button.ui-multiselect{
    font-family:inherit;
    font-size: 11px !important;
    font-weight:normal;
    color:#333;
    background-color: #fff;
    background-image: none;
    border: 1px solid #c6c6c6;
    border-radius: 3px;
    transition: border-color 0.15s ease-in-out 0s, box-shadow 0.15s ease-in-out 0s;
    padding:3px 0 3px 4px  !important;
     margin-left: 5px;
}

 button.ui-state-default .ui-icon{
    background-image: url("imagenes/jquery-ui/images/ui-icons_222222_256x240.png") !important;
}