https://ne-expo.com/js/form.js?v=2ysCh0s3IxYoP65ENNoUxixtpErCudpkUqigseRqC6A

1function focusInput() {
2    var className = "-sm";
3    var label = $(this).siblings("label");
4
5    if (!label.hasClass(className)) {
6        label.addClass(className);
7    }
8}
9
10function blurInput() {
11    var className = "-sm";
12    var _this = $(this);
13    var label = _this.siblings("label");
14    var value = _this.val().trim();
15
16    if (!value) {
17        label.removeClass(className);
18    }
19}
20
21$(function () {
22    var inputs = $(".form__input");
23
24    inputs.on("focus", focusInput);
25    inputs.on("blur", blurInput);
26
27    for (let i = 0; i < inputs.length; i++) {
28        const input = inputs[i];
29        if (input.value) {
30            $(input).siblings("label").addClass("-sm");
31        }
32    }
33});