Quick CSS Mockups with Photoshop

You need to make a set of web design mockups for your client. You’d like to find an easy way to show these mockups in clean XHTML and CSS code, because plain JPGs don’t convey the full sense of the design, and sliced tables are evil. In fact, let’s forget table slices ever existed.
Caveat: This article is for people who need to produce valid, standards-compliant mockups quickly, with the graphics tools they already use. This is not a production technique for people who want to get the most benefit out of (X)HTML by creating structural, semantic markup. Creating structural, semantic markup, as A List Apart and most standardistas recommend, still takes time, thought, and hand-coding.
WYSIWYG graphics editors such as Fireworks, GoLive, and ImageReady allow you to generate HTML code, but the exported code tends to use tables or absolute positioning. That’s so 1999. So what, then, can these programs do in terms of producing valid and useful code? More than you think. I’ll show you an easy way to produce mockups with Photoshop, prepare them for the web with ImageReady, and clean up the code afterward.

Background

I must admit, Fireworks was a major part of my design arsenal until I started taking accessibility and standards compliance seriously, and I don’t think I’m alone here. The problem I ran into was that I could only export HTML code using tables, when what I really wanted was relatively positioned div elements. Only with ridiculous hours of coding and copious quantities of caffeine could you convert such a table to relative divs, and this just steals more time from when you could have been designing more mockups or sleeping. So why start off with a sliced table at all? What I needed was a way to generate clean relatively positioned divs—or, barring that, code that was close enough that it wouldn’t take aeons to make it play nice with W3C standards. These days, this is surprisingly straightforward with ImageReady.

Make ImageReady CSS-ready

Adobe Photoshop CS ships with a web-focused sidekick: ImageReady CS. Adobe Fireworks is great for vector applications, but less so for raster work. Conversely, ImageReady is perfectly suited for raster work, but less so for vector work (although that’s changing). Using ImageReady, you can export slices as absolutely positioned divs, which can be easily transformed into relatively positioned divs.
This means you can start off in Photoshop to do all your complex masking, fades, Illustrator vector art, filters, etc., and then switch to ImageReady to slice up your layout. You’ll want to be sure that your layout is aligned to the top left; don’t try to center it just yet—that’s a job for CSS later on. Using ImageReady, you can style your navigation menu items (unless you’re doing that with pure text / CSS) and set rollover states. (For a production layout, you would probably shy away from Adobe rollovers and actions in favor of your own JavaScript or CSS rollovers, but for mockup use, these rollover states should suffice.)

Slice it up

Use the Slice tool to create your slices. Once you’re finished use the Slice Select tool to select and rename each section. For example, you may have a header that will become a div tag later on. ImageReady would really like to call this “Yourfile_1_01,” but you’ll save yourself some work by giving it a logical name from the start, like “header”. You will use this later on when editing your CSS. The same goes for the content area, any side columns, the footer, and other areas you may want to define.
Jump back and forth between designing in Photoshop and ImageReady until you’re ready to test out your design in a browser. Then, in ImageReady, go to File › Preview In › (insert favorite browser here). See whether your slices look and behave as intended, and modify your optimization settings accordingly. Exported slices will result in JPG or GIF images inserted into div tags with img tags; later, you may want to insert some of the images as background images for the individual divs instead.

Exporting HTML & CSS

Set your output settings: select File › Output Settings › HTML and change the settings to your liking. Note that you can opt to generate XHTML code. Select “Next” and check the settings in Saving HTML Files.
Select “Next” again; this brings you to Slices. Here you can choose to “Generate CSS.” Next to Referenced, you’ll see a dropdown menu that allows you to choose By ID, Inline, or By Class. Select By ID. You can also get detailed with slice naming conventions if you’re so inclined.
Export your mockup to (X)HTML/CSS using File › Save Optimized As, and choose a location that makes sense to you. Note that ImageReady will create an /images subdirectory in the same location where you save the HTML file. (Line wraps marked » —Ed.)

Toast, anyone?We now have slices consisting of absolutely positioned divs, with the CSS contained directly in the HTML file’s head. Maybe absolutely positioned divs are just what you need—if so, grab a cup of coffee and relax. Otherwise, let’s take things a step further by converting these divs to relative positioning.
First, make a copy of the ImageReady-generated HTML file and open it in your code editor (e.g. Dreamweaver, BBEdit, or another favorite editor). You’ll probably want to wrap all your divs inside an outside container div to control your mockup layout more precisely. ImageReady exports the CSS slices as divs and wraps them in a container div called “Table_01.” Rename the “Table_01” div (to “container”, for example) and style it with CSS as you see fit. If you don’t need a container div, just delete the “Table_01” div and its CSS counterpart.
Next, switch all your other divs to relative positioning by removing the absolute positioning declarations and letting them inherit relative positioning. Pay special attention to your floats and clears. You could try to switch all your divs at once, but a more precise and predictable way to go about it is to change one div at a time and check each div individually.
For divs that contain images, decide which should be turned into CSS background images and which really deserve an image tag. Some slices (a content area, for example) may be of a single color and thus should be set using a CSS style without any images. Set the overall page background separately using your stylesheet. If this were a production layout, you’d probably move your CSS to an external stylesheet, but that may be overkill for single-page mockups. Validate your code and you’re good to go.
You’ll need to add appropriate height and width declarations back in if the image in this element becomes a background image in a later revision.

