*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: Arial, sans-serif;
}
h1{
   
    color: #fff;
    margin:  0;
    text-align: center ;

}
.container{
    height: 90vh;
    width: 100%;
    background-color: #212324;
    display: grid;
    align-items: center;
    justify-content: center;
}
.calculator{
    background: #000307;
    padding: 10px;
    border-radius: 10px;

}
.calculator form input{
    border:0;
    outline:0;
    width: 60px;
    height: 60px;
    border-radius: 10px;
    box-shadow: -8px -8px 15px  rgba(255,255,255,0.1),5px 5px 15px  rgba(0,0,0,0.2);
    background: transparent;
    font-size: 20px;
    color:#fff;
    cursor: pointer;
    margin: 10px;

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

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

}
form input.equal{
    width: 145px;

}
footer{
    position: absolute;
    bottom: 0;
    width: 100%;
    text-align: center;
    padding: 20px;
    background: #212324;
    color: #fff;
    font-size: 20px;
}
footer a{
    color: #fff;
    text-decoration: none;
}
footer a:hover{
    color: rgb(38, 190, 190);
    text-decoration: underline;
}
footer p span{
    color: red;
}