/* Reset básico */
* { margin: 0; padding: 0; box-sizing: border-box; }

html, body {
    height: 100%;
    font-family: Arial, sans-serif;
    background: #f9f9f9;
    display: flex;
    flex-direction: column;
}

/* Header y menú */
header {
    background: #333;
    padding: 10px 0;
}
nav .menu {
    list-style: none;
    display: flex;
    justify-content: center;
    gap: 30px;
}
nav .menu a {
    color: white;
    text-decoration: none;
    font-weight: bold;
    font-size: 16px;
    transition: color 0.3s;
}
nav .menu a:hover, nav .menu a.active {
    color: #ff9800;
}

/* Contenido principal */
main {
    flex: 1;
    max-width: 900px;
    margin: 20px auto;
    padding: 20px;
}

/* Footer fijo abajo */
footer {
    background: #333;
    color: white;
    text-align: center;
    padding: 12px 0;
    font-size: 14px;
}