Js修改select下拉框及option默认颜色

<script>
	var unSelected = "#d8d8d8";
    var selected = "#3c3c3c";
    $(function () {
        $("select").css("color", unSelected);
        $("select>option").css("color", selected);
        $("select").change(function () {
            var selItem = $(this).val();
            if (selItem == $(this).find('option:first').val()) {
                $(this).css("color", unSelected);
            } else {
                $(this).css("color", selected);
            }
        });
	});
</script>