body{
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background: linear-gradient(to right, #667eea, #764ba2);
    font-family: Arial;
}

.calculator{
    background: #222;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 0 20px black;
    text-align: center;
}

input{
    width: 220px;
    height: 50px;
    margin-bottom: 15px;
    font-size: 20px;
    text-align: right;
    border: none;
    border-radius: 5px;
    padding: 5px;
}

button{
    width: 50px;
    height: 50px;
    margin: 5px;
    font-size: 18px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    background: #444;
    color: white;
}

button:hover{
    background: orange;
}