function setFooter() {
var footer = document.getElementById("footer_azul"); 
footer.style.height = "155px"; 
var espacio_vertical_disponible = document.body.offsetHeight; 
var espacio_vertical_usado = document.getElementById("evu");
var aumento = espacio_vertical_disponible - espacio_vertical_usado.offsetHeight; 
var footer_actual = footer.offsetHeight;
 if(aumento > 0) {
 footer.style.height = (footer_actual + aumento) + "px";} }
window.onload = function() {setFooter();}
window.onresize = setFooter;