* {
    margin: 0;
    padding: 0;
    -webkit-box-sizing: border-box;
            box-sizing: border-box;
    font-family: 'Roboto', sans-serif;
}

.app {
    width: 100%;
    height: 100vh;
    background: #d8fbf5;
    display: -webkit-box;
    display: -ms-flexbox;
    display: flex;
    -webkit-box-align: center;
        -ms-flex-align: center;
            align-items: center;
    -webkit-box-pack: center;
        -ms-flex-pack: center;
            justify-content: center;
}

.calculator {
    background: #3a4453;
    padding: 20px;
    border-radius: 10px;
}

.calculator form input {
    border: 0;
    outline: 0;
    width: 60px;
    height: 60px;
    border-radius: 10px;
    -webkit-box-shadow: -8px -8px 15px rgb(25 143 72 / 10%), 5px 5px 10px rgb(11 29 62 / 20%);
            box-shadow: -8px -8px 15px rgb(25 143 72 / 10%), 5px 5px 10px rgb(11 29 62 / 20%);
    background: transparent;
    font-size: 20px;
    color: #fff;
    cursor: pointer;
    margin: 10px;
}

form .display {
    display: -webkit-box;
    display: -ms-flexbox;
    display: flex;
    -webkit-box-pack: end;
        -ms-flex-pack: end;
            justify-content: flex-end;
    margin: 20px 0;
}

form .display input {
    text-align: right;
    -webkit-box-flex: 1;
        -ms-flex: 1;
            flex: 1;
    font-size: 45px;
    -webkit-box-shadow: none;
            box-shadow: none;
}

form input.equel {
    width: 145px;
}

form input.oprator {
    color: #33c76e;
}