<h1 class="page-header">Multi-Step Form with CSS Only</h1>
<div class="form-container">
  <form action="" role="form">
    <input id='step2' type='checkbox'>
    <input id='step3' type='checkbox'>

    <div id="part1" class="form-group">
      <div class="panel panel-primary">
        <div class="panel-heading">
          <h3 class="panel-title">Part 1</h3>
        </div>
        <input type="text" id="name" class="form-control" placeholder="Full Name" aria-describedby="sizing-addon1">
        <div class="btn-group btn-group-lg" role="group" aria-label="...">
          <label for='step2' id="continue-step2" class="continue">
            <div class="btn btn-default btn-success btn-lg">Continue</div>
          </label>
        </div>
      </div>
    </div>

    <div id="part2" class="form-group">
      <div class="panel panel-primary">
        <div class="panel-heading">
          <h3 class="panel-title">Part 2</h3>
        </div>
        <input type="email" id="email" class="form-control" placeholder="Email">
        <input type="phone" id="phone" class="form-control" placeholder="Phone">
        <input type="number" id="zip" class="form-control" placeholder="Zip Code">
        <div class="btn-group btn-group-lg btn-group-justified" role="group" aria-label="...">

          <label for='step2' id="back-step2" class="back">
            <div class="btn btn-default btn-primary btn-lg" role="button">Back</div>
          </label>


          <label for='step3' id="continue-step3" class="continue">
            <div class="btn btn-default btn-success btn-lg" role="button">Continue</div>
          </label>

        </div>
      </div>
    </div>

    <div id="part3" class="form-group">
      <div class="panel panel-primary">
        <div class="panel-heading">
          <h3 class="panel-title">Part 3</h3>
        </div>
        <textarea id="message" class="form-control" placeholder="Message"></textarea>
        <div class="btn-group btn-group-lg" role="group" aria-label="...">
          <label for='step3' id="back-step3" class="back">
            <div class="btn btn-default btn-primary btn-lg">Back</div>
          </label>
          <label class="continue">
            <button type="submit" class="btn btn-default btn-success btn-lg">Submit</button>
          </label>
        </div>
      </div>
    </div>
  </form>
</div>

body {
  text-align: center;
  background: url(http://subtlepatterns2015.subtlepatterns.netdna-cdn.com/patterns/upfeathers.png);
}
.form-container {
  width: 100%;
  max-width: 320px;
  margin: 0 auto;
  input[type=text], input[type=email], input[type=phone], input[type=number], textarea {
    width: 90%;
    margin: 20px auto;
    border: 1px solid white;
    box-shadow: 0  0 1px 1px white;
  }
  textarea {
    min-height: 150px;
  }
  .panel {
    background: rgba(0,0,0,.2);
    .panel-heading {
      margin-bottom: 20px;
    }
  }
  .btn-group {
    width: 90%;
    margin: 0 auto 10px auto;
  }
  .back {
    float: left;
  }
  .continue {
    float: right;
  }
}

/* Multi-Part CSS */
input[type=checkbox] {
  position: absolute;
  /* Position the checkbox in upper left corner */
  
  opacity: 0;
}

/* Styling Parts */
#part1,
#part2,
#part3 {
  z-index: 2;
  display: block;
  height: auto;
  opacity: 1;
  transition: opacity 1s ease-in-out;
}

/* Hidden Parts */
#part2,
#part3 {
  opacity: 0;
  height: 0;
  overflow: hidden;
}

/* Show Step 2 & Hide Step 1 */
#step2:checked ~ #part2 {
  opacity: 1;
  height: auto;
}
#step2:checked ~ #part1 {
  opacity: 0;
  height: 0;
  display: none;
}

/* Show Step 3  & Hide Step 2 */
#step3:checked ~ #part3 {
  opacity: 1;
  height: auto;
}
#step3:checked ~ #part2 {
  opacity: 0;
  width: 0;
  height: 0;
}