.arb_layout {
    --arb-accent: #0074C8;
    --arb-accent-soft: rgba(0, 116, 200, 0.08);
    --arb-text: #1f2937;
    --arb-text-muted: #6b7280;
    --arb-border: #e9ebef;

    padding: 50px 0;
}

/* ---------- Sidebar / arbolado ---------- */

.arb_sidebar {
    display: block;
    background-color: #fff;
    border: 1px solid var(--arb-border);
    border-radius: 18px;
    padding: 1.75rem 1.5rem;
    box-shadow: 0 12px 30px -18px rgba(15, 23, 42, 0.18);
}

@media (min-width: 992px) {
    .arb_sidebar {
        position: sticky;
        top: 110px;
    }
}

/*.arb_grupo {
    margin-bottom: 1.6rem;
}*/

.arb_grupo:last-child {
    margin-bottom: 0;
}

.arb_grupo_titulo {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.72rem;
    font-weight: 700;
    letter-spacing: 0.09em;
    text-transform: uppercase;
    color: var(--arb-text-muted);
    text-decoration: none;
    margin-bottom: 0.85rem;
}

.arb_grupo_titulo::before {
    content: "";
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--arb-accent);
    opacity: 0.55;
    flex: none;
    transition: opacity 0.15s ease, transform 0.15s ease;
}

a.arb_grupo_titulo:hover,
a.arb_grupo_titulo.active {
    color: var(--arb-accent);
}

a.arb_grupo_titulo.active::before {
    opacity: 1;
    transform: scale(1.15);
}

.arb_lista {
    list-style: none;
    margin: 0;
    padding: 0;
    border-left: 2px solid var(--arb-border);
}

.arb_lista .arb_lista {
    margin-left: 1rem;
    margin-top: 0.15rem;
    margin-bottom: 0.35rem;
}

.arb_item {
    position: relative;
}

.arb_item > a,
.arb_item > span {
    display: block;
    margin-left: -2px;
    padding: 0.5rem 0.75rem 0.5rem 1.1rem;
    border-left: 2px solid transparent;
    border-radius: 0 10px 10px 0;
    font-size: 0.925rem;
    line-height: 1.35;
    color: var(--arb-text);
    text-decoration: none;
    transition: background-color 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.arb_item > span {
    color: var(--arb-text-muted);
}

.arb_item > a:hover {
    background-color: var(--arb-accent-soft);
    color: var(--arb-accent);
}

.arb_item.active > a {
    background-color: var(--arb-accent-soft);
    border-left-color: var(--arb-accent);
    color: var(--arb-accent);
    font-weight: 600;
}

/* ---------- Columna de contenido ---------- */

.arb_contenido {
    color: var(--arb-text);
}

.arb_contenido h1,
.arb_contenido h2,
.arb_contenido h3 {
    color: #111827;
}

.arb_contenido h1 {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 0.35rem;
}

.arb_contenido h2 {
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--arb-accent);
    margin-bottom: 1.25rem;
}

.arb_contenido p {
    color: #374151;
    line-height: 1.7;
    margin-bottom: 1.1rem;
}

.arb_meta {
    font-size: 0.85rem;
    color: var(--arb-text-muted);
    margin-bottom: 0.5rem;
}

.arb_imagen_ficha {
    border-radius: 12px;
    margin-bottom: 1.25rem;
}