body{
    margin: 0;
    padding: 0;
    color: white;
    font-family: 'Montserrat', sans-serif;
    background-color: black;
}
h1{
    text-align: center;
    font-size: 3em;
}
.calc-box{
    text-align: center;
    padding: 2%;
    margin: 5% 10%;
    border-radius: 2%;
    background-color: #1b1a1a;
    
}
td{
    width: 40%;
}
p{
    font-size: 2.3em;
    text-align: center;
}
input, button{
    margin: 0.5em;
    padding: 0.5em;
    background-color: #1b1a1a;
    border: 1px solid white;
    color: white;
    font-family: 'Montserrat', sans-serif;
    font-size: 1rem;
}
.highlight-input{
    border: 1px solid red;
}
td>input{
    width: 80%;
}

button{
    width: 10em;  
}
.btn{
    text-align: center;
    justify-content: center;
}