CSS3 and HTML5: Does Now Really Mean Now

CSS3 and HTML5

Does now really
mean now?
Saturday, 10 March 2012

Hi! I’m Chris Mills
‣ Open standards advocate and education agitator
‣ dev.opera.com editor
‣ W3C web education community group chair
‣ Accessibility whiner
‣ HTML5/CSS3 wrangler
‣ Heavy metal drummer & proud dad


cmills@opera.com
@chrisdavidmills
http://www.slideshare.net/chrisdavidmills
http://dev.opera.com
http://www.w3.org/community/webed/


What we’ll talk about
‣ Do you really need The Shiny™?
‣ Progressively enhance, don’t rely on it
‣ When progressive enhancement isn’t viable,
provide alternatives, use feature detection...
‣ ...use polyfills/shims
‣ #sxsw #dnrmn (lol, lmao, wtf, etc.)


Do you need it at all?


HTML5 and CSS3 are fun
‣ But just because you can use them doesn’t mean
you have to use them. All the bloody time!
‣ In the real world, with real clients, you are likely to
have less freedom


Do you need it?


If you are going to use
prefixed CSS/JS...
background: -webkit-linear-gradient(#ff0000,
#000000);
background: -moz-linear-gradient(#ff0000,
#000000);
background: -ms-linear-gradient(#ff0000,
#000000);
background: -o-linear-gradient(#ff0000,
#000000);
background: linear-gradient(#ff0000, #000000);


Progressive
enhancement


Don’t rely on The Shiny™
‣ If *at all possible*
‣ Build a base level of functionality that works
‣ Then enhance the user experience


Example: Ajax
‣ Ajax makes data updates more responsive
‣ But the base functionality could still work with no
Ajax
‣ Albeit with page reloads


Example: Offline apps
‣ Using apps offline is awesome
‣ But you’re probably not losing anything if your
browser doesn’t support this
‣ http://dev.opera.com/articles/view/taking-your-
web-apps-offline-web-storage-appcache-
websql/


Example: CSS3 bling
‣ Content looks a lot nicer in supporting browsers
‣ Also more flexible than using old graphical
methods
‣ But the content should still be accessible in older
browsers
‣ http://www.alistapart.com/articles/css3-bling-in-
the-real-world/


Example: CSS animation
‣ If done properly, a lot of CSS animations and
transitions can be used unobtrusively
‣ For example, by default the element is set to be
in its usable state, but then the animation is
applied over the top to bring the animation to that
state


Example: Media queries
‣ One of the obvious ones!
‣ If media queries are not supported, the browser
ignores them, and you get the standard layout
‣ Of course, this can be a problem if you are using
the “mobile first” approach


Example: Web fonts
‣ This is a perfect feature to use now!
‣ IE has supported EOT since IE4/5!
‣ You can use the bulletproof web font syntax - see
fontsquirrel.com


This is all fine...
‣ So long as your boss/client is cool with that!
‣ Many still obsess over identical layouts/
functionality across browsers


Identical layout/functionality
obsession
‣ A thing of the past?
‣ It is becoming much less of an issue, with so
many different browsing platforms and devices
now available
‣ Many different contexts require different layouts/
functionality for a good user experience


Acceptable
alternatives

Ok, sometimes progressive
enhancement isn’t really possible
‣ <img>!
‣ <canvas>/WebGL
‣ <video>
‣ Web sockets
‣ etc.


Fallbacks often a good option
‣ Equivalence of service
‣ Useful for multiple user groups
‣ As long as they can access the content and
services in some way, you should be ok


HTML5 <video>
‣ Typical example of HTML5’s attitude to fallback


HTML5 <video>
<video controls>
<source src="video-file.mp4"
type="video/mp4">
<source src="video-file.webm"
type="video/webm">
<track src="en.vtt" kind="subtitles"
srclang="en" label="English subtitles">

</video>

Flash fallbacks viable
‣ Might seem annoying to have to implement, but
once you’ve got a template, you’re off.
‣ And Flash can just load the MP4 version of the
video
‣ Also consider jPlayer, Sublime, etc.


