<div class="phone">
  <div class="card">
    <div class="card__contents">
      <div class="card__title">Welcome</div>
      <div class="card__body">
        <p>Are you too tired of high premiums?</p>
        <p>We're the insurance company that sends you the money directly!</p>
        <p>Interested? Jump in!</p>
      </div>
      <div class="card__next">next →</div>
    </div>
    <div class="card__shadow">
      <div class="card__shadow-inner"></div>
    </div>
    <div class="card__index">1</div>
  </div>
  <div class="card">
    <div class="card__contents">
      <div class="card__title">Who are you?</div>
      <div class="card__body">
        <p>What's your email address?</p>
        <input class="card__input" type="email">
      </div>
      <div class="card__next">next →</div>
    </div>
    <div class="card__shadow">
      <div class="card__shadow-inner"></div>
    </div>
    <div class="card__index">2</div>
  </div>
  <div class="card">
    <div class="card__contents">
      <div class="card__title">Solar system</div>
      <div class="card__body">
        <p>Which planet do you live on?</p>
        <input class="card__input" type="text">
      </div>
      <div class="card__next">next →</div>
    </div>
    <div class="card__shadow">
      <div class="card__shadow-inner"></div>
    </div>
    <div class="card__index">3</div>
  </div>
  <div class="card">
    <div class="card__contents">
      <div class="card__title">Money</div>
      <div class="card__body">
        <p>How do you want the money?</p>
        <input class="card__radio" type="radio" name="cash" id="cash"><label for="cash">Cash</label>
        <input class="card__radio" type="radio" name="cash" id="account"><label for="account">Bitcoins</label>
      </div>
      <div class="card__next">next →</div>
    </div>
    <div class="card__shadow">
      <div class="card__shadow-inner"></div>
    </div>
    <div class="card__index">4</div>
  </div>
  <div class="card">
    <div class="card__contents">
      <div class="card__title">Almost there...</div>
      <div class="card__body">
        <p>As always, do you want to sign up for yet another newsletter?</p>
        <input class="card__check" type="checkbox" id="newsletter"><label for="newsletter">Spam me!</label>
      </div>
      <!-- <div class="card__next">next →</div> -->
    </div>
    <div class="card__shadow">
      <div class="card__shadow-inner"></div>
    </div>
    <div class="card__index">5</div>
  </div>
</div>

body {
  align-items: center;
  justify-content: center;
  background: #f2f2f2;
  display: flex;
  font-family: 'Nunito Sans', sans-serif;
  font-size: 1.125em;
  height: 100vh;
  margin: 0;
}
.phone {
  background: white;
  height: 100%;
  max-width: 360px;
  overflow: hidden;
  position: relative;
  width: 100%;
}
.card {
  height: 100%;
  position: absolute;
  text-align: center;
  transition: transform 300ms;
  width: 100%;
}
.card:nth-child(2) {
  transform: translateX(100%);
}
.card:nth-child(3) {
  transform: translateX(100%);
}
.card:nth-child(4) {
  transform: translateX(100%);
}
.card:nth-child(5) {
  transform: translateX(100%);
}
.card__contents {
  align-items: center;
  display: flex;
  flex-direction: column;
  height: 100%;
  position: absolute;
  top: 0;
  width: 100%;
}
.card:nth-child(1) .card__contents {
  background: #fff;
}
.card:nth-child(2) .card__contents {
  background: #C9F9E1;
  -webkit-clip-path: polygon(10% 0%, 10% 20%, 0% 20%, 0% 100%, 100% 100%, 100% 0%);
  clip-path: polygon(10% 0%, 10% 20%, 0% 20%, 0% 100%, 100% 100%, 100% 0%);
}
.card:nth-child(3) .card__contents {
  background: #F9C9C7;
  -webkit-clip-path: polygon(10% 0%, 10% 40%, 0% 40%, 0% 100%, 100% 100%, 100% 0%);
  clip-path: polygon(10% 0%, 10% 40%, 0% 40%, 0% 100%, 100% 100%, 100% 0%);
}
.card:nth-child(4) .card__contents {
  background: #F9F0C7;
  -webkit-clip-path: polygon(10% 0%, 10% 60%, 0% 60%, 0% 100%, 100% 100%, 100% 0%);
  clip-path: polygon(10% 0%, 10% 60%, 0% 60%, 0% 100%, 100% 100%, 100% 0%);
}
.card:nth-child(5) .card__contents {
  background: #E6C9F9;
  -webkit-clip-path: polygon(10% 0%, 10% 80%, 0% 80%, 0% 100%, 100% 100%, 100% 0%);
  clip-path: polygon(10% 0%, 10% 80%, 0% 80%, 0% 100%, 100% 100%, 100% 0%);
}
.card__title {
  font-weight: 800;
  font-size: 2em;
  margin-top: 20px;
}
.card__body {
  margin-top: 20px;
  max-width: 200px;
}
.card__input {
  background: transparent;
  border: 0;
  border-bottom: 2px solid black;
  font-size: 1em;
  outline: none !important;
}
.card__input:focus {
  border-width: 4px;
}
.card__radio {
  margin-right: 10px;
  vertical-align: baseline;
}
.card__check {
  margin-right: 10px;
}
.card__next {
  -webkit-tap-highlight-color: transparent;
  bottom: 20px;
  cursor: pointer;
  margin-top: 50px;
  position: absolute;
  right: 20px;
  user-select: none;
}
.card__shadow {
  overflow: hidden;
  pointer-events: none;
  position: absolute;
  top: 0;
  width: 10%;
}
.card__shadow-inner {
  box-shadow: inset 0 0 6px rgba(50,50,50,.12);
  height: calc(100% + 15px);
  left: -15px;
  position: relative;
  top: -15px;
  width: calc(100% + 15px);
}
.card:nth-child(1) .card__shadow {
  height: 0;
}
.card:nth-child(2) .card__shadow {
  height: 20%;
}
.card:nth-child(3) .card__shadow {
  height: 40%;
}
.card:nth-child(4) .card__shadow {
  height: 60%;
}
.card:nth-child(5) .card__shadow {
  height: 80%;
}
.card__index {
  align-items: center;
  cursor: pointer;
  display: flex;
  height: 20%;
  justify-content: center;
  position: absolute;
  text-align: center;
  width: 10%;
  z-index: 1;
}
.card:nth-child(1) .card__index {
  top: 0;
}
.card:nth-child(2) .card__index {
  top: 20%;
}
.card:nth-child(3) .card__index {
  top: 40%;
}
.card:nth-child(4) .card__index {
  top: 60%;
}
.card:nth-child(5) .card__index {
  top: 80%;
}

const cards = document.querySelectorAll('.card'),
      nexts = document.querySelectorAll('.card__next'),
      ixs = document.querySelectorAll('.card__index');
nexts.forEach((next, i) => {
  next.addEventListener('click', function() {
    cards[i + 1].style.transform = 'none';
  });
});
ixs.forEach((index, i) => {
  index.addEventListener('click', () => {
    for (let j = ixs.length - 1; j > i; j--) {
      cards[j].style.transform = 'translateX(100%)';
    }
    console.log(i);
  })
});