<div class="container" id="container">
  <div class="item">1</div>
  <div class="item">2</div>
  <div class="item">3</div>
  <div class="item">4</div>
  <div class="item">5</div>
  <div class="item">6</div>
  <div class="item">7</div>
  <div class="item">8</div>
</div>
<div class="controls">
  <input type="radio" name="flex-wrap" id="nowrap" 
         onclick="
                  var container=document.getElementById('container'); 
                  container.style.WebkitFlexWrap = 'nowrap' 
                  container.style.flexWrap = 'nowrap' 
                  " checked>
  <label for="nowrap">flex-wrap: nowrap;</label>
  <br>
  <input type="radio" name="flex-wrap" id="wrap" 
         onclick="
                  var container=document.getElementById('container'); 
                  container.style.WebkitFlexWrap = 'wrap' 
                  container.style.flexWrap = 'wrap' 
                  ">
  <label for="wrap">flex-wrap: wrap;</label>
  <br>
  <input type="radio" name="flex-wrap" id="wrap-reverse" 
         onclick="
                  var container=document.getElementById('container'); 
                  container.style.WebkitFlexWrap = 'wrap-reverse' 
                  container.style.flexWrap = 'wrap-reverse' 
                  ">
  <label for="wrap-reverse">flex-wrap: wrap-reverse;</label>
</div>
body {
  background-color: #F5F5F5;
  color: #555;
  font-size: 1.1em;
  font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
}

hr {
  margin: 50px 0;
}

.container {
  margin: 150px auto;
  max-width: 800px;
  padding: 20px;
  -webkit-display: -webkit-box;
  -webkit-display: -webkit-flex;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  background-color: #594255;
}

.item {
  background-color: #fff;
  width: 100px;
  height: 100px;
  margin: 2px;
  text-align: center;
  line-height: 100px;
  font-weight: bold;
  font-family: sans-serif;
  font-size: 7em;
  color: #594255;
}

.controls {
  background-color: white;
  width: 300px;
  padding: 20px;
  line-height: 150%;
  position: fixed;
  top: 0;
  right: 0;
  border: 1px solid #ddd;
}