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| author | Bartek Szopka <bartek.szopka+github@gmail.com> | 2012-03-28 22:03:28 +0000 |
|---|---|---|
| committer | Bartek Szopka <bartek.szopka+github@gmail.com> | 2012-04-07 07:39:19 +0000 |
| commit | 24cef7f5057c4d2dedbd5f60640c64da09181d02 (patch) | |
| tree | face1b6d13837c74277a522d64b8d06e29da678e | |
| parent | edff5a08c1903960e0550377a07bde9684774654 (diff) | |
| download | impress.js-24cef7f5057c4d2dedbd5f60640c64da09181d02.tar.gz | |
some CSS tricks described in comments
| -rw-r--r-- | css/impress-demo.css | 523 |
1 files changed, 365 insertions, 158 deletions
diff --git a/css/impress-demo.css b/css/impress-demo.css index 1f137cf..75fd1ad 100644 --- a/css/impress-demo.css +++ b/css/impress-demo.css @@ -1,15 +1,31 @@ -/** - * This is a stylesheet for a demo presentation for impress.js - * - * It is not meant to be a part of impress.js and is not required by impress.js. - * I expect that anyone creating a presentation for impress.js would create their own - * set of styles. - */ - - -/* http://meyerweb.com/eric/tools/css/reset/ - v2.0 | 20110126 - License: none (public domain) +/* + So you like the style of impress.js demo? + Or maybe you are just curious how it was done? + + You couldn't find a better place to find out! + + Welcome to the stylesheet impress.js demo presentation. + + Please remember that it is not meant to be a part of impress.js and is + not required by impress.js. + I expect that anyone creating a presentation for impress.js would create + their own set of styles. + + But feel free to read through it and learn how to get the most of what + impress.js provides. + + And let me be your guide. + + Shall we begin? +*/ + + +/* + We start with a good ol' reset. + That's the one by Eric Meyer http://meyerweb.com/eric/tools/css/reset/ + + You can probably argue if it is needed here, or not, but for sure it + doesn't do any harm and gives us a fresh start. */ html, body, div, span, applet, object, iframe, @@ -58,25 +74,35 @@ table { border-spacing: 0; } - +/* + Now here is when interesting things start to appear. + + We set up <body> styles with default font and nice gradient in the background. + And yes, there is a lot of repetition there because of -prefixes but we don't + want to leave anybody behind. +*/ body { font-family: 'PT Sans', sans-serif; - min-height: 740px; - + background: rgb(215, 215, 215); background: -webkit-gradient(radial, 50% 50%, 0, 50% 50%, 500, from(rgb(240, 240, 240)), to(rgb(190, 190, 190))); background: -webkit-radial-gradient(rgb(240, 240, 240), rgb(190, 190, 190)); background: -moz-radial-gradient(rgb(240, 240, 240), rgb(190, 190, 190)); + background: -ms-radial-gradient(rgb(240, 240, 240), rgb(190, 190, 190)); background: -o-radial-gradient(rgb(240, 240, 240), rgb(190, 190, 190)); - background: radial-gradient(rgb(240, 240, 240), rgb(190, 190, 190)); - - -webkit-font-smoothing: antialiased; + background: radial-gradient(rgb(240, 240, 240), rgb(190, 190, 190)); } +/* + Now let's bring some text styles back ... +*/ b, strong { font-weight: bold } -i, em { font-style: italic} +i, em { font-style: italic } +/* + ... and give links a nice look. +*/ a { color: inherit; text-decoration: none; @@ -92,20 +118,56 @@ a { transition: 0.5s; } -a:hover { +a:hover, +a:focus { background: rgba(255,255,255,1); text-shadow: -1px -1px 2px rgba(100,100,100,0.5); } -/* enable clicking on elements 'hiding' behind body in 3D */ -body { pointer-events: none; } -#impress { pointer-events: auto; } +/* + Because the main point behind the impress.js demo is to demo impress.js + we display a fallback message for users with browsers that don't support + all the features required by it. + + All of the content will be still fully accessible for them, but I want + them to know that they are missing something - that's what the demo is + about, isn't it? + + And then we hide the message, when support is detected in the browser. +*/ -/* COMMON STEP STYLES */ +.fallback-message { + font-family: sans-serif; + line-height: 1.3; + + width: 780px; + padding: 10px 10px 0; + margin: 20px auto; + + border: 1px solid #E4C652; + border-radius: 10px; + background: #EEDC94; +} + +.fallback-message p { + margin-bottom: 10px; +} + +.impress-supported .fallback-message { + display: none; +} + +/* + Now let's style the presentation steps. + + We start with basics to make sure it displays correctly in everywhere ... +*/ .step { + position: relative; width: 900px; padding: 40px; + margin: 20px auto; -webkit-box-sizing: border-box; -moz-box-sizing: border-box; @@ -114,12 +176,19 @@ body { pointer-events: none; } box-sizing: border-box; font-family: 'PT Serif', georgia, serif; - font-size: 48px; line-height: 1.5; } -.step { +/* + ... and we enhance the styles for impress.js. + + Basically we remove the margin and make inactive steps a little bit transparent. +*/ +.impress-enabled .step { + margin: 0; + opacity: 0.3; + -webkit-transition: opacity 1s; -moz-transition: opacity 1s; -ms-transition: opacity 1s; @@ -127,62 +196,59 @@ body { pointer-events: none; } transition: opacity 1s; } -/* fade out inactive slides */ -.step:not(.active) { - opacity: 0.3; -} - -/* STEP SPECIFIC STYLES */ - -/* hint on the first slide */ +.impress-enabled .step.active { opacity: 1 } -.hint { - position: fixed; - left: 0; - right: 0; - bottom: 200px; +/* + These 'slide' step styles were heavily inspired by HTML5 Slides: + http://html5slides.googlecode.com/svn/trunk/styles.css - background: rgba(0,0,0,0.5); - color: #EEE; - text-align: center; + ;) + They cover everything what you see on first three steps of the demo. +*/ +.slide { + display: block; + + width: 900px; + height: 700px; + padding: 40px 60px; + + background-color: white; + border: 1px solid rgba(0, 0, 0, .3); + border-radius: 10px; + box-shadow: 0 2px 6px rgba(0, 0, 0, .1); + + color: rgb(102, 102, 102); + text-shadow: 0 2px 2px rgba(0, 0, 0, .1); + + font-family: 'Open Sans', Arial, sans-serif; + font-size: 30px; + line-height: 36px; + letter-spacing: -1px; +} + +.slide q { + display: block; font-size: 50px; - padding: 20px; - - z-index: 100; - - opacity: 0; - - -webkit-transform: translateY(400px); - -moz-transform: translateY(400px); - -ms-transform: translateY(400px); - -o-transform: translateY(400px); - transform: translateY(400px); + line-height: 72px; - -webkit-transition: opacity 1s, -webkit-transform 0.5s 1s; - -moz-transition: opacity 1s, -moz-transform 0.5s 1s; - -ms-transition: opacity 1s, -ms-transform 0.5s 1s; - -o-transition: opacity 1s, -o-transform 0.5s 1s; - transition: opacity 1s, transform 0.5s 1s; + margin-top: 100px; } -.impress-on-bored .hint { - opacity: 1; - - -webkit-transition: opacity 1s 5s, -webkit-transform 0.5s; - -moz-transition: opacity 1s 5s, -moz-transform 0.5s; - -ms-transition: opacity 1s 5s, -ms-transform 0.5s; - -o-transition: opacity 1s 5s, -o-transform 0.5s; - transition: opacity 1s 5s, transform 0.5s; - - -webkit-transform: translateY(0px); - -moz-transform: translateY(0px); - -ms-transform: translateY(0px); - -o-transform: translateY(0px); - transform: translateY(0px); +.slide q strong { + white-space: nowrap; } -/* impress.js title */ +/* + And now we start to style each step separately. + + I agree that this may be not the most efficient, object-oriented and + scalable way of styling, but most of steps have quite a custom look + and typography tricks here and there, so they had to be styles separately. + + First is the title step with a big <h1> (no room for padding) and some + 3D positioning along Z axis. +*/ #title { padding: 0; @@ -215,8 +281,12 @@ body { pointer-events: none; } font-size: 32px; } -/* big thoughts */ - +/* + Second step is nothing special, just a text with a link, so it doesn't need + any special styling. + + Let's move to 'big thoughts' with centered text and custom font sizes. +*/ #big { width: 600px; text-align: center; @@ -235,17 +305,23 @@ body { pointer-events: none; } line-height: 150px; } -/* tiny ideas */ - +/* + 'Tiny ideas' just need some tiny styling. +*/ #tiny { width: 500px; text-align: center; } -#ing { - width: 500px; -} +/* + This step has some animated text ... +*/ +#ing { width: 500px } +/* + ... so we define display to `inline-block` to enable transforms and + transition duration to 0.5s ... +*/ #ing b { display: inline-block; -webkit-transition: 0.5s; @@ -255,6 +331,10 @@ body { pointer-events: none; } transition: 0.5s; } +/* + ... and we want 'positioning` word to move up a bit when the step gets + `present` class ... +*/ #ing.present .positioning { -webkit-transform: translateY(-10px); -moz-transform: translateY(-10px); @@ -263,6 +343,9 @@ body { pointer-events: none; } transform: translateY(-10px); } +/* + ... 