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CSS

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JavaScript

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HTML 

              
                <div id="content">
  
  <div class="welcome">

    <h1 class="fade">a form for this section</h1>
    <button type="button" class="fade show btn">Show me the form</button>
  </div>
  
  <div class="content">
    <p>
      I made this to display some functionality I put together for a recent project.
    </p>
    
    <p>This uses jQuery to match a hidden form to the height of a welcome section.</p>
    
  </div>
  
</div>

<div id="form">
  <h2>
    Feed me your email!
  </h2>
  <form>
     <input type="text" placeholder="Your Email">
     <input type="submit">
   </form>
  <button class="btn close">Close</button>
</div>
!

CSS 

              
                body{
  font-family: helvetica;
  margin: 0;
  position: relative;
  min-height: 600px;
  text-align: center;
  font-size: 100%;
  color: #3e4651;
}


.welcome{
  padding: 4em 1em;
  background-color: #00b5b5;
  h1{
    margin: 0.5em 0;
    font-size: 3em;
    color: #fff;
  }
  .btn{
    background-color: transparent;
    border: 3px solid #fff;
    padding: 0.5em 2em;
    font-size: 1em;
    letter-spacing: 0.5px;
    color: #fff;
    font-weight: 700;
    cursor: pointer;
    outline: none;
    &:hover{
      background-color: #fff;
      color: #00b5b5;
    }
  }
}

.content{
  padding: 2em 1em;
  .btn{
    background-color: transparent;
    border: 3px solid #f1654c;
    padding: 0.5em 2em;
    font-size: 1em;
    letter-spacing: 0.5px;
    color: #f1654c;
    font-weight: 700;
    cursor: pointer;
    outline: none;
  }
}

#form{
  position: absolute;
  padding: 4em 1em;
  box-sizing: border-box;
  display: none;
  color: #fff;
  top: 0;
  left: 0;
  width: 100%;
  background: rgba(62,70,81,1);
  h2{
    font-size: 2em;
    margin: 0.5em;
  }
  .btn{
    position: absolute;
    top: 2em;
    right: 3em;
    background-color: transparent;
    border: 0;
    color: #768395;
    text-transform: uppercase;
    letter-spacing: 2px;
    cursor: pointer;
    outline: none;
    &:hover{
      color: #fff;
    }
    &:after{
      content: "+";
      color: #fff;
      display: inline-block;
      position: absolute;
      top: -0.33em;
      right: -0.8em;
      font-size: 2.4em;
      -webkit-transform: rotate(45deg);
       -moz-transform: rotate(45deg);
         -o-transform: rotate(45deg);
            transform: rotate(45deg);
    }
  }
  input[type=text]{
    color: #00b5b5;
    border: 2px solid #fff;
    padding: 0.3em 1em;
    font-size: 1.2em;
    font-weight: 700;
  }
  input[type=submit]{
    background-color: transparent;
    border: 3px solid #f1654c;
    padding: 0.5em 2em;
    font-size: 1em;
    letter-spacing: 0.5px;
    color: #fff;
    font-weight: 700;
    cursor: pointer;
    outline: none;
    &:hover{
      background-color: #f1654c;
      color: #fff;
    }
  }
}
!

JS 

              
                $(document).ready(function(){
   
  var formHeight = $('.welcome').outerHeight();
  var welcomeHeight = $('.welcome').height();
  // Create function to have matched heights
  function getFormHeight(){
    $('.welcome').css("height", welcomeHeight);
    $('#form').css("min-height", formHeight);
  }
  
  function changeWelcomeHeight(){
    var newWelcomeHeight = $('#form').height();
  }
  
  // Run our function to get heights
  getFormHeight();
  
  // Fade and Show elements when 'share your ideas' button clicked
  $('.show').on('click', function(){
    $('.fade').fadeOut("slow");
    $('#form').delay(300).fadeIn("slow");
  });
  
  // Fade and Show elements when 'close' button clicked
  $('.close').on('click', function(){
    $('#form').fadeOut("slow");
    $('.fade').fadeIn("slow");
  });
  
  $( window ).resize(function() {
     if ( $('#form').css('display') != 'none' ) {
		changeWelcomeHeight();
     }
	});

});
!
999px

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