/* Estilos básicos */
body {
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 20px;
    background-color: #f5f5f5;
    color: #333;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background: #fff;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

h1 {
    color: #2c3e50;
    text-align: center;
    margin-bottom: 30px;
}

/* Estilos del formulario */
.factura-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

fieldset {
    border: 1px solid #ddd;
    border-radius: 5px;
    padding: 15px;
}

legend {
    padding: 0 10px;
    font-weight: bold;
    color: #2c3e50;
}

.form-group {
    margin-bottom: 15px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: 600;
}

input[type="text"],
input[type="email"],
input[type="number"] {
    width: 100%;
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
    box-sizing: border-box;
}

input[readonly] {
    background-color: #f0f0f0;
}

/* Botón */
.btn-generar {
    background-color: #3498db;
    color: white;
    border: none;
    padding: 10px 15px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 16px;
    transition: background-color 0.3s;
}

.btn-generar:hover {
    background-color: #2980b9;
}

/* Responsive */
@media (max-width: 600px) {
    .container {
        padding: 15px;
    }
}