1.css

body{

  text-align : center;
  
  background-color: rgb(239, 243, 247);

  font-family: Monospace;
 
}

.green{

   
    margin: 10px;
    height:100px;
    width:100px;
    background:rgb(133, 235, 133);
    display: flex;
    
}

.blue{

    
    margin: 10px;
    height:100px;
    width:100px;
    background:rgb(90, 79, 239);
    display: flex;
    
}


.red{

    
    margin: 10px;
    height:100px;
    width:100px;
    background:rgb(225, 70, 70);
    display: flex;
    
}

.yellow{

    
    margin: 10px;
    height:100px;
    width:100px;
    background-color:rgb(221, 234, 111);
    display: flex;
    
}

.box1{

display: flex;
justify-content: center;
}
.box2{

display: flex;

justify-content: center;
}

.start{

    font-family: 'Franklin Gothic Medium', 'Arial Narrow', Arial, sans-serif;
}

button{

    font-family: sans-serif ;
}