body {
    background-color: #006699;
    margin: 0;
    padding: 0;
    font-family: Arial, Helvetica, sans-serif;
}

/* HEADER */
.header {
    background: #006699;
    padding: 10px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.header .logo img {
    max-height: 110px;
}

/* MENU */
.nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    gap: 15px;
}

.nav a {
    color: #FFF;
    text-decoration: none;
    font-weight: bold;
}

/* CONTENIDO */
.contenido {
    padding: 20px;
    color: #FFF;
}

.intro h1 {
    margin-top: 0;
}

/* GRID DE TARJETAS */
.grid {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    padding: 20px 0;
}

.card {
    background: #FFF;
    color: #000;
    padding: 15px;
    border-radius: 4px;
    width: calc(25% - 20px);
    box-sizing: border-box;
    text-align: center;
}

.card img {
    max-width: 100%;
}

/* FOOTER */
.footer {
    background: #006699;
    color: #FFF;
    text-align: center;
    padding: 20px;
    margin-top: 40px;
}

.copyright {
    color: #FFF !important;
}

.scroll-top {
    color: #FFF;
    text-decoration: none;
    font-size: 24px;
}