Unfortunately...
‣ The fallback content is for browsers that don’t
support <video>
‣ Not for browsers that don’t support the format
being offered up
‣ You’ll need multiple formats for the time being


What about when alternative
mechanisms don’t exist?
‣ Make your own!
‣ Use feature detection
‣ Basic tests, or a library like Modernizr


Feature detection basics
if (window.chrome) {
// do stuff that works on Chrome
}
else {
// ignore it, and do something else
}


Feature detection basics
if (checkVideo()===true) {
// do stuff that uses this method
}
else {
// ignore it, and do something else
}


Modernizr
‣ The mother of all feature detection libraries
‣ Available at modernizr.com


Modernizr CSS example
<html lang="en-US" class="no-js">
<head>
...
<script src="modernizr.js"></script>
...
</head>


#wrapper:hover, #wrapper:focus {
transform: rotateX(180deg);
}


.no-csstransforms3d #wrapper #front {
transition: 0.8s all ease-in;
}

.no-csstransforms3d #wrapper:hover #front,
.no-csstransforms3d #wrapper:focus #front {
transform: rotate(-30deg) translate(-50%,-100%);
}


Modernizr JS example
function rotateForm() {
if(Modernizr.cssanimations) {
form.setAttribute("class","form-rotate");
form.style.left = "0rem";
} else {
back.style.zIndex = "5";
};
};


In general, Modernizr rocks
‣ It can add a fair bit of weight to your page: 49KB
for the full library
‣ But you can create a smaller custom version that
just includes the tests you need
‣ There are some things that can’t be detected


IE conditional comments

Polyfills/shims


Add in support where needed
‣ Using JavaScript
‣ Fake SVG in old IE versions using VML
‣ Fake box-shadow using IE filters (although they
are evil — every time you use IE filters, god kills a
kitten)


Adding HTML5 support to
browsers
‣ Older browsers don’t support them!
‣ But you can style any unknown element, so just
set all the “block level” elements to display as
block, at the top of your CSS:
‣ article { display: block; }


Oh, but IE 6-8 need
some more help
‣ They refuse to style unknown elements, unless
you create instances of them in the DOM
‣ document.createElement('article');


CSS3 PIE for CSS bling support
‣ http://css3pie.com/
‣ Awesome little library
‣ Add support to IE6-8 for box-shadow, border-
radius, gradients and transparent colours
‣ But not text-shadow, which is a little frustrating


CSS3-mediaqueries.js
‣ http://code.google.com/p/css3-mediaqueries-js/
‣ Add media queries support to IE
‣ A bit clunky, when you resize, but it works


Excanvas
‣ http://excanvas.sourceforge.net/
‣ Add <canvas> support to IE


Selectivizr
‣ http://selectivizr.com/
‣ Adds support for CSS3 selectors to IE6-8


All sounds good, huh?
‣ Beware: slows down loading!
‣ Especially stuff that makes use of IE filters
‣ Can be mitigated by helpers such as YepNope


To summarise


Does now really mean now?


Progressive enhancement and
alternatives
‣ Can be successful
‣ But not everything is easy to provide for
‣ And your clients might not approve


Polyfills
‣ Are great
‣ But complicate things
‣ And give a performance hit


Think carefully
‣ Do you need to do it this way?
‣ Is there viable alternative content that can be
provided, or different ways to implement it?


It will be a while before
things get easier


More resources
‣ html5please.com
‣ caniuse.com
‣ Practical CSS3: design and develop (Peachpit
Press, August 2012ish)


Thanks!
cmills@opera.com
@chrisdavidmills
http://www.slideshare.net/chrisdavidmills
http://dev.opera.com
http://www.w3.org/community/webed/


Thank you CC!
Spidermen — http://www.flickr.com/photos/ralphman/792848885/
Schoolkids — http://www.flickr.com/photos/mallalamuseum/3838470381/
Old married couple — http://www.flickr.com/photos/adwriter/257937032/
No IE6 — http://www.navegabem.com
Parrot — http://www.flickr.com/photos/young-in-panama/57895100/
Immortal — 10 most ridiculous black metal photos ever


CSS3 and HTML5: Does Now Really Mean Now

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