*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body{
    background-color: #f2f2f2;
    font-family: Arial, Helvetica, sans-serif;
}

.cauculator{
    background-color: #fff;
    border-radius: 10px;
    box-shadow: 0 2px 5px rgba(0 , 0, 0, 0.3);
    margin: 3rem auto;
    max-width: 500px;
    padding: 1.6rem;
}
h2{
    text-align: center;

}
label{
    display: block;
    font-weight: bold;
    margin: .5rem 0;
}
input, select{
    border: 1px solid #ccc;
    border-radius: 4px;
    box-sizing: border-box;
    margin-bottom: .6rem;
    padding: .6rem;
    width: 100%;
}
button{
    background-color: #4caf50;
    border: none;
    border-radius: 4px;
    color: #fff;
    cursor: pointer;
   font-size: 1rem;
   margin-bottom: 10px;
   padding: .8rem;
   width: 100%;
   transform: .4s;
}
button:hover{
    background-color: #3e8e41;

}
input:disabled{
    background-color: #f2f2f2;
    color: #777;
}