<style>
.container {
  font-size: 50px;
  font-family: Ahem;
  color: green;
}
.narrowfloat { 
  background-color: blue;
  float: left;
  width: 10px;
  height: 30px; 
}
.widefloat {
  background-color: blue;
  float: left;
  clear: left; 
  width: 50px;
  height: 20px;
}
</style>
<div class="container"><div class="narrowfloat"></div><div class="widefloat"></div>X</div>