As a child of head and in Flow content. The trigger element associates an event from a specified source object observer with a desired action to be performed with a specified target object ref. The semantics of the defined action values are:
Real numbers and integers are specified in decimal notation only. Note that many properties that allow an integer or real number as a value actually restrict the value to some range, often to a non-negative value. After a zero length, the unit identifier is optional. Some properties allow negative length values, but this may complicate the formatting model and there may be implementation-specific limits.
If a negative length value cannot be supported, it should be converted to the nearest value that can be supported.
If a negative length value is set on a property that does not allow negative length values, the declaration is ignored. In cases where the used length cannot be supported, user agents must approximate it in the actual value.
There are two types of length units: Relative length units specify a length relative to another length property.
Style sheets that use relative units can more easily scale from one output environment to another. The exception is when 'em' occurs in the value of the 'font-size' property itself, in which case it refers to the font size of the parent element.
It may be used for vertical or horizontal measurement. This unit is also sometimes called the quad-width in typographic texts. The 'ex' unit is defined by the element's first available font.
The exception is when 'ex' occurs in the value of the 'font-size' property, in which case it refers to the 'ex' of the parent element. The 'x-height' is so called because it is often equal to the height of the lowercase "x".
However, an 'ex' is defined even for fonts that do not contain an "x". The x-height of a font can be found in different ways. Some fonts contain reliable metrics for the x-height.
If reliable font metrics are not available, UAs may determine the x-height from the height of a lowercase glyph. One possible heuristic is to look at how far the glyph for the lowercase "o" extends below the baseline, and subtract that value from the top of its bounding box. In the cases where it is impossible or impractical to determine the x-height, a value of 0.
On the other hand: When specified for the root of the document tree e. Child elements do not inherit the relative values specified for their parent; they inherit the computed values. In the following rules, the computed 'text-indent' value of "h1" elements will be 36px, not 45px, if "h1" is a child of the "body" element.
They are mainly useful when the output environment is known. The absolute units consist of the physical units in, cm, mm, pt, pc and the px unit: For a CSS device, these dimensions are either anchored i by relating the physical units to their physical measurements, or ii by relating the pixel unit to the reference pixel.
For print media and similar high-resolution devices, the anchor unit should be one of the standard physical units inches, centimeters, etc. For lower-resolution devices, and devices with unusual viewing distances, it is recommended instead that the anchor unit be the pixel unit.
For such devices it is recommended that the pixel unit refer to the whole number of device pixels that best approximates the reference pixel.CSS Templates CSS Examples CSS Quiz CSS Exercises CSS Certificate Different types of cursors Advanced - Create link boxes Advanced - Create link boxes with borders.
Link properties explained.
|Difference Between Serif and Sans-serif Fonts||Inheritance[ edit ] Inheritance is a key feature in CSS; it relies on the ancestor-descendant relationship to operate. Inheritance is the mechanism by which properties are applied not only to a specified element, but also to its descendants.|
CSS Lists. All the different list item markers in lists Set an image as the list-item marker. Feb 23, · The contents of my CSS pages and browser compatibility. This is the old table.I’m slowly moving towards the new tables, which feature greatly extended tests and full mobile browser yunusemremert.com I publish a new table I remove the entries on this page.
Oct 11, · This specification, EPUB Content Documents , defines profiles of HTML5, SVG, and CSS for use in the context of EPUB® Publications.
This specification is one of a family of related specifications that compose EPUB 3, the third major revision of an . Oct 09, · Other types of metadata. As you travel around the web, you'll find other types of metadata, too. A lot of the features you'll see on websites are proprietary creations, designed to provide certain sites (such as social networking sites) with specific pieces of information they can use.
CSS Attribute Selectors CSS [attribute|="value"] Selector. The [attribute|="value"] selector is used to select elements with the specified attribute starting with the specified value.
The following example selects all elements with a . Syntax. This section describes a grammar (and forward-compatible parsing rules) common to any level of CSS (including CSS ). Future updates of CSS will adhere to this core syntax, although they may add additional syntactic constraints.