index.html

<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="author" content="Nathan Manera Magalhães">
    <title id="titleHead"></title>
    <link rel="stylesheet" href="style.css">
    <script src="script.js"></script>
</head>
<body onload="setLanguage('pt-BR')">
    <div style="text-align: center; margin-top: 5vmin;">
        <span title="Set language to English" class="button" onclick="setLanguage('en-US')">English</span>
        <span title="Définir la langue en Français" class="button" onclick="setLanguage('fr-FR')">Français</span>
        <span title="Mudar idioma para Português" class="button" onclick="setLanguage('pt-BR')">Português</span>
    </div>
    <div class="age container">
        <div class="block">
            <p class="title" style="padding: 0;"><span id="txtToday"></span>:</p>
            <p><input type="text" id="today" disabled></p>

            <p class="title"><span id="txtBirthday"></span>:</p>
            <p>
                <input type="text" placeholder="dd/mm/yyyy" id="birthdate" oninput="mask(this, 'date')">
                <input type="text" placeholder="hh:mm" id="birthtime" value="00:00" oninput="mask(this, 'time')">
            </p> 
        </div>
        <div class="block">
            <p class="time" id="years"></p>
            <p class="time" id="months"></p>
            <p class="time" id="weeks"></p>
            <p class="time" id="days"></p>
            <p class="time" id="hours"></p>
            <p class="time" id="minutes"></p>
            <p class="time" id="seconds"></p>    
        </div>
    </div>
</body>
</html>