-index value of 10, element B would show in front of element A.

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