styles.css

*{
    box-sizing: border-box;
}

body {
    font-family: Arial, Helvetica, sans-serif;
    max-width: 800px;
    margin: 0 auto;
    padding: 1.5rem;
    text-align: center;
}

.instrucoes {
    font-size: 1rem;
    margin-bottom: 1rem;
    line-height: 1.5;
    text-align: justify;
}

#texto {
    font-size: 1.2rem;
    background-color: #f3f3f3;
    padding: 1.2rem;
    margin-bottom: 1rem;
    width: 100%;
}

#entrada {
    width: 100%;
    padding: .8rem;
    margin-bottom: 1rem;
}

#resultado {
    font-size: 1.2rem;
    margin-bottom: 1rem;
}

button {
    font-size: 1rem;
    padding: .6rem 1.2rem;
    background-color: #007bff;
    color: #fff;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: 0.3s;
}

button:hover {
    background-color: #0056b3;
}

#alternarTema {
    position: fixed;
    top: 10px;
    right: 10px;
}

/* Tema claro e escuro*/
.claro {
    background-color: #fff;
    color: #333;
}

.escuro {
    background-color: #333;
    color: #fff;
}

.escuro #texto {
    color: #333;
}