Hier ein Beispiel wie man Flexbox Layout umsetzten kann
Code
<!DOCTYPE html>
<html lang="de">
<head>
<meta charset="UTF-8">
<title>Flexboxen -Layout</title>
<style>
#headerlinks,#headermitte,#headerrechts{
flex:1;
border:1px solid red;
}
#suche{
margin-top:20px;
height:30px;
width:200px;
font-size:26px;
}
*{
margin: 0px;
padding: 0px;
}
body{
background: #E6E6E6;
border: solid 3px black;
display:flex;
flex-direction:column;
}
p {
font-family: Helvetica, Avenir, Arial, sans-serif;
font-size: 11px;
}
header{
width: 100%;
background: #ABABAB;
border: solid 2px blue;
text-align:center;
display:flex;
}
header p{
font-size:30px;
}
#wrapper{
display:flex;
}
#left{
flex:1;
padding-top:30px;
border: dotted 2px black;
background: #D4D4D4;
text-align:center;
}
main{
flex:4;
border: solid 2px blue;
background: #D1EEEE;
}
main p{
font-size:100px;
text-align:center;
}
#right{
flex:1;
background: white;
border: dotted 2px black;
background: lightgreen;
text-align:center;
padding-top:30px;
}
ul {
list-style-type: none;
list-style-position: inside;
font-family: Helvetiva, Avenir, Arial sans-serif;
font-size: 12px;
margin-left: 0em;
padding-left: 0em;
}
footer{
background: #ABABAB;
border: solid 2px blue;
text-align:center;
}
footer p{
font-size:30px;
}
</style>
</head>
<body>
<header>
<div id="headerlinks">
</div>
<div id="headermitte">
<p> header </p>
</div>
<div id="headerrechts">
<input type="text" id="suche" placeholder="suche..">
</div>
</header>
<div id="wrapper">
<aside id="left">
<ul>
<li> <p>Navigation 1</p> </li>
<li> <p>Navigation 2</p> </li>
<li> <p>Navigation 3</p> </li>
</ul>
</aside>
<main>
<p>Mitte</p>
</main>
<aside id="right">
<br />
</aside>
</div>
<footer> <p> Fußzeile </p></footer>
</body>
</html>