#training-div { 
  overflow:auto; 
  width: 600px; 
  background: gray; 
} 

#training-left, #training-right { 
  width: 50%; 
  margin:5px; 
  padding: 1em; 
  background: white; 
} 

#training-left  { float:left;  }
#training-right { float:right; }