#contenedor { margin: 0 auto; width:500px; overflow: hidden;}
#menu { list-style:none;}
#menu li {display:inline; padding:3px 5px 3px 5px;}
#menu li a{ text-decoration:none;}
#ventana {overflow:hidden;}
#mostrador {width:1500px; margin:10px;}
.tabs {float:left;}
.tab1 { background-color:#e8e8e8;}
.tab1 a {color:#5b5959;}
.tab2 {background-color:#cc4148;}
.tab2 a, .tab3 a{ color:#FFF;}
.tab3 {background-color:#d59530;}
#tab2, #tab3 { visibility:hidden;}

#tab1 { background:#e8e8e8; padding:3px 0; margin-top:-13px; width:500px;}
#tab2 { background:#cc4148; padding:3px 0; margin-top:-13px; width:500px;}
#tab3 { background:#d59530; padding:3px 0; margin-top:-13px; width:500px;}