* {
    padding: 0;
    margin: 0;
    box-sizing: border-box;
  }
  
  html,body,main {
    height: 100%;
      width: 100%;
  }
  
  
  .left,.right{
    width: 50%;
    height: 100%;
    background-color:red;
    display: inline-block;
  }
  
  .right{
    background-color: blue;
   
  }