en dan nog een text-align: left;
in de body
in de body

<html>
<head>
<style type="text/css">
body {
background-color: #CDC9C9;
padding: 0;
margin: 0;
}
p {
margin-left: 10px;
margin-right: 10px;
}
h1 {
margin-top: 15px;
margin-left: 15px;
margin-bottom: 10px;
}
#kolom_1 {
background-color: #4876FF;
color: #000000;
height: 198px;
width: 191px;
border: 1px solid #000000;
border-bottom: none;
float: left;
position: absolute;
top: 0;
left: 0;
}
#kolom_2 {
background-color: #4876FF;
color: #000000;
height: 369px;
width: 191px;
border: 1px solid #000000;
float: left;
position: absolute;
top: 198.5px;
left: 0;
}
#kolom_3 {
background-color: #4876FF;
color: #000000;
height: 301px;
width: 479px;
border-right: 1px solid #000000;
border-bottom: 1px solid #000000;
float: left;
position: absolute;
top: 266.9px;
left: 191px;
}
#kolom_4 {
background-color: 4876FF;
color: #000000;
height: 266px;
width: 479px;
border: 1px solid #000000;
border-left: none;
float: left;
position: absolute;
top: 0;
left: 191px;
}
#kolom_5 {
background-color: 4876FF;
color: #000000;
height: 567px;
width: 287.5px;
border: 1px solid #000000;
border-left: none;
float: left;
position: absolute;
top: 0;
left: 670px;
}
</style>
<title>Homepagina</title>
</head>
<body>
<div id="kolom_1">
</div>
<div id="kolom_2">
</div>
<div id="kolom_3">
</div>
<div id="kolom_4">
</div>
<div id="kolom_5">
</div>
</body>
</html> 
<html>
<head>
<style type="text/css">
body {
background-color: #CDC9C9;
padding: 0;
margin: 0;
}
p {
margin-left: 10px;
margin-right: 10px;
}
h1 {
margin-top: 15px;
margin-left: 15px;
margin-bottom: 10px;
}
div#container{
width: 900px;//Breedte van je layout.
margin: 0px auto;
}
#kolom_1 {
background-color: #4876FF;
color: #000000;
height: 198px;
width: 191px;
border: 1px solid #000000;
border-bottom: none;
float: left;
position: absolute;
top: 0;
left: 0;
}
#kolom_2 {
background-color: #4876FF;
color: #000000;
height: 369px;
width: 191px;
border: 1px solid #000000;
float: left;
position: absolute;
top: 198.5px;
left: 0;
}
#kolom_3 {
background-color: #4876FF;
color: #000000;
height: 301px;
width: 479px;
border-right: 1px solid #000000;
border-bottom: 1px solid #000000;
float: left;
position: absolute;
top: 266.9px;
left: 191px;
}
#kolom_4 {
background-color: 4876FF;
color: #000000;
height: 266px;
width: 479px;
border: 1px solid #000000;
border-left: none;
float: left;
position: absolute;
top: 0;
left: 191px;
}
#kolom_5 {
background-color: 4876FF;
color: #000000;
height: 567px;
width: 287.5px;
border: 1px solid #000000;
border-left: none;
float: left;
position: absolute;
top: 0;
left: 670px;
}
</style>
<title>Homepagina</title>
</head>
<body>
<div id="container">
<div id="kolom_1">
</div>
<div id="kolom_2">
</div>
<div id="kolom_3">
</div>
<div id="kolom_4">
</div>
<div id="kolom_5">
</div>
</div>
</body>
</html>
zo moet ie lukken, alleen de breedte van je lay ff aanpassen in de code!
Zeg zo wel of het gelukt is,




