contador.html

<!DOCTYPE html>
<html lang="pt-br">
<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="https://fonts.googleapis.com/icon?family=Material+Icons">

    <link rel="stylesheet" href="styles.css">

    <title>Contador</title>
</head>
<body>
    <nav class="return-nav">
        <a href="index.html"><i class="material-icons">arrow_back</i></a>
    </nav>
    <main class="container-titulo-exercicio">   
        <h1 class="titulo-exercicio">Vamos Contar!</h1>
        <section class="exercicio-container primary-txt">
            <div class="forms-colunm">
                <div class="forms-colunm-item">
                    <label>Início:</label>
                    <input type="number" class="numeroInicioContador">
                </div>
                <div class="forms-colunm-item">
                    <label>Fim:</label>                       
                    <input type="number" class="numeroFimContador col-sm-10">
                </div>
                <div class="forms-colunm-item">
                    <label>Passo:</label>              
                    <input type="number" class="numeroPassoContador">
                </div>            
            </div>
            <button onclick="contar()" class="primary-btn margin-10px">Contar</button>
            <div class="resultadoContador">
                Preparando a contagem...
            </div>
            <button onclick="resetFormsContador()" class="limparTelaContador primary-btn margin-10px reset-forms">Limpar tela</button>
        </section>
    </main>   
    <script src="script.js"></script>    
</body>
</html>