The ABCs of CSS You've Likely Never Used

That Conference 2017

Transcript

1. The ABCs of CSS Properties You’ve Likely Never Used (Well, Mostly!) Alicia Sedlock | @aliciability
2. Hi!
4. What’s your favorite CSS property or module?
6. There’s a lot of CSS I don't know.
7. A additive-symbols “… specify symbols when the value of a counter system descriptor is additive.”
8. @counter-style custom-counter { system: additive;
 additive-symbol: I 1; }
 .list { list-style: custom-counter;
 
 }
9. @counter-style custom-counter { system: additive;
 additive-symbol: “>” 3; }
 .list { list-style: customer-counter;
 
 }
10. @counter-style custom-counter { system: additive;
 additive-symbol: “X” 10, “V” 5, “I” 1; }

11. B ::backdrop
 
 “…is a box rendered immediately below any element rendered in fullscreen mode.”
12. dialog { /* some dialog styles */ } dialog::backdrop {
 
 background: black;
 opacity: .5;
 
 }
14. C caret-color
 
 “…sets the color of the caret in an element.”
15. input.custom { caret-color: red; }
17. D :default
 
 “…represents any user interface element that is the default among a group of similar elements.”
18. :default { background-color: pink; } <form> <input type=“button” value=“Button” /> <input type=“submit” /> <input type=“reset” /> </form>
20. E :empty
 
 “ ..any element that has no children at all.”
21. div {
 
 background: lightblue;
 
 } div:empty {
 
 background: pink;
 
 } <div><!— No content —></div> <div>Hello world!</div> <div>
 <!— No content —>
 </div>
23. F ::first-letter
 
 “…applies styles to the first letter of the first line of a block-level element…”
24. p::first-letter {
 
 color: red;
 font-size: 3em;
 font-weight: bold;
 
 }
 
 <p>The quick brown fox</p>
25. p::first-letter {
 
 color: red;
 font-size: 3em;
 font-weight: bold;
 
 }
 
 <p>
 <img src=“fox.jpg” />
 The quick brown fox
 </p>
26. G grayscale()
27. .fox1 { filter: grayscale(.95); } .fox2 { filter: grayscale(.55); } .fox3 { filter: grayscale(.15); }
28. H hyphens
 
 “…how words should be hyphenated when text wraps across multiple lines.”
29. <p>That Conference is extreme&shy;ly rad!</p> p {
 hyphens: none;
 width: 55px;
 }
30. <p>That Conference is extreme&shy;ly rad!</p> p {
 hyphens: manual;
 width: 55px;
 }
31. <p>That Conference is extreme&shy;ly rad!</p> p {
 hyphens: auto;
 width: 55px;
 }
32. I :in-range
 
 “…matches when the value currently contained inside an <input> element is inside the range limits specified by the min and max attributes.”
34. <label>Enter a number 1-10</label>
 <input type="number" min="1" max="10" value="12" />
 
 input:in-range {
 background-color: rgba(0, 255, 0, 0.25);
 }
 
 input:out-of-range {
 background-color: rgba(255, 0, 0, 0.25);
 border: 2px solid red;
 }
36. J justify-content
 ONLY ENTRY
 
 “…defines how the browser distributes space between and around content items along the main axis of their container.”
37. .container {
 display: flex;
 justify-content: <value>;
 } <div class=“container”>
 <div><!— Content! —></div>
 <div><!— Content! —></div>
 <div><!— Content! —></div>
 </div>
38. .container {
 display: flex;
 justify-content: flex-start;
 } <div class=“container”>
 <div><!— Content! —></div>
 <div><!— Content! —></div>
 <div><!— Content! —></div>
 </div>
39. .container {
 display: flex;
 justify-content: flex-end;
 } <div class=“container”>
 <div><!— Content! —></div>
 <div><!— Content! —></div>
 <div><!— Content! —></div>
 </div>
40. .container {
 display: flex;
 justify-content: center;
 } <div class=“container”>
 <div><!— Content! —></div>
 <div><!— Content! —></div>
 <div><!— Content! —></div>
 </div>
41. .container {
 display: flex;
 justify-content: space-around;
 } <div class=“container”>
 <div><!— Content! —></div>
 <div><!— Content! —></div>
 <div><!— Content! —></div>
 </div>
42. .container {
 display: flex;
 justify-content: space-between;
 } <div class=“container”>
 <div><!— Content! —></div>
 <div><!— Content! —></div>
 <div><!— Content! —></div>
 </div>
43. K khz
 
 “…represents a frequency dimension, such as the pitch of a speaking voice.”
44. p.low { pitch: 105Hz; } em.high { pitch: 135Hz; }
45. L :lang
 
 “…matches elements based on the language the element is determined to be in.”
46. <html lang=“en”></html>
47. <div lang=“en”>Hello, world!</div> <div lang=“fr”>Bonjour, le monde!</div> <div lang=“de”>Hallo, Welt!</div>
48. 
 :lang(en) { border: 1px solid red; } :lang(fr) { border: 1px solid blue; } :lang(de) { border: 1px solid black; }
49. M max-zoom
 
