popup.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="style.css">
</head>
<body>
    <div class = 'container1'>
        <label for="apiKey">Enter API Key</label>
        <div class = 'on-off'>
            <label for="toggleSwitch">ON/OFF:</label>
            <input type="checkbox" id="toggleSwitch">
        </div>
    </div>

    <div class = 'apiEntry'>
        <input type="password" id="apiKey" name="apiKey" placeholder="Your API Key">
        <button id="showBtn">Show</button>
    </div>
    <div class = 'buttons'>
        <button id="submitBtn">Submit API Key</button>
        <button id="removeBtn">Remove Stored API Key</button>
    </div>
    <script src = 'popup.js'></script>
</body>

</html>