index.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <title>JS Form Validation (with Bootstrap)</title>
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@3.4.1/dist/css/bootstrap.min.css"
          integrity="sha384-HSMxcRTRxnN+Bdg0JdbxYKrThecOKuH5zCYotlSAcp1+c8xmyTe9GYg1l9a69psu" crossorigin="anonymous">
    <link rel="stylesheet" href="style.css">
  </head>
  <body>
    <h1 id="text-center">Register With Us</h1>
    <div class="alert" id="msg"></div>
    <form id="regForm">
      <div class="form-group">
        <label for="name">Name<span class="required">*</span></label>
        <input type="text" class="form-control" id="name" placeholder="Name" autocomplete/>
      </div>
      <div class="form-group">
        <label for="email">Email<span class="required">*</span></label>
        <input type="email" class="form-control" id="email" placeholder="Email" autocomplete/>
      </div>
      <div class="form-group">
        <label for="password">Password<span class="required">*</span></label>
        <input type="password" class="form-control" id="password" placeholder="Password">
      </div>
      <div class="form-group">
        <label for="confirm-password">Confirm Password<span class="required">*</span></label>
        <input type="password" class="form-control" id="confirm-password" placeholder="Repeat your Password">
      </div>
    <button type="submit" class="btn btn-default">Submit</button>
    </form>

    <script src="main.js"></script>
  </body>
</html>