body{
    background:sky-blue;
  }
  .canvas{
    background-color:black;
    width:400px;
    margin:40px auto;
    border-radius:10px;
    padding:10px;
    padding-bottom:20px;
    box-shadow: inset 2px 2px 0px rgba(255,255,255,0.2), 1px 1px 0px rgba(255,255,255,0.5);
    
  }
  #screen{
    background-color:lightgreen;
    margin:20px 10px 20px 10px;
    padding:5px;
    padding-right:10px;
    text-align:right;
    min-height:45px;
    font-size:35px;
    box-shadow: inset 2px 2px 0px rgba(0,0,0,0.5), 1px 1px 0px rgba(255,255,255,0.5);
    font-family: 'VT323', monospace;
  }
  #screen{
    text-allign:right;
    border-radius : 3px;
  }
  button{
    width:65px;
    height:50px;
    background-color:lightgrey;
    border-radius:3px;
  }
  .line{
    padding-bottom:10px;
    padding-left:12.5px;
  }
  #clear{
    background-color:red;
    color:white;
    border:solid;
    border-width:2px;
    border-style:inset;
    border-color:black;
    border-top-color:rgba(255,150,150,.5);
    border-left-color:rgba(255,150,150,.5);
    border-bottom-style:solid;
    border-bottom-color:rgba(100,0,0);
    border-right-style:solid;
    border-right-color:rgba(100,0,0);
    
  }
  #clea{
    background-color:red;
    color:white;
    border:inset;
    border-color: rgba(50,50,50,0.5), 2px 1px 0px rgba(255,0,0,0.5);
    
    box-shadow: inset 1px 1px 0px rgba(100,100,100,0.5);
    -moz-box-shadow: inset 1px 1px 0px rgba(100,100,100,0.5);
  }