'rotating' to rotate quater of a second later ... +*/ #ing.present .rotating { -webkit-transform: rotate(-10deg); -moz-transform: rotate(-10deg); @@ -277,6 +360,9 @@ body { pointer-events: none; } transition-delay: 0.25s; } +/* + ... and 'scaling' to scale down after another quater of a second. +*/ #ing.present .scaling { -webkit-transform: scale(0.7); -moz-transform: scale(0.7); @@ -291,7 +377,9 @@ body { pointer-events: none; } transition-delay: 0.5s; } -/* imagination */ +/* + The 'imagination' step is again some boring font-sizing. +*/ #imagination { width: 600px; @@ -301,8 +389,16 @@ body { pointer-events: none; } font-size: 78px; } -/* use the source, Luke */ - +/* + There is nothing really special about 'use the source, Luke' step, too, + except maybe of the Yoda background. + + As you can see below I've 'hard-coded' it in data URL. + That's not the best way to serve images, but because that's just this one + I decided it will be OK to have it this way. + + Just make sure you don't blindly copy this approach. +*/ #source { width: 700px; padding-bottom: 300px; @@ -317,8 +413,14 @@ body { pointer-events: none; } font-size: 60px; } -/* it's in 3D */ - +/* + And the "it's in 3D" step again brings some 3D typography - just for fun. + + Because we want to position <span> elements in 3D we set transform-style to + `preserve-3d` on the paragraph. + It is not needed by webkit browsers, but it is in Firefox. It's hard to say + which behaviour is correct as 3D transforms spec is not very clear about it. +*/ #its-in-3d p { -webkit-transform-style: preserve-3d; -moz-transform-style: preserve-3d; /* Y U need this Firefox?! */ @@ -327,6 +429,12 @@ body { pointer-events: none; } transform-style: preserve-3d; } +/* + Below we position each word separately along Z axis and we want it to transition + to default position in 0.5s when the step gets `present` class. + + Quite a simple idea, but lot's of styles and prefixes. +*/ #its-in-3d span, #its-in-3d b { display: inline-block; @@ -402,95 +510,194 @@ body { pointer-events: none; } transform: translateZ(0px); } -/* overview step */ - -#overview { - z-index: -1; - padding: 0; -} +/* + The last step is an overview. + There is no content in it, so we make sure it's not visible because we want + to be able to click on other steps. -/* on overview step everything is visible */ +*/ +#overview { display: none } +/* + We also make other steps visible and give them a pointer cursor using the + `impress-on-` class. +*/ .impress-on-overview .step { opacity: 1; cursor: pointer; } -/* - * SLIDE STEP STYLES - * - * inspired by: http://html5slides.googlecode.com/svn/trunk/styles.css - * - * ;) - */ - -.slide { - display: block; - - width: 900px; - height: 700px; - - padding: 40px 60px; - - border-radius: 10px; - - background-color: white; - - box-shadow: 0 2px 6px rgba(0, 0, 0, .1); - border: 1px solid rgba(0, 0, 0, .3); - - font-family: 'Open Sans', Arial, sans-serif; - - color: rgb(102, 102, 102); - text-shadow: 0 2px 2px rgba(0, 0, 0, .1); - - font-size: 30px; - line-height: 36px; - letter-spacing: -1px; -} +/* + Now, when we have all the steps styled let's give users a hint how to navigate + around the presentation. + + The best way to do this would be to use JavaScript, show a delayed hint for a + first time users, then hide it and store a status in cookie or localStorage... + + But I wanted to have some CSS fun and avoid additional scripting... + + Let me explain it first, so maybe the transition magic will be more readable + when you read the code. + + First of all I wanted the hint to appear only when user is idle for a while. + You can't detect the 'idle' state in CSS, but I delayed a appearing of the + hint by 5s using transition-delay. + + You also can't detect in CSS if the user is a first-time visitor, so I had to + make an assumption that I'll only show the hint on the first step. And when + the step is changed hide the hint, because I can assume that user already + knows how to navigate. + + To summarize it - hint is shown when the user is on the first step for longer + than 5 seconds. + + The other problem I had was caused by the fact that I wanted the hint to fade + in and out. It can be easily achieved by transitioning the opacity property. + But that also meant that the hint was always on the screen, even if totally + transparent. It covered part of the screen and you couldn't correctly clicked + through it. + Unfortunately you cannot transition between display `block` and `none` in pure + CSS, so I needed a way to not only fade out the hint but also move it out of + the screen. + + I solved this problem by positioning the hint below the bottom of the screen + with CSS transform and moving it up to show it. But I also didn't want this move + to be visible. I wanted the hint only to fade in and out visually, so I delayed + the fade in transition, so it starts when the hint is already in its correct + position on the screen. + + I know, it sounds complicated ... maybe it would be easier with the code? +*/ -.slide q { - display: block; +.hint { + /* + We hide the hint until presentation is started and from browsers not supporting + impress.js, as they will have a linear scrollable view ... + */ + display: none; + + /* + ... and give it some fixed position and nice styles. + */ + position: fixed; + left: 0; + right: 0; + bottom: 200px; + + background: rgba(0,0,0,0.5); + color: #EEE; + text-align: center; + font-size: 50px; - line-height: 72px; - - margin-top: 100px; -} - -.slide q strong { - white-space: nowrap; -} - - -/* IMPRESS NOT SUPPORTED STYLES */ - -.fallback-message { - font-family: sans-serif; - line-height: 1.3; + padding: 20px; - display: none; - width: 780px; - padding: 10px 10px 0; - margin: 20px auto; + z-index: 100; + + /* + By default we don't want the hint to be visible, so we make it transparent ... + */ + opacity: 0; + + /* + ... and position it below the bottom of the screen (relative to it's fixed position) + */ + -webkit-transform: translateY(400px); + -moz-transform: translateY(400px); + -ms-transform: translateY(400px); + -o-transform: translateY(400px); + transform: translateY(400px); - border-radius: 10px; - border: 1px solid #E4C652; - background: #EEDC94; + /* + Now let's imagine that the hint is visible and we want to fade it out and move out + of the screen. + + So we define the transition on the opacity property with 1s duration and another + transition on transform property delayed by 1s so it will happen after the fade out + on opacity finished. + + This way user will not see the hint moving down. + */ + -webkit-transition: opacity 1s, -webkit-transform 0.5s 1s; + -moz-transition: opacity 1s, -moz-transform 0.5s 1s; + -ms-transition: opacity 1s, -ms-transform 0.5s 1s; + -o-transition: opacity 1s, -o-transform 0.5s 1s; + transition: opacity 1s, transform 0.5s 1s; } -.fallback-message p { - margin-bottom: 10px; -} +/* + Now we 'enable' the hint when presentation is initialized ... +*/ +.impress-enabled .hint { display: block } -.impress-disabled .step, -.impress-not-supported .step { - position: relative; +/* + ... and we will show it when the first step (with id 'bored') is active. +*/ +.impress-on-bored .hint { + /* + We remove the transparency and position the hint in its default fixed + position. + */ opacity: 1; - margin: 20px auto; + + -webkit-transform: translateY(0px); + -moz-transform: translateY(0px); + -ms-transform: translateY(0px); + -o-transform: translateY(0px); + transform: translateY(0px); + + /* + Now for fade in transition we have the oposite situation from the one + above. + + First after 4.5s delay we animate the transform property to move the hint + into its correct position and after that we fade it in with opacity + transition. + */ + -webkit-transition: opacity 1s 5s, -webkit-transform 0.5s 4.5s; + -moz-transition: opacity 1s 5s, -moz-transform 0.5s 4.5s; + -ms-transition: opacity 1s 5s, -ms-transform 0.5s 4.5s; + -o-transition: opacity 1s 5s, -o-transform 0.5s 4.5s; + transition: opacity 1s 5s, transform 0.5s 4.5s; } -.impress-not-supported .fallback-message { - display: block; -} +/* + And as the last thing there is a workaround for quite strange bug. + It happens a lot in Chrome. I don't remember if I've seen it in Firefox. + + Sometimes the element positioned in 3D (especially when it's moved back + along Z axis) is not clickable, because it falls 'behind' the <body> + element. + + To prevent this, I decided to make <body> non clickable by setting + pointer-events property to `none` value. + Value if this property is inherited, so to make everything else clickable + I bring it back on the #impress element. + + If you want to know more about `pointer-events` here are some docs: + https://developer.mozilla.org/en/CSS/pointer-events + + There is one very important thing to notice about this workaround - it makes + everything 'unclickable' except what's in #impress element. + + So use it wisely ... or don't use at all. +*/ +.impress-enabled { pointer-events: none } +.impress-enabled #impress { pointer-events: auto } +/* + There is one funny thing I just realized. + + Thanks to this workaround above everything except #impress element is invisible + for click events. That means that the hint element is also not clickable. + So basically all of this transforms and delayed transitions trickery was probably + not needed at all... + + But it was fun to learn about it, wasn't it? +*/ + +/* + That's all I have for you in this file. + Thanks for reading. I hope you enjoyed it at least as much as I enjoyed writing it + for you. +*/
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