修复列表绝对定位（由于z-index和位置，li被隐藏）

Question

问题是，当用户徘徊一个li时，它会使li的宽度达到屏幕的100％，所以li需要绝对定位来克服同一行上的另一个li，但是在这个列表中我想要6个或更多的孩子，当我添加其他li，它崩溃了。帮助

它必须如下所示（全屏50％宽度li）http://i.imgur.com/dRb92rK.gif

我想在一行中只有两个李。 （不是全部），5行（10行，每行2个......）

的jsfiddle：

https://jsfiddle.net/shotamickaia/pp658v6j/

$(function(){

  $('.leftchild').hover(function(){
    $('.left').css("z-index", "2");
    $('.left').css("width", "100%");
},function(){
    $('.left').css("z-index", "0");
    $('.left').css("width", "50%");
});

    $('.rightchild').hover(function(){
    $('.right').css("z-index", "2");
    $('.right').css("width", "100%");
},function(){
    $('.right').css("z-index", "0");
    $('.right').css("width", "50%");
});
function getCurrentScroll() {
    return window.pageYOffset;
    }
});

$(document).ready(function() {
  function setSettings() {
    windowWidth = $(window).width();
    windowHeight = $(window).height();
    width = (((50 * windowWidth) / 100)*50) / 100;
    marginleft = ((((50 * windowWidth) / 100)*50) / 100) / 2;
    margintop = (((50 * windowHeight) / 100)*50) / 100;
    numitems =  $(".slides li").length;
    var myheight = (numitems * 75);

    $('.leftchild').css('width', width);
    $('.leftchild').css('marginLeft',marginleft);
    $('.leftchild').css('marginTop',margintop);
    $('.rightchild').css('width', width);
    $('.rightchild').css('marginRight',marginleft);
    $('.rightchild').css('marginTop',margintop);
  };
  setSettings();
  
  $(window).resize(function() {
    setSettings();
  });
});

body,html {
	margin:0;
	padding:0;
	height:100%;
	background: white;
}

#reasons {
  width: 100%;
  float: left;
  margin: 0;
  height: auto;
  padding: 0;
  background: #f7f2ee;
}
.slides {
  list-style-type: none;
  padding: 0;
  width: 100%;
  height: 100%;
  position: relative;
  margin: 0;
}
.slides li {
  height: 100vh;
  width: 50%;
  background-repeat: no-repeat;
  background-position: center center;
  background-attachment: fixed;
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
  position: relative;
  float: left;
  transition: all .4s linear;
  position: absolute;
  width: 100%;
  z-index: 0;
}
.slides li:nth-child(even) {
  z-index: 1;
  background-attachment: cover;
  width: 50%;
  right: 0;
}
.slides li:nth-child(even) summary {
  width: 300px;
  margin-right: 200px;
  color: white;
  text-align: center;
  float: right;
}
.slides li:nth-child(3) {
  margin-top: 50%;
}
.slides li summary {
  color: white;
  float: left;
  text-align: center;
  cursor: default;
}
.slides li summary h2 {
  font-family: 'Proxima Nova Bold';
  font-size: 48px;
  text-transform: uppercase;
  letter-spacing: 20px;
  margin: 10% 0;
}
.slides li summary p {
  width: 100%;
  font-size: 16px;
  text-align: center;
  font-family: 'Andada';
  font-weight: normal;
  font-style: italic;
  opacity: 0.95;
  padding: 0;
  margin: 0;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<section id="reasons">
  <div class="slider">

    <ul class="slides">
      <li class="left" style="background-image: url(content/test1.jpg); background-color:black;">
        <summary class="leftchild">
          <h2>Test 1</h2>
          <p>Test description</p>
        </summary>
      </li>
      <li class="right" style="background-image: url(content/test2.jpg); background-color:red;">
        <summary class="rightchild">
          <h2>TEST 2</h2>
          <p>Test description</p>
        </summary>
      </li>

      <li class="left" style="background-image: url(content/test3.jpg); background-color:black;">
        <summary class="leftchild">
          <h2>Test 3</h2>
          <p>Test description</p>
        </summary>
      </li>
      <li class="right" style="background-image: url(content/test4.jpg); background-color:red;">
        <summary class="rightchild">
          <h2>TEST 4</h2>
          <p>Test description</p>
        </summary>
      </li>

      <li class="left" style="background-image: url(content/test5.jpg); background-color:black;">
        <summary class="leftchild">
          <h2>Test 5</h2>
          <p>Test description</p>
        </summary>
      </li>
      <li class="right" style="background-image: url(content/test6.jpg); background-color:red;">
        <summary class="rightchild">
          <h2>TEST 6</h2>
          <p>Test description</p>
        </summary>
      </li>

      <li class="left" style="background-image: url(content/test7.jpg); background-color:black;">
        <summary class="leftchild">
          <h2>Test 7</h2>
          <p>Test description</p>
        </summary>
      </li>
      <li class="right" style="background-image: url(content/test8.jpg); background-color:red;">
        <summary class="rightchild">
          <h2>TEST 8</h2>
          <p>Test description</p>
        </summary>
      </li>

      <li class="left" style="background-image: url(content/test9.jpg); background-color:black;">
        <summary class="leftchild">
          <h2>Test 9</h2>
          <p>Test description</p>
        </summary>
      </li>
      <li class="right" style="background-image: url(content/test10.jpg); background-color:red;">
        <summary class="rightchild">
          <h2>TEST 10</h2>
          <p>Test description</p>
        </summary>
      </li>

    </ul>




  </div>
</section>