a img { 
border: none; 
}



#cabecera_css { position: absolute;
     top:0%; left: 120;
	    height: 50px;
     width:1200px;
     background-color:orange;	}


#menu_css {
     position: absolute;
     top:38px; left: 0;
	    height: 480px;
     width: 180px;
     background-color:white;
    }
#contenido_css {
     position: absolute;
     top:38px; left: 160px;
	    height: auto;
	    bottom: 0;
     width: 1070px;
     background-color:white;
    }