#marco{
       position: absolute;
       background-color:black;
       border: 12px dashed white;
       width: 350px;
       top: 50px;
       left: 50px;
       height: 400px;
}
   #pantalla{
       position: absolute;
       background-color: turquoise;
       border: 1px solid black;
       width: 245px;
       top: 50px;
       left: 50px;
       height: 60px;
  }
   #botones{
       position: absolute;
       width: 245px;
       top: 125px;
       left: 50px;
       background-color: grey;
  }       
   #botones-numeros{
       position: absolute;
       background-color: grey;
       width: 150px;
  }
  #botones-operaciones{ 
       position: absolute;
       background-color: grey;
       left: 150px;
   }
   
   
   
button{ 
     border: none; 
     color: black;
     padding: 10px 15px;
     text-align:center;
     display:inline-block;
     font-size: 16px;
     margin: 4px 2px;
     cursor:pointer;
   }
   
   h3{
       margin:4px 4px;
       text-align: right;
    
   }
   
   h5{
       text-align:center;  
    
   } 
   
 
   
   
   
   
    
 ♌️♎️