select下拉框右对齐，去掉箭头，替换箭头

右对齐

select{

   width:auto;

   direction: rtl;

}

select option {

　　direction: ltr;

}

去掉箭头（不设置背景色会有灰色背景）

select{

   appearance:none;

   -moz-appearance:none;

   -webkit-appearance:none;

   background-color: #fff;

   /*设置箭头*/

   background: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAwAAAAJCAYAAAAGuM1UAAAAH0lEQVR42mNgoDnQ13f7TwiTpIkkm0hyHkl+YhhQAABcfyjsqSyTLgAAAABJRU5ErkJggg==") no-repeat scroll right center transparent;

   padding-right: 14px;

}

清除ie的默认选择框样式，隐藏下拉箭头

select::-ms-expand {

   display: none;

}