Lets assume I have the following layout (see image below)... I have a header (A) at the top, footer (C) that is always at the bottom and container (B) that is in the middle
Depending on how your page is set up, it may work if you set height: 100%; for (B) and position: absolute; for the container element. Here is an example:
HTML:
CSS:
#container {
height: 100%;
width: 100%;
background: green;
position: absolute;
}
#header, #footer {
height: 100px;
width: 100%;
background: red;
}
#body {
height: 100%;
width: 100%;
background: blue;
}
jsFiddle