CSS3 appearance Property

.thing { -webkit-appearance: none; -moz-appearance: none; appearance: none;}
select::-ms-expand {display:none}
select{ position:relative; border:0; -webkit-appearance:none; -moz-appearance:none; appearance:none; text-indent:0.01px; text-overflow: '';}

https://developer.mozilla.org/en-US/docs/Web/CSS/-moz-appearance