*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    color: white;
}
body {
    height: 100vh;
    width: 100vw;
    display: flex;
    background-color: rgba(21, 128, 116, 0.77);
    align-items: center;
    justify-content: center;
}
.calBox {
    width: 300px;
    border: none;
    border-radius: 10px;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 10px;
    background-color: rgb(255, 255, 255);
    box-shadow: 0px 4px 20px rgb(52, 52, 52);
    height: 570px;
}
.display {
    width: 98%;
    height: 60px;
    margin-bottom: 15px;
    margin-top: 20px;
    outline: none;
    border-radius: 5px;
    background-color: rgba(21, 128, 116, 0.514);
    border: none;
    box-shadow: 0px 0px 5px rgba(143, 143, 143, 0.692);
    font-size: 30px;
}
.buttons {
    width: 80%;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 10px;
}
.btn {
    flex-basis: 30%;
    height: 65px;
    font-size: 20px;
    font-weight: bold;
    background-color: rgb(35, 35, 35);
    border: none;
    box-shadow: 2px 4px 5px rgba(0, 0, 0, 0.599);
    border-radius: 10%;
}
.op {
    background-color: rgb(46, 115, 255);
}