body    {font-family: 'Arial', serif;}

h1      {color:royalblue;
        text-align: center;}

h2      {color:red;
        text-align:center;}

h3      {text-align: center;}

header {padding: 1em;
        background-color: thistle;
        margin-bottom:0.2em;}

header p {text-align: left;}

footer  {background-color: coral;
        padding:15px;
        text-align: center;}

ul      {margin:0;
        padding:15px;
        padding-left:20px;}

article {margin-bottom:0.2em;
        padding: 1em;
        background-color:moccasin;}

aside   {border:solid 1px black;
        width:30%;}

.nivel_1{padding:0px 0px 0px 0px;
        margin:0;
        font-family: monospace;}

.nivel_2{padding:0px 0px 0px 30px;
        margin:0;
        font-family: monospace;}

.nivel_3{padding:0px 0px 0px 60px;
        margin:0;
        font-family: monospace;}

.CodEjemplo{width:50%;
            margin-left:25%;
            background-color:white;}