css - div内のリストのときにcssタブ付きメニューのコンテンツが表示されない

Question

タブを選択すると、同じページ内にコンテンツが表示されます。

div がなくても (リストのように) 正常に動作します。動作中の JSFIDDLE を参照してください。ただし、div を使用すると、コンテンツはまったく表示されません。問題のある JSFIDDLE はこちら

これはそれほど難しいことではないと確信していますが、問題がわかりません。

誰でもアドバイスできますか？

作業中の HTML:

<ul class="tabs">
    <li>
      <input type="radio" checked name="tabs" id="tab1">
      <label for="tab1">tab 1</label>
      <div id="tab-content1" class="tab-content animated fadeIn">
CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE 
CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE 
CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE 
      </div>
    </li>
    <li>
      <input type="radio" name="tabs" id="tab2">
      <label for="tab2">tab 2</label>
      <div id="tab-content2" class="tab-content animated fadeIn">
        CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE v CONTENT GOES HERE CONTENT GOES HERE
        CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE 
        CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE 
      </div>
    </li>
    <li>
      <input type="radio" name="tabs" id="tab3">
      <label for="tab3">tab 3</label>
      <div id="tab-content3" class="tab-content animated fadeIn">
        CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE v CONTENT GOES HERE CONTENT GOES HERE 
        CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE 
        CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE CONTENT GOES HERE 
      </div>
    </li>
</ul>

そして働くCSS：

.tabs input[type=radio] {
      position: absolute;
      top: -9999px;
      left: -9999px;
}
.tabs {
width: 980px;
float: none;  
list-style: none;
position: relative;
padding: 0;
margin: 20px auto;
}
  .tabs li{
    float: left;
  }
  .clearFix
{
clear: both;
} 
  .tabs label {
      display: block;
      padding: 10px 20px;
      border-radius: 2px 2px 0 0;
      color: #08C;
      background: rgba(255,255,255,0.2);
      cursor: pointer;
      position: relative;
      top: 3px;
      -webkit-transition: all 0.2s ease-in-out;
      -moz-transition: all 0.2s ease-in-out;
      -o-transition: all 0.2s ease-in-out;
      transition: all 0.2s ease-in-out;
  }
  .tabs label:hover {
    background: rgba(255,255,255);
    top: 0;
  }

  [id^=tab]:checked + label {
    background: #08C;
    color: white;
    top: 0;
  }

  [id^=tab]:checked ~ [id^=tab-content] {
      display: block;
  }
  .tab-content{
    display: none;
    text-align: left;
    width: 100%;
    font-size: 20px;
    line-height: 140%;
    padding-top: 10px;
    background: #08C;
    padding: 15px;
    color: #4a4949;
    position: absolute;
    top: 53px;
    left: 0;
    box-sizing: border-box;
    -webkit-animation-duration: 0.5s;
    -o-animation-duration: 0.5s;
    -moz-animation-duration: 0.5s;
    animation-duration: 0.5s;
  }

問題のある CSS ビット:

 .cont-wrapper{
    width: 980px;
    background: #82cff5;
    padding-right: 20px;
    padding-left: 20px;
overflow:hidden;
  }