body {
    margin: 0;
    background-color: #eeeeee;
}
/* Encabezado */
.main-header {
    background-color: #202f5b;
}
.top-bar-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.7em 3em;
    color: white;
}
.social-header a img{
    width: 2.5em;
}

.mid-bar-header {
    text-align: center;
    padding: 1em;
    background: url("./images/backgroundMiddle.jpg");
}

.topnav {
    margin: 0 0 0 3em;
    overflow: hidden;
}
.topnav a {
    float: left;
    display: block;
    color: #b1bcdf;
    text-align: center;
    padding: 14px 16px;
    text-decoration: none;
    font-family: 'Gill Sans', 'Gill Sans MT', Calibri, 'Trebuchet MS', sans-serif;
    font-weight: bold;
    font-size: 0.9em;
}
.topnav a:hover {
    background-color: #1151d3;
    color: white;
}
.topnav a.active {
    background-color: #1151d3;
}
.topnav .icon {
    display: none;
}
/* RWD */
@media screen and (max-width: 450px) {
    .top-bar-header {
        display: block;
        text-align: center;
    }
}
@media screen and (max-width: 550px) {
    .mid-bar-header img{
        width: 100%;
    }
}
@media screen and (max-width: 930px) {
    .topnav a:not(:first-child) {display: none;}
    .topnav a.icon {
      float: right;
      display: block;
    }
}
@media screen and (max-width: 930px) {
    .topnav.responsive {position: relative;}
    .topnav.responsive .icon {
      position: absolute;
      right: 0;
      top: 0;
    }
    .topnav.responsive a {
      float: none;
      display: block;
      text-align: left;
    }
}