html - How to stretch div height to fill parent div - CSS

Question

I have a page with divs like below

<div id="container">
    <div id="A"></div>
    <div id="B">
        <div id="B1"></div>
        <div id="B2"></div>
    </div>
    <div id="C"></div>
    <div id="D"></div>
</div>

with styling as;

html, body {
    margin: 0;
    padding: 0;
    border: 0;
}
#B, #C, #D {
    position: absolute;
}
#A{
    top: 0;
    width: 100%;
    height: 35px;
    background-color: #99CC00;
}
#B {
    top: 35px;
    width: 200px;
    bottom: 35px;
    background-color: #999999;
    z-index:100;
}
#B2 {
    margin-top: -35px;
    bottom: 0;
    background-color: #FFFFFF;
    width: 200px;
    overflow: scroll;
}
#B1 {
    height: 35px;
    width: 35px;
    margin-left: 200px;
    background-color: #CC0066;
}
#C {
    top: 35px;
    left: 200px;
    right: 0;
    bottom: 35px;
    background-color: #CCCCCC;
}
#D {
    bottom: 0;
    width: 100%;
    height: 35px;
    background-color: #3399FF;
}

See the layout / screenshot below;

I want to adjust the height of div B2 to fill (or stretch to) entire div B (marked with a green border) and don't want to cross footer div D. Here is a working fiddle demo(updated). How can I solve this??

Answer 1

Simply add height: 100%; onto the #B2 styling. min-height shouldn't be necessary.