2 posts on User Interfaces In CSS

CSS Counters have a lot more potential than most web developers seem to think. The common use case consists of something like:

somecontainer { counter-reset: foocount; }
Ε { counter-increment: foocount; }
Ε::before { content: counter(foocount) ". "; }

commonly used to add numbering to section headings or re-create an

's counters in order to style them (since browser support for ::marker is ridiculous).

Have you ever thought of applying the counter to different elements than the ones being counted? This way we’re able to count elements and display their total count somewhere with CSS alone! (and with the variety of selectors in CSS3, I see great potential here…). I’m referring to something like:

ul { counter-reset:foo; }
li { counter-increment:foo; }
p::after { content:counter(foo); }

From my tests, this works flawlessly in Firefox, Safari, Opera and Chrome (I’ve only checked the latest stable though), as long as the element that displays the count comes after the elements being counted (in the markup).

Another underutilized aspect of CSS counters (well, far less underused than the above, but still) is how we can combine multiple in the same pseudoelement. For instance, to count rows and cells of a table and display the count inside each cell:

table {
	counter-reset:row;
}
tr {
counter-increment:row;
counter-reset:cell;
}
td {
counter-increment:cell;
}
td::after {
content:counter(row, upper-alpha) counter(cell);
}

Which displays counters like A1, A2, A3, B1, B2, B3, etc in the cells. When the content property is more properly implemented, you wouldn’t even need the last rule.

Last but not least, a CSS3 Reversi UI (no images used!) I created a while ago that demonstrates the above (and various other things, like --finally-- a use case for :empty :P ). Looks fine only in Firefox and Opera 10.5, due to lack of support for inset box shadows in Safari and buggy support in Chrome. Works fine in all 4 of them (IE is out of the question anyway).



The displayed counts of each player’s pieces (top right corner) are just CSS counters. Same goes for every cell’s name. This is mostly a proof of concept, since it’s impossible to determine if someone won by CSS alone, so we would have to count the pieces in JS too.

As a game it’s not finalized, you are basically only able to play against yourself and it doesn’t know when somebody won, so it’s not very useful or enjoyable. If someone wants to take it up and develop it further be my guest.

Note to avoid confusion: CSS Counters are not CSS 3. They are perfectly valid CSS 2.1. The “CSS3” in the title (“CSS3 Reversi”) is due to other techniques used in it’s UI.

Yeap, this is yet another of those things that make no practical sense but are fun to make just to see whether it can actually be done. It’s also a proof of the fact that when I have too many things to do, I tend to procrastinate more. :P

Here it is (resize the window to get the narrow version ;)):

http://lea.verou.me/demos/iphone-keyboard/

It should look correct in Firefox 3.6, Chrome 4 and Safari 4. It looks best on Firefox 3.6 due to it’s ability to render subpixel distances, whereas other browsers just round everything to the closest pixel. It also looks best in computers with Helvetica installed (it’s installed by default on macs btw) but it should look sufficiently OK with Arial too, since it’s a rip-off of Helvetica ;) (the only problem with Arial is that the line-height of the buttons with the symbols will be slightly different since the custom font’s measurements are based on Helvetica Bold) Also, ironically, it doesn’t look ok in the iPhone!

For those of you that don’t use one of the aforementioned browsers as your primary and are way too bored to switch (or don’t even have them installed (!)), here are two screenshots from Firefox 3.6 (nicely cropped to only contain the keyboard):

As for how it’s done, as you can easily see, most of it is run-of-the-mill for someone with a decent grasp on CSS3: media queries, CSS gradients, shadows, border-radiuses and RGBA. The only tricky part is the symbols for shift, backspace and international. I have to admit I cheated a bit here: I didn’t use images, but I used @font-face with a custom font that just contains these 3 symbols. The reasons behind that are that this way I wouldn’t have to create 2 versions of the symbols (light and dark, for pressed and normal states respectively) and that they are vector, so they scale (try zooming in).

Please note that there’s no functionality attached to it. It’s just an interface. I wasn’t interested at making an on-screen keyboard in general, I was just interested to see if a keyboard visually identical to iPhone’s is possible with CSS alone. If someone wants to actually use it and/or develop it further, you’re free to do so, as long as you keep the comment at the start of the css file. ;)

An interesting discussion about this could be “What would be the ideal markup to semantically style a keyboard?”. Personally, I just paid attention to the more pragmatic objectives of making the keys focusable, and keeping the complexity of the DOM tree to a minimum, so you might find it semantically wrong (I used a <ul> for the container, <li>s for the rows and <button>s for the keys) – but what is right actually in this case? Is a keyboard a list or a table of keys? I don’t think so…