.calculadora{
    max-width:700px;
    margin:50px auto;
    background:white;
    padding:30px;
    border-radius:15px;
    box-shadow:0 2px 12px rgba(0,0,0,.08);
}

.calculadora h1{
    text-align:center;
    margin-bottom:25px;
}

.form-group{
    margin-bottom:20px;
}

label{
    display:block;
    margin-bottom:8px;
    font-weight:bold;
}

input,
select{
    width:100%;
    padding:12px;
    border:1px solid #ddd;
    border-radius:8px;
    font-size:16px;
}

button{
    width:100%;
    padding:15px;
    border:none;
    border-radius:8px;
    background:#2563eb;
    color:white;
    font-size:18px;
    cursor:pointer;
}

button:hover{
    background:#1d4ed8;
}

.resultado{
    margin-top:30px;
    padding:20px;
    background:#f8fafc;
    border-radius:10px;
    display:none;
}

.resultado p{
    margin-bottom:10px;
    font-size:18px;
}
body{
    font-family:Arial,sans-serif;
    background:#f4f6f8;
    margin:0;
}

header{
    background:#2563eb;
    color:white;
    padding:30px;
    text-align:center;
}

main{
    max-width:1000px;
    margin:auto;
    padding:20px;
}

.card{
    background:white;
    padding:20px;
    margin-bottom:20px;
    border-radius:10px;
    box-shadow:0 2px 8px rgba(0,0,0,.1);
}

.card a{
    display:inline-block;
    margin-top:10px;
    background:#2563eb;
    color:white;
    text-decoration:none;
    padding:10px 15px;
    border-radius:6px;
}