/* === Variables de colores === */
:root {
    --bg-color: #f4f4f9;
    --text-color: #333;
    --header-footer-bg: #004377;
    --header-footer-text: #fff;
    --card-back-bg: #009EE3;
    --link-bg: rgba(0, 0, 0, 0.3);
    --link-hover-bg: rgba(0, 0, 0, 0.6);
}

/* === Reset y base === */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: "Roboto", sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

header, footer {
    background-color: var(--header-footer-bg);
    color: var(--header-footer-text);
    padding: 1rem;
    text-align: center;
}

header h1 {
    font-size: 2.5rem;
    margin: 0;
    padding: 10px;
}


footer {
    margin-top: auto;
    font-size: .9rem;
    font-weight: bold;
}

footer .social-icons {
    margin-top: 0.5rem;
}

footer .social-icons a {
    color: #fff;
    margin: 0 8px;
    font-size: 1.4rem;
    display: inline-block;
    transition: color 0.3s ease, transform 0.3s ease;
}

footer .social-icons a:hover {
    color: #ffcc00;
    transform: scale(1.2);
}

/* === Grid === */
.grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 20px;
    padding: 20px;
}

/* === Card Flip === */
.card {
    perspective: 1000px;
}

.card-inner {
    position: relative;
    width: 100%;
    padding-top: 56.25%; /* 16:9 Aspect Ratio */
    transform-style: preserve-3d;
    transition: transform 0.8s cubic-bezier(0.4, 0.2, 0.2, 1), box-shadow 0.5s ease;
}

.card:hover .card-inner,
.card:focus-within .card-inner {
    transform: rotateY(180deg) scale(1.03);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.4);
}

.card-front, .card-back {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
    transition: transform 0.8s cubic-bezier(0.4, 0.2, 0.2, 1);
}

.card-front img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    transition: transform 0.5s ease;
}

.card:hover .card-front img,
.card:focus-within .card-front img {
    transform: scale(1.1);
}

.card-back {
    background-color: var(--card-back-bg);
    color: #fff;
    display: flex;
    justify-content: center;
    align-items: center;
    transform: rotateY(180deg);
    transition: background-color 0.5s ease;
}

.card-back a {
    color: #fff;
    text-decoration: none;
    font-size: 1.2rem;
    background-color: var(--link-bg);
    padding: 10px 20px;
    border-radius: 8px;
    transition: background-color 0.3s ease;
}

.card-back a:hover,
.card-back a:focus {
    background-color: var(--link-hover-bg);
}

/* ... otras reglas CSS ... */

/* --- Media queries para pantallas pequeñas --- */
@media (max-width: 600px) {
    header h1 {
        font-size: 1.6rem; /* Más pequeño en móviles */
    }
    footer {
        font-size: .6rem; /* Más pequeño en móviles */
    }
}