function getWindowHeight() {
            var windowHeight = 0;
            if (typeof(window.innerHeight) == 'number') {
                windowHeight = window.innerHeight;
            }
            else {
                if (document.documentElement &&
document.documentElement.clientHeight) {
                    windowHeight = document.documentElement.clientHeight;
                }
                else {
                    if (document.body && document.body.clientHeight) {
                        windowHeight = document.body.clientHeight;
                    }
                }
            }
            return windowHeight;
        }
        function setFooter() {
            if (document.getElementById) {
                var windowHeight = getWindowHeight();
                if (windowHeight > 0) {
                    var contentHeight = document.getElementById
('contenedor').offsetHeight;
					var footerElement = document.getElementById('fondo-inferior');
					if ( document.getElementById('contenido-internas') ) {
						var contene = document.getElementById('contenido-internas');
					    var conteneHeight = document.getElementById('contenido-internas').offsetHeight;
						if (conteneHeight < 900) {
							contene.style.height = 900 + 'px';
							footerElement.style.top = (660) + 'px';
						}
						else {
							footerElement.style.top = (contentHeight - 520) + 'px';
						}
					}
					
					else {
					if ( document.getElementById('una-central') ) {
						var contene = document.getElementById('una-central');
					    var conteneHeight = document.getElementById('una-central').offsetHeight;
						if (conteneHeight < 900) {
							contene.style.height = 900 + 'px';
							footerElement.style.top = (730) + 'px';
						}
						else {
							footerElement.style.top = (contentHeight - 520) + 'px';
						}
					}
					else {
						var contene = document.getElementById('contenido');
					    var conteneHeight = document.getElementById('contenido').offsetHeight;
						if (conteneHeight < 900) {
							//difere = 900-conteneHeight;
							contene.style.height = 900 + 'px';
							footerElement.style.top = (575) + 'px';
						}
						else {
							footerElement.style.top = (contentHeight - 520) + 'px';
						}
					}
					}
                }
            }
        }
        window.onload = function() {
            setFooter();
        }
        window.onresize = function() {
            setFooter();
        }