:root {
    --azul-madrid: #003399;
    --gris-madrid: #5A6770;
    --texto: #1a1a1a;
    --texto-secundario: #4a4a4a;
}

body {
    font-family: 'DM Sans', system-ui, -apple-system, sans-serif;
    margin: 0;
    color: var(--texto);
}

.banda {
    background: var(--azul-madrid);
    color: white;
    padding: 1rem;
}

.banda .nav-link {
    color: rgba(255, 255, 255, 0.85);
}

.banda .nav-link:hover,
.banda .nav-link:focus {
    color: #ffffff;
}

.contenedor {
    width: 100%;
    margin: auto;
    max-width: 1100px;
    padding: 0 1rem;
}

.marca__logo {
    height: 36px;
    width: auto;
}

/* ============= HERO ============= */
.hero {
    background: linear-gradient(135deg, #001a4d 0%, #003399 70%, #1a4dcc 100%);
    color: #ffffff;
    padding: 3rem 1rem;
}

.hero .container {
    max-width: 1100px;
}

.hero__logo {
    width: 100%;
    max-width: 240px;
    height: auto;
    border-radius: 0.75rem;
    box-shadow: 0 6px 24px rgba(0, 0, 0, 0.35);
}

.hero__heading {
    font-size: clamp(2.4rem, 5vw, 3.5rem);
    font-weight: 700;
    margin-bottom: 0.25rem;
    letter-spacing: 0.02em;
}

.hero__subheading {
    font-size: clamp(1.1rem, 2vw, 1.5rem);
    font-weight: 400;
    margin-bottom: 0.75rem;
    color: #cfe0ff;
}

.hero__byline {
    font-size: 1rem;
    color: #e7eefb;
    margin-bottom: 0;
    max-width: 60ch;
}

/* ============= GENERAL SECTIONS ============= */
main h2 {
    color: var(--azul-madrid);
    font-size: clamp(1.6rem, 2.5vw, 2rem);
    margin-bottom: 1rem;
    border-bottom: 3px solid var(--azul-madrid);
    padding-bottom: 0.4rem;
    display: inline-block;
}

main p {
    font-size: 1rem;
    line-height: 1.75;
    color: var(--texto-secundario);
    text-align: justify;
}

.section-intro {
    font-style: italic;
    color: #555;
    margin-bottom: 1.5rem;
}

/* ============= RESOURCE CARDS ============= */
.resource-card-wrap {
    display: flex;
}

.resource-card {
    border: 1px solid #dee2e6;
    border-radius: 0.75rem;
    padding: 1.25rem;
    background: #ffffff;
    display: flex;
    flex-direction: column;
    width: 100%;
    transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.resource-card:hover {
    box-shadow: 0 6px 18px rgba(0, 51, 153, 0.15);
    transform: translateY(-2px);
}

.resource-card__title {
    color: var(--azul-madrid);
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.resource-card__description {
    font-size: 0.95rem;
    color: var(--texto-secundario);
    flex-grow: 1;
    margin-bottom: 0.75rem;
    text-align: left;
}

.resource-card__meta {
    list-style: none;
    padding-left: 0;
    margin-bottom: 1rem;
    font-size: 0.875rem;
    color: #555;
}

.resource-card__meta li {
    margin-bottom: 0.2rem;
}

/* ============= DOCUMENTATION LINKS ============= */
.documentation__links {
    list-style: none;
    padding-left: 0;
    margin-top: 1rem;
}

.documentation__links li {
    padding: 0.5rem 0;
    border-bottom: 1px solid #eee;
}

.documentation__links li::before {
    content: '\f135';
    font-family: 'bootstrap-icons';
    color: var(--azul-madrid);
    margin-right: 0.5rem;
}

.documentation__links a {
    color: var(--azul-madrid);
    text-decoration: none;
}

.documentation__links a:hover {
    text-decoration: underline;
}

/* ============= CITE BLOCK ============= */
.cite-block {
    background: #f7f9fc;
    border-left: 4px solid var(--azul-madrid);
    border-radius: 0.25rem;
    padding: 1rem 1.25rem;
    margin-bottom: 1rem;
}

.cite-block__label {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--azul-madrid);
    margin-bottom: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.cite-block__preferred {
    font-size: 1rem;
    color: var(--texto);
    margin-bottom: 0;
    text-align: left;
}

.cite-block__doi code {
    background: #fff;
    padding: 0.25rem 0.5rem;
    border-radius: 0.25rem;
    border: 1px solid #d0d7e2;
    color: var(--azul-madrid);
    font-size: 0.95rem;
}

.cite-block__bibtex {
    background: #1e1e1e;
    color: #e6e6e6;
    padding: 1rem;
    border-radius: 0.5rem;
    font-size: 0.85rem;
    overflow-x: auto;
    margin-bottom: 0;
}

.cite-block__bibtex code {
    background: transparent;
    color: inherit;
    font-family: 'SF Mono', 'Menlo', 'Consolas', monospace;
    white-space: pre;
}

/* ============= BUTTONS ============= */
.btn-madrid {
    background-color: var(--azul-madrid);
    color: #fff;
    border: none;
    font-weight: 500;
    padding: 0.5rem 1.25rem;
    border-radius: 0.375rem;
    text-decoration: none;
    transition: background-color 0.15s ease;
}

.btn-madrid:hover,
.btn-madrid:focus {
    background-color: #002266;
    color: #fff;
}

.btn-madrid:focus-visible {
    outline: 3px solid #99b3ff;
    outline-offset: 2px;
}

.btn-madrid-outline {
    background-color: transparent;
    color: #ffffff;
    border: 1px solid #ffffff;
    font-weight: 500;
    padding: 0.5rem 1.25rem;
    border-radius: 0.375rem;
    text-decoration: none;
    transition: background-color 0.15s ease;
}

.btn-madrid-outline:hover,
.btn-madrid-outline:focus {
    background-color: rgba(255, 255, 255, 0.15);
    color: #ffffff;
}

/* ============= CONTACT ============= */
.contact-maintainer {
    background: #f7f9fc;
    padding: 0.75rem 1rem;
    border-radius: 0.25rem;
    border-left: 4px solid var(--azul-madrid);
}

/* ============= FOOTER ============= */
.pie {
    border-top: 4px solid var(--azul-madrid);
    padding: 1.5rem 1rem;
}

.pie__inner {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    color: #cfd5e0;
    font-size: 0.9rem;
}

.firma__isotipo {
    height: 36px;
    width: auto;
}

.pie__meta {
    display: flex;
    gap: 0.5rem;
    align-items: center;
}

.pie__sep {
    opacity: 0.5;
}

/* ============= RESPONSIVE ============= */
@media (max-width: 575.98px) {
    .hero {
        padding: 2rem 1rem;
    }
    .hero__logo {
        max-width: 180px;
    }
}