JSFiddle - React, Tailwind, and code Playground

HTML

<div id="maincontent">

<!-- Dropdown-Menue -->
<div class="accordion">
<div class="single-accordion1">

<h2>Menü</h2>
	<!-- 1 -->
	<a href="#content1" style="text-decoration: none;">
  Inhalt1</a>

	<br>

	<!-- 2 -->
	<a href="#content2" style="text-decoration: none;">
	Inhalt2</a>
</div>
</div>

<section id="content">

<!-- Inhalt1 -->
    <div id="content1" class="content">
<img src="http://cdn.wonderfulengineering.com/wp-content/uploads/2014/09/blue-wallpaper-7.jpg" width="490px" height="450px">

    <div class="area" id="area1-1">
        <ul class="menu" id="menu1-1">
             <li><a href="http://www.google.de">LINK1.1</a></li>
        </ul>
    </div>
    <div class="area" id="area1-2">
        <ul class="menu" id="menu1-2">
             <li><a href="http://www.google.de">LINK1.2</a></li>
        </ul>
    </div>
    <div class="area" id="area1-3">
        <ul class="menu" id="menu1-3">
             <li><a href="http://www.google.de">LINK1.3</a></li>
        </ul>
    </div>
    <div class="area" id="area1-4">
        <ul class="menu" id="menu1-4">
             <li><a href="http://www.google.de">LINK1.4</a></li>
        </ul>
    </div>
    <div class="area" id="area1-5">
        <ul class="menu" id="menu1-5">
             <li><a href="http://www.google.de">LINK1.5</a></li>
        </ul>
    </div>
    </div>

<!-- Inhalt2 -->
    <div id="content2" class="content">
<img src="http://cdn.wonderfulengineering.com/wp-content/uploads/2014/09/Green-Wallpaper-11.jpg" width="490px" height="450px">

    <div class="area" id="area2-1">
        <ul class="menu" id="menu2-1">
             <li><a href="http://www.google.de">LINK2.1</a></li>
        </ul>
    </div>
    <div class="area" id="area2-2">
        <ul class="menu" id="menu2-2">
             <li><a href="http://www.google.de">LINK2.2</a></li>
        </ul>
    </div>
    <div class="area" id="area2-3">
        <ul class="menu" id="menu2-3">
             <li><a...

CSS

body {
background-color:#00538c;
}

#maincontent {
background-color: #fff;
width: 800px;
height: 550px;
position: relative;
margin-left: auto;
margin-right: auto;
margin-top: auto;
border: 1px solid;
border-color: #ffffff;
border-radius: 30px;
}
	
/* Navigation */
.accordion {
width: 400px;
padding: 3px;
position: relative;
margin-left:15px;
margin-top: 30px;
z-index: 2;
}

.single-accordion1 {
height: 55px;
width: 75px;
overflow: hidden;
background: #dddddd;
padding: 0px 20px;
-webkit-transition: all 0.2s; /* Safari */
transition: all 0.2s;
}

.single-accordion1:hover {				
height: 150px;			
width: 100px;			
border-radius: 30px;				
background: #a5e0ff;				
-webkit-transition: all 0.2s; /* Safari */				
transition: all 0.2s;		
}
		
.single-accordion1 h2:hover{				
cursor: pointer;			
}
				
.single-accordion1 h2{				
color: #00a0f5;				
font-size: 30px;				
line-height: 10px;			
}

.single-accordion1 h3{				
color: #000000;				
font-size: 20px;				
line-height: 20px;			
}
					
.single-accordion1 p {				
line-height: 10px;				
vertical-align: middle;				
color: #333;				
font-family: Verdana;				
font-size: 18px;				
text-align: left;	
padding: -30px;			
}

/* unvisited link */
a:link {
color: red;    
text-decoration: none;
}

/* visited link */
a:visited {   
color: red;    
text-decoration: none;
}

/* mouse over link */
a:hover {    
color: white;    
text-decoration: none;
}

/* selected link */
a:active {   
color: white;   
text-decoration: none;
}

/*----------------------------------------------------*/

#content {
    width: 600px;
    height: 520px;
    background-color: #ccc;
    -webkit-border-radius: 30px;
    -moz-border-radius: 30px;
    border-radius: 30px;
    font-family: Verdana;				
	  font-size: 20px;
    position: absolute; bottom: 18px; right: 10px;
}

#content > div {
    padding: 10px;
    display: none;
}

#content div:target {
    display: block;
    position: relative;
}

#content1 {
    width: 490px;
    height: 490px;
	  border:...