JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://youthcore.ca/res/js/mootools-datepicker/Source/Locale.en-US.DatePicker.js"></script>
<script src="http://youthcore.ca/res/js/mootools-datepicker/Source/Picker.js"></script>
<script src="http://youthcore.ca/res/js/mootools-datepicker/Source/Picker.Attach.js"></script>
<script src="http://youthcore.ca/res/js/mootools-datepicker/Source/Picker.Date.js"></script>
<input type="text" value="" style="margin-left:50px;">

CSS

.datepicker {
    position: absolute;
    border: 2px solid #1C3262;
    font-size: 11px;
    width: 194px;
    padding: 3px;
    height: 221px;
    background: #fff;
    line-height: normal;
    z-index: 3003;
}
/* header
********************************************************/
 .datepicker .header {
    position: relative;
    background: #1C3262;
    height: 21px;
    padding-top: 4px;
    margin-bottom: 3px;
}
.datepicker .header .title {
    text-align: center;
    padding-top: 1px;
    margin: 0px 42px 0 20px;
}
.datepicker .header .titleText {
    color: #fff;
    font-weight: bold;
}
.datepicker .header .next, .datepicker .header .previous, .datepicker .header .closeButton {
    position: absolute;
    width: 15px;
    height: 15px;
    background: #fff;
    text-align: center;
    color: #666;
    top: 5px;
    cursor: pointer;
}
.datepicker .header .previous {
    left: 5px;
}
.datepicker .header .next {
    right: 28px;
}
.datepicker .header .closeButton {
    right: 5px;
}
/* body
********************************************************/
 .datepicker .body {
    position: relative;
    top: 0px;
    left: 0px;
    width: 194px;
    border-right: 2px solid #fff;
    height: 193px;
    overflow: hidden;
}
/* time
********************************************************/
 .datepicker .time {
    width: 100%;
    height: 100%;
    background: #eee;
}
.datepicker .time .hour, .datepicker .time .separator, .datepicker .time .minutes {
    border: 1px solid #ccc;
    background: #fff;
    width: 50px;
    font-size: 32px;
    position: absolute;
    top: 50px;
    text-align: center;
    padding: 2px;
}
.datepicker .time .hour {
    left: 30px;
}
.datepicker .time .separator {
    background: transparent;
    border: 0px;
    width: 10px;
    left: 91px;
}
.datepicker .time .minutes {
    left: 110px;
}
.datepicker .time .ok {
    position: absolute;
    top: 105px;
    width: 136px;
    left: 30px;
    font-size: 20px;
}
/*...

JavaScript

window.addEvent('domready', function () {

    var language = window.navigator.userLanguage || window.navigator.language;
    console.log(language);
    var list = Locale.list().length;
    for (var i = 0; i < list; i++) {
        if (Locale.list()[i] == language) {
            Locale.use(language);
        } else {
            var langArray = language.split('-');
            var locArray = Locale.list()[i].split('-');
            for (var k = 0; k < list; k++) {
                if (langArray[0] == locArray[0]) {
                    Locale.use(Locale.list()[i]);
                }
            }
        }
    }
    console.log(Locale.getCurrent().name);
    myPicker = new Picker.Date($$('input'), {
			toggle: $$('.toggle'),
			positionOffset: {x: -10, y: 20}
		});

});