Campaign container with cookie-based password

campaign.html

<!--- Starting april 2021 campaign container -->
    <div id="campaign-container">
        <img src="http://s.mmgo.io/t/CAm7" alt="motionmailapp.com" />
        <div class="form-container">
            Enter password for early-access to this campaign
            <input type="password" placeholder="Enter password here" name="" id="campaign_password">
            <button id="campaign_button">Let me in</button>
        </div>
    </div>
    <style>
        #campaign-container {
            position: fixed;
            top: 0;
            left: 0;
            bottom: 0;
            height: 100%;
            width: 100%;
            background-image: url(content/img/april-21-campaign-bg.jpeg);
            background-size: cover;
            justify-content: center;
            text-align: center;
            padding-top: 30vh;
            background-position: center center;
            background-repeat: no-repeat;
        }
        input#campaign_password {
            display: block;
            width: 100%;
            padding: 1rem;
            box-sizing: border-box;
            margin: 1rem auto;
            border-radius: 4px;
            border: 1px solid #999;
        }
        button#campaign_button {
            display: block;
            box-sizing: border-box;
            width: 100%;
            padding: 1rem;
            font-weight: bold;
            background: #000;
            color: #fff;
            border: none;
            border-radius: 4px;
            font-size: 16px;
            text-transform: uppercase;
        }
        #campaign-container .form-container {
            background: #fff;
            max-width: 350px;
            margin: 1rem auto;
            padding: 3rem;
            box-shadow: 0 1px 10px rgb(0 0 0 / 20%);
            border-radius: 10px;
            display:none; /** Set this to display:block; to display the form **/
        }
    </style>
    <script>
        let validToPass = TopBarGetCookie('campaign_password_valid');
        let campaignContainerId = 'campaign-container';
        const campaignPassword = 'LetMeInNow!';

        if (validToPass) {
            //Hide campaign container
            //document.getElementById(id).style.display = 'block';
            document.getElementById(campaignContainerId).style.display = 'none';
        }
        document.getElementById('campaign_button').onclick = function() {
            if(document.getElementById('campaign_password').value === campaignPassword){
                TopBarSetCookie('campaign_password_valid', 1);
                document.getElementById(campaignContainerId).style.display = 'none';
            } else {
                alert('This is not correct password. Please wait until campaign starts ...')
            }
        };
    </script>