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">
    <link rel="stylesheet" href="./style.css">
    <title>Calendar App</title>
</head>
<body>
    <div class="container">

        <div id="calendar">

            <div id="current-month">
                <button id="back-btn"><</button>
                <div id="current-date">
                    <h1>Mars</h1>
                    <p>Monday 21, 2022</p>
                </div>
                <button id="next-btn">></button>
            </div>

            <div id="weekdays">
                <div>Sun</div>
                <div>Mon</div>
                <div>Tue</div>
                <div>Wed</div>
                <div>Thu</div>
                <div>Fri</div>
                <div>Sat</div>
            </div>

            <div id="days"></div>

        </div>

    </div>

    <script src="./script.js"></script>
</body>
</html>