HTML/CSS file

<!Doctype html>

<head>

<style type="text/css">
body{
  margin:0;
  background-color: red;
}

#submenu{
height: 45px;
width: 100%;
background-color:green;
}

#navigation.fixed{
    position:fixed;
    background-color: blue;
    width:100%;
    top:0;
    height:45px;
    color:white;
    }


#navigation{
position:absolute;
background-color:blue;
width: 100%;
height: 45px;
color:white;
}

#nav-wrapper{
width: 1600px;
margin-left: 65px;
text-align: left;
}

#navigation ul{
list-style-type: none;
padding: 0;
margin: 0;
}

#navigation ul li{
display: inline-block;
color: green;

}

#navigation ul li:hover{
background-color: blue;
}

#navigation ul li a, visited{
display: block;
text-decoration: none;
}

#navigation ul li:activated{
border-top: 2px solid black;
}

#navigation li{
width: 180px;
text-align:center;
font-size: 20px;
height: 45px;
background-color:white;
}

li{
text-align:center;
}

/*#navigation a{
top: 10px;
color: green;
vertical-align: middle;
}*/

#navigation a{
color: green;
line-height: 45px;
}

header{
background-color:orange;
height: 80px;

    }
</style>

</head>


<body>
<nav id="navigation">
  <div id="nav-wrapper">

    <ul>
      <li>
      <a id="link1" href="">Startseite</a>
      </li>


      <li>
      <a id="link2" href="">laksdfjlas</a>
      </li>


      <li>
      <a id="link3" href="">lsadkfjask</a>
      </li>


      <li>
      <a id="link4" href="">askldfjasd</a>
      </li>


      <li>
      <a id="link5" href="">askldfjasd</a>
      </li>


    </ul>
  </div>
  </nav>
      <div id="dropdown1">erste dropdown!</div>
        <div id="dropdown2">zweites dropdown!</div>
              <div id="dropdown3">drittes dropdown!</div>
                <div id="dropdown4">viertes dropdown!</div>
                      <div id="dropdown5">fünftes dropdown!</div>
</body>

</html>