Percentage values refer to the width of the parent element.

Using any one of these properties allows you to set a margin on that side only, without directly affecting any of the other margins.

It's possible to use more than one of these single-side properties in a single rule; for example:

H2 {margin-left: 3em; margin-bottom: 2em; margin-right: 0; margin-top: 0;}

As we see in Figure 7-15, the margins were set as we wanted them. wohnung mieten

Sunday 25th of June 2017 03:51:37 AM

CSS Style Guide

XHTML: Benefits

Converting from HTML to XHTML is easy, and provides the library with several immediate and long–term benefits:

A painless transition to more advanced technology
The web is moving to XML, a powerfully enabling technology. Writing well–formed, valid XHTML pages is the easiest way to begin this transition. All it takes is learning a few simple rules of XHTML markup.
Cleaner, more logical markup
XHTML brings uniformity to document structure. The rules of XHTML help restore the structural integrity of documents that was lost during the web’s rapid commercial expansion between 1994 and 2001. This is critical for large organizations such as ours, whose web pages must interface with logically–marked–up documents in legacy systems and databases.
Increased interoperability
Unlike old–style HTML pages, valid, well–formed XHTML documents can easily be “transported” to wireless devices, Braille readers and other specialized web environments. Moreover, XHTML’s insistence on clean, rule–based markup helps us avoid the kind of errors that can make web pages fail even in traditional browsers like Microsoft Internet Explorer, Netscape Navigator, and Opera Software’s Opera browser.
Greater accessibility
Because they follow strict rules and avoid non–standard markup, well–authored XHTML pages are more accessible than old–school HTML pages, helping the library comply with U.S. laws and accessibility guidelines.
« XHTML Section Index | XHTML Authoring Tips 'n Tools »

P {margin-left: 5em; position: relative;} <P> Lorem ipsum, dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut <SPAN CLASS="change">***</SPAN> laoreet dolore magna aliquam erat volutpat.</P>

While this does rely on inserting an extra element, the advantage is that the SPAN can be placed anywhere in the paragraph and still have the result depicted in Figure 9-21.

Figure 9-21

Figure 9-21. Setting a "change bar" with absolute positioning

However, maybe we'd like to place the change marker next to

Now let's place the pictures. There are two of them, both in the first column, so that makes things a lot easier. Obviously, they're left-floating images. The interesting part will be recreating the way they hang out into the blank space to the left of the column.

If we just give these pictures the style float: left, they'll be completely contained within the user. This would lead to a situation like that illustrated by Figure 9-10.

Figure 9-10

Figure 9-10. Clipping content with overflow

Finally, there is overflow: auto. This allows user agents to determine what behavior to use, although they are encouraged to provide a scrolling mechanism when necessary. This is a potentially useful way to use overflow, since user agents could interpret it to mean "provide scrollbars only when needed." (They maytheir part, this represents a remarkable commitment to standardssupport, even though it might confuse or annoy many web designers.

The second problem is a little more fundamental: there are nostandard color values for these names. Declaring that an elementshould be colored orange doesn't mean thatdifferent browsers, or even the same browser running on differentplatforms, will produce exactly the same shade of orange. With thesixteen standard colors, there is at least some hope that they willappear as similar as possible, because the color values for these