Simple 2 column CSS layout
This is a tutorial on how to use CSS to create a simple two column layout. If you want to create a three column layout, read on as this tutorial explains a basic concept that can be used to create as many columns as you need.The layout consists of a header, a horizontal navigation bar, a main content column, a sidebar, and a footer. It is also horizontally centered in the browser window. A pretty basic layout, and not at all difficult to create with CSS once you know how to deal with the inevitable Internet Explorer bugs.
To see the full CSS used for each step, view source on the example documents.
1. Basic structure
First of all, we create the basic HTML structure:<div id="wrap"><div id="header"></div><div id="nav"></div><div id="main"></div><div id="sidebar"></div><div id="footer"></div></div>
<div id="wrap"><div id="header"><h1>Document Heading</h1></div><div id="nav"><ul><li><a href="#">Option 1</a></li><li><a href="#">Option 2</a></li>...</ul></div><div id="main"><h2>Column 1</h2><p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit...</p></div><div id="sidebar"><h2>Column 2</h2><p>Lorem ipsum dolor sit amet, consectetuer adipiscing elit...</p><ul><li><a href="#">Link 1</a></li><li><a href="#">Link 2</a></li>...</ul></div><div id="footer"><p>Footer</p></div></div>
2. Adjust the body and html elements
To make the content reach the edges of the browser window, we set the margin and padding of the body and html elements to zero. We also specify colours for text and background.body,html {margin:0;padding:0;color:#000;background:#a7a09a;}
3. On to the main containers
After that it’s time to give the content area a width and center it horizontally. We do that by specifying the width and margins of the main container,#wrap. We also give it a background colour to make it show up on the page.The method we use to center the content is based on the fact that when an element’s left and right margins are set to
auto,
they will share whatever is left when the element’s width has been
subtracted from that of its container. In this case the width of #wrap will be subtracted from the width of the browser window.Note: for this method to work in Internet Explorer (version 6 and later only), the document must use a DOCTYPE that forces IE to use its standards mode.
#wrap {width:750px;margin:0 auto;background:#99c;}
body
element to control the width and centering of the layout, it is because
doing so can cause unwanted side-effects in some versions of Internet
Explorer.After that, we give the different sections of the document different background colours to make them show up.
#header {background:#ddd;}#nav {background:#c99;}#main {background:#9c9;}#sidebar {background:#c9c;}#footer {background:#cc9;}
4. Place the columns side by side
To make the two columns (#main and #sidebar) display side by side we float them, one to the left and the other to the right. We also specify the widths of the columns.#main {float:left;width:500px;background:#9c9;}#sidebar {float:right;width:250px;background:#c9c;}
#wrap in Step 3.This will make
#sidebar appear to the right of #main, but the footer is not where it should be.5. Push the footer down
The footer doesn’t get pushed down to the bottom of the content because of the wayfloat works. When you float an element, it is removed from the document flow and doesn’t push elements that follow it down. In this case #footer will start right below #sidebar.To avoid this we use the
clear property to tell the footer that it can’t have any elements next to it.#footer {clear:both;background:#cc9;}
6. Fix the background colour
Now we can see that the shorter column doesn’t continue all the way down to the footer. To make it look like it does, we use the same background colour for#sidebar and #wrap.#sidebar {float:right;width:250px;background:#99c;}
If you don't know which column is going to be the tallest, and you
want both columns to have different backgrounds and look like they are
going all the way to the bottom, you need to use a workaround. There are
several ways to achieve that effect:
- Faux Columns
- Creating Liquid Layouts with Negative Margins
- In search of the One True Layout
7. Make the navigation bar horizontal
#nav contains a regular unordered list of links. Since we don’t want it to look like an unordered list we restyle it.#nav ul {margin:0;padding:0;list-style:none;}#nav li {display:inline;margin:0;padding:0;}
8. Adjust margins and paddings, and make IE 6 cooperate
Almost done. Time to adjust themargin and padding of some elements to make the layout a little less cramped.#header {padding:5px 10px;background:#ddd;}h1 {margin:0;}#nav {padding:5px 10px;background:#c99;}#main {float:left;width:480px;padding:10px;background:#9c9;}h2 {margin:0 0 1em;}#sidebar {float:right;width:230px;padding:10px;background:#99c;}#footer {clear:both;padding:5px 10px;background:#cc9;}#footer p {margin:0;}
#main and #sidebar, we subtracted the width of the left and right paddings from each element’s width. This is how the CSS box model works – for more details on that, see Internet Explorer and the CSS box model.And the final thing is to compensate for a float bug in Internet Explorer 6. If you look at step 6 in IE 6, you’ll notice that the footer is not always being pushed completely below
#main. Scroll up and down a couple of times if you can’t see it immediately.It is very noticeable in this demo because every major element has a different background colour and everything is really tight. One way of fixing this problem is making sure the footer has an Internet Explorer concept called Layout. There are several ways of achieving this, but we’ll do it by using the Star HTML CSS hack to give the footer a height only in IE 6:
* html #footer {height:1px;}
And we’re done. We have created a simple layout that can be used as a starter for more advanced layouts.
View the final layout.
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