Не работает ссылка в html/css + не выделяются h1-h2 тэги

.intro {
  display: flex;
  flex-direction: column;
  justify-content: center;
  width: 100%;
  height: 100vh;
  background: url("https://fotointeres.ru/wp-content/uploads/2014/03/Color-dreams.jpg") center no-repeat;
  -webkit-background-size: cover;
  background-size: cover;
}

.intro__inner {
  width: 100%;
  max-width: 880px;
  margin: 0 auto;
  text-align: center;
}

.intro__title {
  font-size: 150px;
  font-weight: bold;
  text-transform: uppercase;
  line-height: 1em;
  color: #fff;
}

.intro__title:after {
  content: "";
  display: block;
  margin: 60px auto;
  width: 60px;
  height: 3px;
  background-color: #fff;
}

.intro__suptitle {
  margin-bottom: 20px;
  font-size: 72px;
  color: #fff;
  font-family: 'Kaushan Script', cursive;
}


/* Button */

.intro__button {
  display: inline-block;
  vertical-align: top;
  padding: 8px 30px;
  border: 2px solid #fff;
  font-size: 14px;
  font-weight: bold;
  color: #fff;
  text-decoration: none;
  text-transform: uppercase;
}

.intro__button:hover {
  background-color: #fff;
  color: #000;
}

<div class="intro">

  <div class="container">
    <div class="intro__inner">
      <h2 class="intro__suptitle">Creative Template</h2>
      <h1 class="intro__title">Welcome to mogo</h1>

      <a class="intro__button" href="https://www.youtube.com/watch?v=S4lTtvlFvyk">Learn More</a>
    </div>
  </div>

</div>