JSFiddle - React, Tailwind, and code Playground

HTML

<form>
    <input type="password" name="user_pass" class="NumCon" id="7">
</form>

JavaScript

function NumCon() {
        var result = true;
        $(this).closest("form").find('.NumCon').each(function () {
            var size = this.value.length;
            var NumVal = $(this).attr('id');
            if (size <= NumVal) {
                $(this).css("background", "#ffc4c4");
                result = false;
            }else{
                $(this).css("background-color", "#ffffec");
            }
        });
    }
    
    $('.NumCon').live('keyup', NumCon());