CSS Layout Techniques: for Fun and Profit

Look Ma, No Tables.
If you are looking for help making the transition to CSS layout (that's Cascading Style Sheets), you've come to the right place. I am cataloging here as many useful cross-browser CSS layout techniques as I can find, and some that I made up when I was bored last Thursday. All the examples on this site have been reduced to only their essential code, and you will find the source displayed on each page to hopefully make it quick and easy to understand the inner workings of the CSS. Feel free to steal all the code you find on this site, and consider linking back here on your site or in your source comments.
You will also find below links to various online CSS resources and tutorials, appropriate for both the novice and the seasoned CSS veteran.
I started this collection because of the dearth of resources I found out there when I went looking for information on how to translate typical table based layouts to CSS layouts. I know it is not nearly exhaustive, so if you see that there is something missing, whether it is a particularly good tutorial, or a site that is using a complex CSS layout, please let me know about it. I will pay you $3750 for each link you submit that I use.
If you don't have any idea why anyone cares about this topic, because like tables can do all that stuff and more, please read this: To Hell with Bad Browsers. And then read this follow up interview with Zeldman. And then read about the Web Standards Project's Browser Upgrade campaign. The future is bright, kids!

CSS Techniques
CSS layout techniques and the sites that use them.
3 Columns, The Holy Grail of page layouts — The most elegant technique and perhaps the most sought after layout: a 3 column page with a fluid center column. Easy to understand, easy to implement. I first saw this layout at dynamic ribbon device and have since learned that the sweet CSS came from Rob Chandanais of BlueRobot. Owen also made a very nice tutorial using this layout technique.
2 Columns, ALA Style — Famously chronicled by Jeffrey Zeldman in his ALA article A Web Designer's Journey, this is an extremely easy layout to implement requiring only a simple float:left declaration.
4 Columns, All Fluid — This technique can actually be used to provide as many columns on a page as you like. Drawback #1) it gets difficult quickly if you want to make any of the columns a fixed width. Drawback #2) it relies heavily on percentages, which the various browsers all calculate differently, so you can't place your columns very precisely. Still, a very useful technique, especially if you don't want borders and different background colors for your columns.
3 Columns, All Fluid — A much simpler and potentially more useful technique that then 4 column technique above. It uses float:left, suffers from needing percentage widths for each column, and from potential column wrapping when the browser window is narrowed.
Static Width and Centered — 3 columns all with static widths, and contained in a parent DIV which remains centered in the window. One rather serious limitation of this particular technique is that if any of the three content DIVs contains an image or a really long word that is longer than the width of the DIV, it totally breaks the layout. Each browser breaks it differently.
Nested Float — A very simple layout that features a nested, floated menu in the upper right. Easily reversed. A variation of this technique is in use on this very page.Dealing with the CSS box Model — IE5 Mac, NS6, Opera 5; they all handle borders and padding correctly, adding them to the width of the box. But IE5 PC gets it all wrong, placing them within the width of the box. IE5 PC's implementation is arguably easier to work with (scratch that, it is easier to work with), but that is beside the point. How do you deal with this discrepancy between the browsers? There are ways, my friends, there are ways.-->
straight to the top
CSS Resources
Specs, primers, validators, stuff like that
The CSShark Answers FAQs — Martina Kosloff has compiled a pretty good FAQ on CSS. Worth your time.
css/edge — From the mind of Eric Meyer comes this great little site pushing CSS to the edge. It is, in his words: "intended, first and foremost, to be as relentlessly creative with CSS as we have been practical all these years. It does not exist to present or explain safe cross-browser techniques; in fact, almost the opposite. The goal here is to find ways to make CSS live up to its fullest potential, with only minimal regard to browser limitations."
websitetips.com CSS section — Literally a ton of links to CSS resources from all over. A better set of links than this one by far.
Guide to Cascading Style Sheets from the Web Design Group. — An excellent primer if you need to start from scratch. It features a tutorial, a reference section, a syntax validator, and more CSS links. A little dated, but still an excellent place to start.