How to perfectly center a div in a container

Question

The HTML code is :

<div class="header">

        <div class="div1">
            Division 1
        </div>

        <div class="div2">
            Division 2
        </div>

        <div class="div3">
            Division 3
        </div>

</div>

And the corresponding CSS code is:

.header{
    border: 2px solid red;
    text-align: center;
    height: 100px;
    overflow: hidden;
}

.div1{
    height: 150px;
    width: 150px;
    background-color: green;
    float:left;
}   

.div2{
    height: 150px;
    width: 100px;
    margin: 0 auto;
    background-color: orange;
    display: inline-block;
}

.div3{
    height: 150px;
    width: 50px;
    background-color: blue;
    float: right;   
}

It starts the div2 from the center of the screen but proceed in right direction. I want to make the div2's center on the center on the screen.

The current output is shown here: output

Answer 1

Make header position:relative and div2 position:absolute left and right to 0 see this fiddle. https://jsfiddle.net/xwzyoqn3/1/

.header{
    border: 2px solid red;
    text-align: center;
    height: 100px;
    overflow: hidden;
    width:100%;
    position:relative;
}

.div1{
    height: 150px;
    width: 150px;
    background-color: green;
    float:left;
}   

.div2{
    height: 150px;
    width: 100px;
    margin: 0 auto;
    background-color: orange;
    display: inline-block;
    position:absolute;
    left:0;
    right:0;
}