#demoIzq { width:100%; text-align:left; }
#demoDer { width:100%; text-align:left; float:left;}

#files_list{width:100%;font-size : 0.7em; 
color : rgb(51, 51, 51); 
font-family : Verdana, Tahoma, Arial;
}
.elemento{
width:100%;
text-align:left;
}

/*select { width:220px; }*/