Hey Guys, I am Garvit Motwani. In This article i will tell you about the z-index property in CSS.

What is a Z Index?

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.

The z-index property is specified as either the keyword auto or an <integer>.

Note: z-index only works on positioned elements (position:absolute, position:relative, or position:fixed).

What does the values do?

auto
The box does not establish a new local stacking context. The stack level of the generated box in the current stacking context is the same as its parent's box.

<integer>
This <integer> is the stack level of the generated box in the current stacking context. The box also establishes a local stacking context in which its stack level is 0. This means that the z-indexes of descendants are not compared to the z-indexes of elements outside this element.

Syntax And Values

/* Keyword value */ z-index: auto; /* <integer> values */ z-index: 0; z-index: 2; z-index: 300; z-index: -1; /* Negative values to lower the priority */ /* Global values */ z-index: inherit; z-index: initial; z-index: unset; 

Example

HTML

<h1>The z-index Property</h1> <img src="cat.jpg" width="100" height="140"> <p>Because the image has a z-index of -1, it will be placed behind the heading.</p> 

CSS

img { position: absolute; left: 0px; top: 0px; z-index: -1; } 

This will look like this:

HTML

<div class="dashed-box">Dashed box <span class="gold-box">Gold box</span> <span class="green-box">Green box</span> </div> 

CSS

.dashed-box { position: relative; z-index: 1; border: dashed; height: 8em; margin-bottom: 1em; margin-top: 2em; } .green-box { position: absolute; z-index: 3; /* put .green-box above .green-box and .dashed-box */ background: green; width: 80%; left: 60px; top: 3em; } .blue-box { position: absolute; z-index: 2; /* put .blue-box above .dashed-box */ background: blue; width: 20%; left: 65%; top: -25px; height: 7em; opacity: 0.9; } 

This one will look like this:

Thank You Guys For Reading this article. Hopefully it helped you.