去掉input type=number时的上下箭头

//火狐
input[type=number] {  
	-moz-appearance:textfield;  
}
//谷歌
input[type=number]::-webkit-inner-spin-button,  
input[type=number]::-webkit-outer-spin-button {  
	-webkit-appearance: none;  
    margin: 0;  
}