html {
    background-color: #e3fde4;
    align-content: center;
}

body {
    font-family: "Open Sans";
    font-size: 14px;
    line-height: 1.5em;
    color: #404040;
    background-color: #e3fde4;
    align-content: center
}


a {
    color: #0a5834;
    background-color: #ffffff;
    text-decoration: none;
}

a:hover {
    color: #50077e;
    background-color: #ffffff;
    border-bottom: 2px solid;
}

div.materias
{
    padding: 30px;
    border: 5px solid;
    height: 380px;
    width: 300px;
      margin-left: auto ;
  margin-right: auto ;
}