Yes. Which means you mostly have to already have the basic idea of which content goes where and much navigational structure already, otherwise you have nothing to start with (and this is sketches on paper and whatnot, though I know there are some very expensive wireframing programs out there as well).
So you have an idea of the ideal source order, and you start throwing examples of it into HTML (even if it's just divs, but ideally you have enough real content to use appropriate tags), and then with CSS you just do real quick outlines: use borders or background colours to show sizes and positions, and really nothing more.
The benefits of this are: this basic setup will already work cross-browser, because you built it that way. It also gives you examples you can show on screens of various sizes, so assuming the content is not supposed to be radically different for mobile, you can show right there and then what these boxes will do on "mobile" size screens. Or TVs. Or whatever.
Throw it up on a server and the client can see it as well. If you choose garish colours then nobody will wonder if that's the real colourscheme (we've all heard web companies say sometimes their clients think the lorem ipsum is the real text and "we don't speak Latin here"!). Colourschemes and fonts and spacing and whatnot come later.
I would think that this would be when you bring in the designer. They have a skeleton they can see and play with on a screen, and then they can do whatever mockups they want to show the clients. If they either know CSS themselves or work with the front-ender, that's ideal. The Designer can come up with ideas and the front-ender can implement them, and at some point the basic layout is stable enough that the designer can go make a "mockup" for the client to look at. There, the client is approving fonts, colours, spacing, shadows, whatever. All that extra stuff.
And after the the client okays that and the front-ender has a go at implementing it, time for more user testing! Those colours sure are perdy, but are they readable?
One of the biggest mistakes charity web sites make is not making it clear how to donate! for example. Some of those sites look great! They were done by professional designers. But the content didn't come first (and that may not have been the designers' fault, but whoever thought up the content-flow of the site, or the lack of usability testing).
To me, the idea that you draw for clients a picture of how their website might look in Safari 5 on a 27" Cinemac monitor, and then several more, and then have the client pick one... sounds like an idea fit for vanity sites like luxury products (who even today are mostly Flash). Those aren 't really web sites, they're large web-based advertisements, works of art on their own. They aren't supposed to do much except look pretty. They aren't supposed to work on a wide scale of screen sizes.
But I also realise that's how much of the business works. Client
expect to see several, full-scale and almost-complete-looking mockups, because yes, they don't know what they want til they see it. That's pretty much endemic in humans. Also, when several companies are bidding for a project, the winner is often based on who makes the prettiest mockup. But if you're starting with the design they pick and then trying to stuff the necessary content inside, I personally believe that makes usability problems where none should have started. It means that drawing of a website on a 27" monitor now needs a whole new idea for the "mobile" version.
View
this page* in a small (less than 400px wide) browser. That's actually what I started with (minus the colours and stuff). I wrote that design first, in CSS (layout-wise). Later I took that HTML and made a "CSS mockup" of what it would be the main page on desktop, so the boss could see and okay it (or not). He wanted changes with the buttons and whatnot, it was shuffled around a bit, but he never saw the mobile base (maybe by now he has). Since the mobile base was *mostly* done, it was pretty easy to hang stuff on it for the "desktop" version, and you see in the mobile style just background colours... I made the actual images like the logo and the textured stuff later.
*the markup is only partially mine. Every time I show that site, I also cringe and want to point to my actual code and say "see??" but, meh. I need to learn to deal with dirty paws on my code and grow up.
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