select选中事件用change，（用click会执行两次）；

select标签对移动端的兼容：

.custom-selectselect{

width:100%; margin:0;

background:none;

border:1px solid transparent;

outline: none;/* Prefixed box-sizing rules necessary for older browsers */

-webkit-box-sizing: border-box;

-moz-box-sizing: border-box;

box-sizing: border-box;/* Remove select styling */ appearance: none;

-webkit-appearance: none;/* Font size must the 16px or larger to prevent iOS page zoom on focus *//* General select styles: change as needed */

font-family: helvetica, sans-serif;

font-weight: bold;

color:#444;

padding:.6em1.9em.5em.8em;

line-height:1.3;}

.custom-select::after{

content:"";

position: absolute;

width:0px;

height:0px;

top:50%;

right:8px;

margin-top:-4px;

border:8px solid #929497;

border-width:8px5px8px;

border-color:#929497 transparent transparent transparent;

z-index:2;

pointer-events:none;

}