*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body{
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background: #E9E3DF;
}
.calculator{
    background:#113F67;
    padding: 20px;
    width: 300px;
}
.display{
    padding: 15px;
    min-height: 50px;
    text-align: right;
    border: 2px solid;
    margin-bottom: 15px;
    background: white;
    /*color: #0f0;*/
}
.buttons {
    display: grid;
    grid-template-columns: repeat(4,1fr);
    gap: 10px;
}
button.btn{
    padding: 20px;
    font-size: 1.2rem;
    border: none;
    border-radius:5px ;
    cursor: pointer;
}
button.equal{
    grid-column: span 4;
}