#contenedor {background-color: #3AE2CE;text-align:left;width: 960px;height: 100%;margin-left: auto;margin-right: auto;}
#col_der, #col_izq, #col_cen {height: 100%;}

#col_cab {background-color: #ccc;height: 130px;}
#col_izq {float: left; width: 210px;background-color: #E8E8E8;}
#col_cen {text-align:left;background-color: #FFFFFF;}
#col_der {float: right; width: 210px;background-color: #E8E8E8;}
#col_pie {background-color: #F00FFF;width: 960px;height: 35px;}

.corte {clear: both;} 

body {width: 100%; height: 100%;}