select加下拉箭头

<div class="flex">
　　<label>城市</label>
　　<div class="dealerbo">
　　<select><option value="110000">北京市</option></select>
　　</div>
</div>

.dealerbo {
    border-bottom: 1px solid rgba(255, 255, 255, 0.5);
    position: relative;
    width: 99%;
    align-items: center;
    justify-content: space-between;
    background: url(../images/arrow_Down.png) no-repeat 100% center;
    overflow: hidden;
    padding-right: 5%;
    white-space: nowrap;
}
select {
    height: 27px;
    font-size: 14px;
    color: #000;
    border: none;
    background-color: transparent;
    padding-bottom: 5px;
    overflow: hidden;
    white-space: nowrap;
    width: 100%;
    text-overflow: ellipsis;
}