sizeBody();

window.onresize = sizeBody;

function sizeBody() {

    var bodyDiv = document.getElementById('BodyContainer');
    var bodyAct = document.getElementById('BodyActual');
    bodyDiv.style.Height = '';

    if(bodyAct.offsetHeight < document.body.clientHeight) {
        bodyDiv.style.height = (document.body.clientHeight - 115) + 'px';
    }
}