*{
    margin: 0;
    padding: 0;
    font-family: 'poppins', sans-serif;
    box-sizing: border-box;
}
.container{
    width: 100%;
    height: 70vh;
    background: #e3f9ff;
    display: flex;
    align-items: center;
    justify-content: center;
}

.heading {
    background: #e3f9ff;
    text-align: center;
    padding: 20px;
}

.calculator{
    background: #3b3e44;
    padding: 20px;
    border-radius: 10px;
}
.calculator form input{
    border: 0;
    outline: 0;
    width: 40px;
    height: 40px;
    border-radius: 10px;
    box-shadow: -8px -8px 15px rgba(255,255,255,0.1), -8px -8px 15px rgba(255,255,255,0.1);
    background: transparent;
    font-size: 15px;
    color: #fff;
    cursor: pointer;
    margin: 3px;
}

form .display{
    display: flex;
    justify-content: flex-end;
    margin: 20px 0px;
}

form .display input{
    text-align: right;
    flex: 1;
    font-size: 30px;
    box-shadow: none;
}

form input.equal{
    width: 90px;
}

form input.oprator{
    color: #ae9437;
}