#demoCuatro, #demoIzq, #demoIzq2, #demoDer, #demoMed { border:1px dashed; width:136px; background-color:#e5e5e5; text-align:center; margin:0 1px 0 1px; }

#demoCuatro, #demoIzq, #demoDer, #demoMed { float:right; }

select { width:130px; }