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<div class="container">

  <div class="element "></div>
  <div class="element "></div>
  <div class="element "></div>
  <div class="element "></div>
  
</div>

.container {
  width: 100%;
  background: #fff;
}
.container:after {
  display: block;
  width: 0;
  height: 0;
  content: '';
  clear:both;
}
.element {
    background-color: purple;
    float: left;
    margin-right: 10px;
    position: relative;
    width: 20vw;
    height: 15vw;
}