index.html

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>JQuery ui DatePicker with customize button</title>

    <link rel="stylesheet" href="https://code.jquery.com/ui/1.12.1/themes/base/jquery-ui.css">
    <style>
        .ui-datepicker .ui-datepicker-buttonpane button.ui-datepicker-current {
            float: none !important;
        }

        .pull-left {
            float: left !important;
        }
    </style>

</head>

<body>
    <input type="text" id="datepicker" class="input-class" />
    <script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
    <script src="https://code.jquery.com/ui/1.12.1/jquery-ui.js"></script>
    <script src="script.js"></script>


</body>

</html>