/* Stylesheet für Übungsseiten "Little Boxes, Teil 1" */
 * { padding: 0; margin: 0; }
 html { height: 100%; margin-bottom: 1px; }
 body {
   background-color: #F2F2F2;
   color: black;
   font-family: Verdana, Arial, Helvetica, sans-serif;
   font-size: small;
 }

body {
  padding: 10em 0 6em;
}
 
body,
.wrapper {
  margin: 10px auto;
  max-width: 120em;	
}

header {
  position: fixed;
  top: 0;
  left: 0; 
  right: 0;
  background-color: white;
}

nav {
  position: fixed;
  padding: 10px;
  top: 7em;
  left: 0;
  right: 0;
  background-color: white;
  color: #B97A57;
}

footer {
  position: fixed;
  padding: 10px;
  bottom: 0;
  left: 0;
  right: 0;
  background-color: white;
  color: #B97A57;
}

 h1 { font-size: 150%; }
 h2 { font-size: 130%; }
 h3 { font-size: 130%; }

 a:link { color: #B97A57; text-decoration: none; }
 a:visited { color: #B97A57; text-decoration: none; }
 a:hover, a:focus {
   border-bottom: 1px solid #000000; text-decoration: none;
 }
 a:active {
   background-color: #000000;
   color: white; text-decoration: none;
 }

 /* Abstand nach unten */
 h2, p, ul, ol { margin-bottom: 1em ; }

 /* Abstand nach unten */
 h1 { margin-bottom: 3em ; }

 /* Abstand nach oben */
 h2 { margin-top: 2em ; }

 /* Verschachtelte Listen ohne Abstand */
 ul ul { margin-bottom: 0; }

 /* Abstand von links */
 li { margin-left: 1em; }

 /* links-ausrichten */
  .links {
display: block;
width:100%;
text-align: left;
}

 /* zentrieren */
  .imgzentriert {
display: block;
width:100%;
text-align: center;
}

 /* rechts-ausrichten */
  .rechts {
display: block;
width:100%;
text-align: right;
}

<hr style="border:solid #00ffff 3px;
background-color:#0000ff;height:10px;width:400px;
text-align:center;">