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HTML 

              
                  <form class="search-form">
    <input type="text" class="search" placeholder="City or State">
    <ul class="suggestions">
      <li>Filter for a city</li>
      <li>or a state</li>
    </ul>
  </form>

  <p class="love">Using JavaScript, replicate the <a href="http://wes.io/fAks" target="_blank">functionality found here</a>. <br>I'll post my answer once everyone has had a shot. <br>Tweet your answer <a href="https://twitter.com/wesbos">@wesbos</a></p>
!

CSS 

              
                    html {
      box-sizing: border-box;
      background: #ffc600;
      font-family: 'helvetica neue';
      font-size: 20px;
      font-weight: 200;
    }
    
    *,
    *:before,
    *:after {
      box-sizing: inherit;
    }
    
    input {
      width: 100%;
      padding: 20px;
    }
    
    .search-form {
      max-width: 400px;
      margin: 50px auto;
    }
    
    input.search {
      margin: 0;
      text-align: center;
      outline: 0;
      border: 0;
      border: 10px solid #F7F7F7;
      width: 120%;
      left: -10%;
      position: relative;
      top: 10px;
      z-index: 2;
      border-radius: 5px;
      font-size: 40px;
      box-shadow: 0 0 5px rgba(0, 0, 0, 0.12), inset 0 0 2px rgba(0, 0, 0, 0.19);
    }
    
    .suggestions {
      margin: 0;
      padding: 0;
      position: relative;
      /*perspective:20px;*/
    }
    
    .suggestions li {
      background: white;
      list-style: none;
      border-bottom: 1px solid #D8D8D8;
      box-shadow: 0 0 10px rgba(0, 0, 0, 0.14);
      margin: 0;
      padding: 20px;
      transition: background 0.2s;
      display: flex;
      justify-content: space-between;
      text-transform: capitalize;
    }
    
    .suggestions li:nth-child(even) {
      transform: perspective(100px) rotateX(3deg) translateY(2px) scale(1.001);
      background: linear-gradient(to bottom, #ffffff 0%, #EFEFEF 100%);
    }
    
    .suggestions li:nth-child(odd) {
      transform: perspective(100px) rotateX(-3deg) translateY(3px);
      background: linear-gradient(to top, #ffffff 0%, #EFEFEF 100%);
    }
    
    span.population {
      font-size: 15px;
    }
    
    .details {
      text-align: center;
      font-size: 15px;
    }
    
    .hl {
      background: #ffc600;
    }
    
    .love {
      text-align: center;
      line-height: 2;
    }
    
    a {
      color: black;
      background: rgba(0, 0, 0, 0.1);
      text-decoration: none;
    }
!

JS 

              
                // Fetch the top 1000 US cities by population json from this url and create a typeahead to filter by city or state name

// each city should be a <li> in the suggestions <ul>

// there is a span class of `hl` to highlight matches

// Demo: http://wes.io/fAks

var url = 'https://gist.githubusercontent.com/Miserlou/c5cd8364bf9b2420bb29/raw/2bf258763cdddd704f8ffd3ea9a3e81d25e2c6f6/cities.json';

// Good luck!
!
999px

Console