JavaScript DOM/Simple DOM Programs/3.html

<html>
    <head>
        <style>
            .items{
                display: flex;
                flex-direction: column;
                width: 600px;
            }
            .container{
                display: grid;
                place-items: center;
            }
            .items input, button,select{
                width: 400px;
                margin-top: 20px;
                height: 40px;
            }
        </style>
    </head>
    <body>
        <div class="container">
            <div class="items">
                <input type="number" name="" id="num1">
                <input type="number" name="" id="num2">
                <select id="select-operation">
                    <option value="Sum">Sum</option>
                    <option value="Subtraction">Subtraction</option>
                    <option value="Multiplication">Multiplication</option>
                    <option value="Division">Division</option>
                </select>
                <button id="btn">Result</button>
                <h1 id="result"></h1>
            </div>
        </div>
        <script src="3.js">
        </script>
    </body>
</html>