*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: Arial, Helvetica, sans-serif;
}

body{
    background-color: #f4f4f4;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
}

.container{
    background-color: #fff;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.2);
    padding: 1.5rem;
    width: 400px;
}
h1{
    font-size: 24px;
    margin-bottom: 1.5rem;
    text-align: center;
}
.input-group{
    display: flex;
    flex-direction: column;
    margin-bottom: 1.2rem;
}
.input-group label,
.output-group label{
   margin-bottom: .4rem;
   font-weight: bold;
}
select,
input{
    padding: .8rem;
    border-radius: 5px;
    border: none;
    font-size: 1rem;
    background-color: #EEE;
}

button{
    background-color: #4caf50;
    border-radius: 5px;
    border: none;
    color: #fff;
    cursor: pointer;
    font-size: 1rem;
    padding: .8rem 1.2rem;
    opacity: .7;
    transition: .4s;
}
button:hover{
    opacity: 1;
}
.output-group{
    display: flex;
    flex-direction: column;
    margin-top: 1.2rem;
}
#message{
    font-size: .8rem;
    color: #4caf50;
    margin-top: 0.7rem;
    text-align: center;
}