<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>Simple clearing example</title>
    <style>
      body {
        width: 90%;
        max-width: 900px;
        margin: 0 auto;
        font: .9em/1.2 Arial, Helvetica, sans-serif;
      }

      .box {
        float: left;
        margin-right: 15px;
        width: 150px;
        height: 150px;
        border-radius: 5px;
        background-color: rgb(207,232,220);
        color: #000;
        padding: 1em;
      } 

      .wrapper {
    