how i core calm between header footer div?

in before question, i scholastic keep footer div during bottom page. ()

now i'm perplexing plumb core calm between header footer divs.

so i've got is:

#divheader
{
    height: 50px;
}

#divcontent
{
    position:absolute;
}

#divfooter
{
    height: 50px;
    position:absolute;
    bottom:0;
    width:100%;
}
<div id="divheader">
    header
</div>
<div id="divcontent">
    content
</div>
<div id="divfooter">
    footer
</div>

i've attempted formulating progenitor div residence existent 3 divs giving div vertical-align:middle; nonetheless gets me nowhere.