Css

From miki
Jump to navigation Jump to search

References

Specifications
W3Schools
Tutorials
Compatibility
Tools
WTF

Quick reference

Fonts

p { font-size: 30px; }
p { font-size: 12pt; }
p { font-size: 100%; }
p { font-size: 1.5em; }
Set the font size

Syntax

External CSS

External CSS is a file that contains only CSS code and is saved with a .css file extension. This CSS file is then referenced in your HTML using the <link> instead of <style>.

Content of file test.css: 

body{ background-color: gray;} 
p { color: blue; } 
h3{ color: white; }

Example html file using the stylesheet above: 

<html>
<head>
  <link rel="stylesheet" type="text/css" href="test.css" />
</head>
<body>
  <h3> A White Header </h3>
  <p> This paragraph has a blue font.  
  The background color of this page is gray because we changed it with CSS! </p>
</body>
</html>

Internal CSS

When using internal CSS, you must add a new tag, <style>, inside the <head> tag. 

<html>
<head>
  <style type="text/css">
    p {color: white; }
    body {background-color: black; }
  </style>
</head>
<body>
  <p>White text on a black background!</p>
</body>
</html>

Inline CSS

To add style to a given HTML element, just specify the desired CSS properties with the HTML style attribute: 

<p style="background: blue; color: white;">A new background and font color with inline CSS</p>

Selectors

See the reference here.

Pattern Meaning Described in section
* Matches any element. Universal selector
E Matches any E element (i.e., an element of type E). Type selectors
E F Matches any F element that is a descendant of an E element. Descendant selectors
E > F Matches any F element that is a child of an element E. Child selectors
E:first-child Matches element E when E is the first child of its parent. The :first-child pseudo-class
E:link E:visited Matches element E if E is the source anchor of a hyperlink of which the target is not yet visited (:link) or already visited (:visited). The link pseudo-classes
E:active E:hover E:focus Matches E during certain user actions. The dynamic pseudo-classes
E + F Matches any F element immediately preceded by a sibling element E. Adjacent selectors
E[foo] E[foo="warning"] E[foo~="warning"] Matches any E element whose "foo" attribute set OR value is exactly equal to "warning" OR value is a list of space-separated values, one of which is exactly equal to "warning". Attribute selectors
DIV.warning Language specific. (In HTML, the same as DIV[class~="warning"].) Class selectors
E#myid Matches any E element with ID equal to "myid". ID selectors

How Cascading Works

Quick and simplified overview:

  • First, inherited properties (from parent object)
  • Second, properties for that objects, taking account override (according to property specificities).
  • !important keyword, etc.

More information:

Tips

Using Opera DragonFly

Opera DragonFly is a powerful tool to write / debug CSS:

  • Browse rapidly and easily through all CSS properties of any visual object, and get detailed view on how they are computed.
  • Easy access to CSS property documentation.

Font size

  • Use property font-size to define the font size of a given visual element.

Short reminder on font sizes:

  • pt (points) is defined as 1/72 of screen inch. For 96 dpi resolution (i.e. 96 pixels per inch), we have 1pt=1.333px.
  • px (pixel) the smallest graphic element on the screen. The number of pixels (or dots) per inch (DPI) gives the screen resolution. Nowadays DPI is usually equal to 96.
  • em (for the letter M) is a unit of width in the field of typography, equal to the currently specified point size. Originally 1em was the width of the capital M in the current font.

Some usual values (see also pxtoem.com):

DPI 1 pt 12pt (1 pica)
72 1px 12px
96 1.333px 16px

Note that em is a relative font size. It sets the size of current elements in function of the size of the containing parent. So 1.2em means 20% current font size of parent object.

Inlining tables

Use display:inline-block or display:inline-table to have table element flowed like regular text. Use vertical-align:middle to change vertical alignment. 

some text
<table style="display:inline-block; vertical-align:middle;">
  <tr><td>4<br/>3<br/>2<br/>1<br/></td></tr>
  <tr><td>abcd</td></tr>
</table>
some text

Web fonts

web fonts allows for rendering pages using fonts that are not available on the client, but downloaded from the server. It uses CSS3 tag @font-face.

Reference:

  • If uploaded fonts contains special characters, select No subsetting, or font squirrel will strip these glyphs from the font package.
  • Using @font-face (CSS tricks to maximize browser compatibility, thorought analysis)
Minimum code

Add to your stylesheet: 

@font-face {
    font-family: 'Chess Merida Unicode';
    src: url('chess_merida_unicode.ttf');
}

Note: If the path does not work, try with a relative path instead (url('./chess_merida_unicode.ttf')), but it should works without it [1]. Also, simple or double quotes in url are optional.

Multi-file for several styles

From SO: 

@font-face {
    font-family: "DejaVu Sans";
    src: url("fonts/DejaVuSans.ttf");
}
@font-face {
    font-family: "DejaVu Sans";
    src: url("fonts/DejaVuSans-Bold.ttf");
    font-weight: bold;
}
@font-face {
    font-family: "DejaVu Sans";
    src: url("fonts/DejaVuSans-Oblique.ttf");
    font-style: italic, oblique;
}
@font-face {
    font-family: "DejaVu Sans";
    src: url("fonts/DejaVuSans-BoldOblique.ttf");
    font-weight: bold;
    font-style: italic, oblique;
}
Webfont on remote server (doesn't work on FF it seems)

Add to your stylesheet: 

@import url(//fonts.googleapis.com/css?family=Open+Sans);

Then we can use it to style elements: 

body {
  font-family: 'Open Sans', sans-serif;
}
Troubleshooting
  • Fonts must be in same directory or subtree. Not on another site or up tree! [2]
@font-face {
    font-family: 'Chess Merida Unicode';
    src: url('../chess_merida_unicode.ttf');      # BAD! THIS WILL FAIL IN FIREFOX
}

Examples

/* install_log class for install log table */
table.install_log td:first-child
{
	width:7.5em;
	font-size: x-small;
}
table.install_log td:first-child:before
{
	content:url(/miki/skins/monobook/bullet.gif);
	margin-right:0.6em;
}
Retrieved from "https://miki.immie.org/mediawiki/index.php?title=Css&oldid=16786"