.form-container {
width: 30%;
  margin: 1em auto;
  background:#fff;
  box-shadow:0 0 10px 3px #959595;
  padding:20px 20px 20px 20px;
  min-height:300px;
  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: 100px;
  }
  .panel {
    background: rgba(0,0,0,.2);
    .panel-heading {
      margin-bottom: 20px;
    }
  }
  .btn-group {
    width: 90%;
    margin: 10px auto 0 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;
}

@media only screen and (max-width: 600px) {
  .form-container {
width: 90%;
  margin: 1em auto;
  background:#fff;
  box-shadow:0 0 10px 3px #959595;
  padding:20px 20px 20px 20px;
  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;
  }
}