diff --git a/css/impress-demo.css b/css/impress-demo.css
index 1f137cfa1..75fd1ad0a 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
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 (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 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
+ element.
+
+ To prevent this, I decided to make 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.
+*/
\ No newline at end of file