Z-index in front of an element in a fixed position

Question

I do not find a solution to my problem so I turn to you :).

Here is the context: I have two brothers elements, one is absolute position and the other is in a fixed position. Basic the fixed element is always at the top. Consider in the code below:

* {
  box-sizing: border-box;
}
html, body{
  margin: 0;
  padding: 0;
  height: 100%;
  width: 100%;
}
#element1 {
  background: red;
  height: 100%;
  width: 100%;
  position: absolute;
}
#element2 {
  background: green;
  margin: 0 auto;
  height: 200px;
  position: absolute;
  width: 600px;
}
#element3 {
  background: blue;
  height: 200px;
  position: fixed;
  bottom: 0;
  width: 100%;
}

#element1,
#element3 {
  z-index: 1;
}	
#element2 {
  z-index: 10;
}

<div id="element1">
  <div>
     <div id="element2"></div>
  </div>
</div>
<div id="element3">

</div>

http://jsfiddle.net/P7c9q/1162/

That the green color area is a modal. My objective is to make the element green over the element in a fixed position.

How can I unlock myself knowing that element 1 and element 2 must remain in absolute position?

Thank you in advance, cordially.

Answer 1

element3 will always be over element1 and all its children even if a child of element1 has higher z-index because its finally related to its parent element1 which has lower z-index than element3

There are two solutions to this case:

1. put element2 and element3 as children for element1

* {
  box-sizing: border-box;
}
html, body{
  margin: 0;
  padding: 0;
  height: 100%;
  width: 100%;
}
#element1 {
  background: red;
  height: 100%;
  width: 100%;
  position: absolute;
}
#element2 {
  background: green;
  margin: 0 auto;
  height: 200px;
  position: absolute;
  width: 600px;
}
#element3 {
  background: blue;
  height: 200px;
  position: fixed;
  bottom: 0;
  width: 100%;
}

#element1,
#element3 {
  z-index: 1;
}	
#element2 {
  z-index: 10;
}

<div id="element1">
  <div>
     <div id="element2"></div>
  </div>
  <div id="element3">

  </div>
</div>

2. make element2 outside element1 in the same level with element3

* {
  box-sizing: border-box;
}
html, body{
  margin: 0;
  padding: 0;
  height: 100%;
  width: 100%;
}
#element1 {
  background: red;
  height: 100%;
  width: 100%;
  position: absolute;
}
#element2 {
  background: green;
  top:25%;
  left:15%;
  margin: 0 auto;
  height: 200px;
  position: fixed;
  width: 600px;
}
#element3 {
  background: blue;
  height: 200px;
  position: fixed;
  bottom: 0;
  width: 100%;
}

<div id="element1"></div>
<div id="element2"></div>
<div id="element3"></div>