select input 样式

<span class="combo inputbtn">
<input type="text" class="combo-text" name="result_reg_id_name" id="result_reg_id_name"  readonly value="" style=" width:140px"/>
<span><span class="combo-arrow" onclick="setName();"></span></span>
<input type="hidden" class="combo-value" name="result_reg_id" id="result_reg_id" value=""/>
</span>

.inputbtn .combo-arrow{

background:url(images/icon-select.gif) no-repeat 50% 50%;

}