body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    background-color: darkslategray;
}
/* -------------- */
.logo {
    margin-left: 15px;
    font-size: 20px;
}
.contenedor-menu {
    background-color: rgba(80,85,223);
    color: white;
    height: 66px;
    display: flex;
    justify-content: space-between;
}
.lista-menu {
    display: flex;
}
ul li {
    list-style: none;
    margin-right: 15px;
    float: left;
}
header a{
    text-decoration: none;
    color: white
}

/* ------------- */

.publicacion {
    text-align: center;
}
.contenido {
    margin: 20%;
    margin-top: 10px;
    margin-bottom: 10px;
    box-shadow: 1px 1px 14px #ccc;
    background-color: rgba(189, 183, 107, 0.466);
    color: white;
}
img {
    width: 50%;
}

/* ------------ */

@media (min-width: 320px) and 
(max-width: 650px) {
    body {
        background-color: rgb(250, 247, 209);
    }
    strong {
        color: red;
    }
    .contenido {
        text-align: center;
        box-shadow: 1px 1px 14px #ccc;
        color: black;
        width: 80%;
        margin: 10%;
        margin-top: 10px;
    }
}