body {
    background-color: #a6c7e4;
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
}
.encabezado {
    background-image: url("https://www.comunicare.es/wp-content/uploads/2021/10/diseno-web-marketing-digital-cordoba-4.jpg"); /* ruta de tu imagen */
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    height: 250px;
}
header {
    background: #262b2c;
    padding: 1em;
    text-align: center;
}
/* encabezado principal */
h1 {
    color: #1a237e;
    text-align: center;
    background-color: #bbdefb; 
    padding: 20px;
}

/* barra de navegación */
nav {
    background-color: #3949ab;
    padding: 10px;
    text-align: center;
}
nav a {
    color: white;
    margin: 0 15px;
    text-decoration: none;
    font-weight: bold;
}
nav a:hover {
    text-decoration: underline;
}

/* secciones de texto */
main {
    max-width: 800px;
    margin: 30px auto;
    padding: 20px;
    background: white;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

main img {
    display: block;
    margin: 20px auto;
    border-radius: 12px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.contenedor {
    text-align: center;
    display: flex;
    gap: 15px;  
}

footer {
    text-align: center;
    padding: 20px;
    color: #5686b6;
    background: #333;
    text-decoration: none;
    margin: 0.5px;
}
.collage {
  column-count: 4;        /* número de columnas */
  column-gap: 8px;       /* espacio entre columnas */
}

.collage img {
    width: 100%;
    margin-bottom: 10px;
    display: block;
    border-radius: 8px;
}

.contenedor img, 
.contenedor video {
    width: 300px;
    height: auto;
}