Combo size if less items

How to change combo height if I have less items there?

default height defined through css
.dhx_combo_list{
position:absolute;
z-index:230;
overflow-y:auto;
overflow-x:hidden;
border:1px solid black;
height:100px; //< here it is

You can change it there, or include dhtmlxcombo_whp.js and use
combo.enableOptionAutoHeight(true)