body {
  padding: 2em;
  box-sizing: border-box;
  font-family: Avenir, sans-serif;
background-color: #b7c3da;
}

#centrar {
            max-width: 600px;
           
            margin: 0 auto;
        }

header {
            margin: 0 auto;
          text-align: right
    
        }
img {
    position: absolute;
    top:4em;
    margin-top: 30px;
}

#imagen { margin-top: 30px;}



.box { 
  width: 350px;
  padding: 20px;
  position:relative;
  top:26em;
  left:7.5em;
  text-align: center; 
  margin: .5em;
}
.inner-content {
  background: #fff;
  padding: .75em;
}

.border-top, .border-bottom {
  width: 0%;
  height: 3px;
  background: #6886B6;
  position: absolute;
  transition: all .3s ease;
}

/* Changing the left/right zero point will change where the transition starts from */
.border-top { top: 0; left: 0; }
.border-bottom { bottom: 0; right: 0; }
.box:hover .border-top, 
.box:hover .border-bottom {
  width: 100%;
}

.border-right, .border-left {
  width: 3px;
  height: 0%;
  background: #6886B6;
  position: absolute;
  transition: all .3s ease .3s;
} 
/* a .3 second delay causes our right/left borders to draw after our top/bottom borders */


/* Changing the top/bottom zero point will change where the transition starts from */
.border-right { top: 0; right: 0; }
.border-left { bottom: 0; left: 0; }
.box:hover .border-right, 
.box:hover .border-left {
  height: 100%;
}

a {
    text-decoration:none;
    font-size: 1.2em;
    text-decoration-color: #273577;
    
}

a:link {
    text-decoration: none;
    font-size: 1.2em;
    text-decoration-color: #273577;
    color:#273577;
}

a:visited {
    text-decoration: none;
    font-size: 1.2em;
    text-decoration-color: #273577;
    color:#273577;
}

a:focus {
    text-decoration: none;
    font-size: 1.2em;
    text-decoration-color: #273577;
    color:red;
}

a:hover {
    text-decoration: none;
    font-size: 1.2em;
    text-decoration-color: #273577;
    color:red;
}

a:active {
    text-decoration: none;
    font-size: 1.2em;
    text-decoration-color: #273577;
    color:red;
}