 “…sets the maximum zoom factor of a document defined by the @viewport at- rule."
50. * { max-zoom: 150%;
 
 max-zoom: 2.0; }
51. N negative
 
 “…alters the representation of negative counter values, by providing a way to specify symbols to be appended or prepended to the counter representation when the value is negative.”
52. <ul class="list" start="-3"> <li>One</li> <li>Two</li> <li>Three</li> <li>Four</li> <li>Five</li> </ul>
53. @counter-style negative-counter { system: numeric;
 symbols: "0" "1" "2" "3" "4" "5" "6" "7" "8" "9";
 negative: "(-" ")"; } .list { list-style: negative-counter; }
55. O object-fit
 
 “…how a replaced element, such as an <img> or <video>, should be resized to fit its container.”
56. /* Base styles for examples */
 img { width: 400px; height: 500px; border: 5px solid pink; object-fit: <value>; }
62. P pointer-events
 
 “…specifies under what circumstances a particular graphic element can become the target of mouse events.”
63. div {
 
 pointer-events: none; }
64. <div> Lorem ipsum dolor sit amet… </div> <div class="overlay"> I am an overlay. Try selecting the text behind me. </div>
65. .overlay { position: absolute; top: 0; left: 40%; background: rgba(0,0,0,.75); height: 200px; width: 250px; color: white; padding: 1em; pointer-events: auto; }
66. pointer-events: auto
67. pointer-events: none
68. pointer-events: visiblePainted;
 pointer-events: visibleFill;
 pointer-events: visibleStroke;
 pointer-events: visible;
 pointer-events: painted;
 pointer-events: fill;
 pointer-events: stroke;
 pointer-events: all;
69. Q quotes
 
 “…indicates how user agents should render quotation marks.”
70. <span>According to Groot, <q>I am Groot.</q>.</span> 
 q { quotes: "**" “**”; } q:before { content: open-quote; } q:after { content: close-quote; }
71. <span>Peter Quill says <q>I'm pretty sure the answer is <q>I am Groot</q>.</q></span> 
 q { quotes: ’””’ ‘“”’ “‘’” “‘’”; } q:before { content: open-quote; } q:after { content: close-quote; }
72. R revert
 
 “…rolls back the cascade so that a property takes on the value it would have had if there were no styles in the current style origin"
74. S suffix
 
 “…specifies a symbol that will be appended to the marker representation.”
75. <ul class="list"> <li>One</li> <li>Two</li> <li>Three</li> <li>Four</li> <li>Five</li> </ul>
76. @counter-style counter-options { system: fixed;
 symbols: A B C D E F G;
 suffix: “) ”; } .list { list-style: counter-options; }
78. T tab-size
 
 “…used to customize the width of a tab (U+0009) character.”
79. pre { tab-size: 4; /* integer values */
 tab-size: 2;
 tab-size: 10px; /* length values */
 tab-size: 2em; }
80. <pre class=“default"> &#9;This is a line in pre! &#9;CSS is a lot of fun. :) </pre> pre { border: 1px solid black;
 width: 500px; }
81. <pre class=“default"> &#9;This is a line in pre! &#9;CSS is a lot of fun. :) </pre> pre { border: 1px solid black;
 width: 500px;
 tab-size: 4; }
82. <pre class=“default"> &#9;This is a line in pre! &#9;CSS is a lot of fun. :) </pre> pre { border: 1px solid black;
 width: 500px;
 tab-size: 100px; }
83. U unset
 
 “…resets a property to its inherited value if it inherits from its parent, and to its initial value if not.”
84. <p>I want to be blue text!</p> <div class="foo"> <p>I want to be orange text :(</p> </div> <div class="bar"> <p>I don't want to be orange.</p> </div> .foo { color: orange; } .bar { color: green; } p { color: blue; } .bar p { color: unset; }
86. V vw/vh “Equal to 1% of the width/height of the viewport's initial containing block.”
87. W will-change “…provides a way for authors to hint browsers about the kind of changes to be expected on an element, so that the browser can set up appropriate optimizations ahead of time…”
88. div {
 will-change: transform;
 will-change: opacity;
 will-change: contents; /* custom-ident */
 will-change: scroll-behavior; /* custom-ident */
 }
89. A warning on will-change • Intended as a “last resort” - don’t prematurely optimize • Meant to be used sparingly
90. X
 Y
91. * { xtreme: ‘heck-yeah’; }
92. * { yolo: 100; }
93. Z z-index “… specifies the z-order of a positioned element and its descendants.”
 

94. What the heck do I do with this now?
95. Depth of CSS
96. Some of these things are • Experimental technology • In working draft • In initial definition
97. Grid Layout Hype
98. P pointer-events
 
 “…specifies under what circumstances a particular graphic element can become the target of mouse events.”
101. A Challenge
103. Thank you.