/* ==========================================================================
   Estilos Globales y Base
   ========================================================================== */
body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f7fafc;
    margin: 0;
    padding: 0;
    color: #2d3748;
}

/* Cabecera Moderna */
header {
    background-color: #1a365d;
    color: white;
    text-align: center;
    padding: 3rem 1rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
}

header .logo-header {
    max-width: 150px;
    height: auto;
    margin-bottom: 1rem;
}

header h1 {
    margin: 0;
    font-size: 2.3rem;
    letter-spacing: 0.5px;
}

header p {
    margin: 0.5rem 0 0 0;
    font-size: 1.1rem;
    opacity: 0.9;
}

/* Contenedor Principal */
.container {
    max-width: 1100px;
    margin: 3rem auto;
    padding: 0 1.5rem;
}

.seccion-titulo {
    text-align: center;
    margin-bottom: 3rem;
}

.seccion-titulo h2 {
    font-size: 1.8rem;
    color: #1a365d;
    margin-bottom: 0.5rem;
}

.seccion-titulo p {
    color: #718096;
    margin: 0;
}

/* ==========================================================================
   Cuadrícula de Anuncios y Tarjetas
   ========================================================================== */
.grid-anuncios {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2.5rem;
}

.tarjeta-ads {
    background-color: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.05), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    display: flex;
    flex-direction: column;
}

.tarjeta-ads:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

.tarjeta-ads img {
    width: 100%;
    height: 240px;
    object-fit: cover;
    background-color: #edf2f7;
}

/* Contenido Interno de la Tarjeta */
.contenido-ads {
    padding: 1.8rem;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.contenido-ads h3 {
    margin: 0 0 0.75rem 0;
    color: #2b6cb0;
    font-size: 1.3rem;
}

.contenido-ads p {
    font-size: 0.95rem;
    color: #4a5568;
    line-height: 1.5;
    margin: 0 0 1.5rem 0;
    flex-grow: 1;
}

/* Botón de Acción */
.btn-ver {
    display: inline-block;
    text-align: center;
    background-color: #3182ce;
    color: white;
    text-decoration: none;
    padding: 0.75rem 1.5rem;
    border-radius: 6px;
    font-size: 0.95rem;
    font-weight: bold;
    transition: background-color 0.2s;
}

.btn-ver:hover {
    background-color: #2b6cb0;
}

/* Pie de Página */
footer {
    text-align: center;
    padding: 2rem;
    color: #a0aec0;
    font-size: 0.85rem;
    margin-top: 5rem;
    border-top: 1px solid #e2e8f0;
}