Most Web page designers use a table-based layout to achieve a coherent and consistent look. There's a different way to achieve the same look. Using CSS and DIV tags reduces markup code, speeds up page downloads, separates content from its visual presentation, and brings your code closer to Web standards compliance--all while making your website more appealing to search engine spiders. Alejandro Gervasio explains how it's done, with copious examples.
The corresponding visual representation is shown below:
Let’s explain in detail the code for this layout. As in the previous example, we make our “leftcol” DIV float to left and its width is set to 20%. Our “content” DIV is floated to left and its width is set to 59%, while our recently added “rightcol” DIV is floated to the right, and its width is set to 20% too. Header and Footer DIVS are kept to the same width of 100%.
Finally, we have reached our main goal, having a Web page layout that expands nicely, filling the whole screen space flawlessly. The “elastic” concept is well deserved here.
One final consideration is worth noting: since DIVS containers will expand down as we insert more elements into them, sooner or later, we will end up with different heights for each column of the Web page. How can we make them have the same heights? With a little bit of JavaScript, we can achieve the desired result. That will be considered as homework, since it’s out of the scope of this article.
Wrapping Up
As seen on the examples presented here, DIV layout with CSS is a very powerful technique, well-suited to face different design approaches and styles, and a big improvement for our background as Web designers. Web pages are faster to download, avoid useless markup, look more appealing to search engines, and keep us closer to Web standards. There is a lot to gain in migrating from table-based to div-based layout. Just give it a try. Good luck!
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