only when the layers contents exceed its boundaries. (This feature does not currently display in the Dreamweaver Workspace.) _ Placement: Defines the size and location of an element layer within its containing element. For example, you can set the right edge of the element to line up with the right edge of the element that contains it. The default values are measured in pixels, but you can also use pc (picas), pt (points), in (inches), mm (millimeters), cm (centimeters), or % (percentage of the parents value). _ Clip: When the content of an element overflows the space allotted and you set the Overflow property to scroll or auto, you can set the clip settings to specify which part of the layer is visible by controlling which part of the layer is cropped if it doesnt fit in the display area. The Extensions category Extensions (see Figure 8-19) include filters and cursor options: _ Pagebreak: Inserts a point in a page where a printer sees a page break. This option allows you to control the way the document is printed. _ Cursor: Defines the type of cursor that appears when a user moves the cursor over an element. Figure 8-19: The Extensions category in the CSS Rule Definition dialog box. 228 Part III: Advancing Your Site _ Filter: Enables you to apply to elements special effects such as drop shadows, motion blurs, and many others. These are only visible in Microsoft Internet Explorer. Using External Style Sheets The first part of this chapter focuses on using CSS only in the context of internal style sheets. Internal style sheet information is stored in the HTML code of the document youre working on and applies to only the current document. If you want to create styles you can share among documents, you need to use external style sheets. External style sheets enable you to create styles you can apply to pages throughout a Web site by storing the style sheet information in a separate text page that can be linked to from any HTML document. External style sheets (also called linked style sheets) are where you can realize the greatest timesavings with CSS. You can define styles for common formatting options used throughout an entire site, such as headlines, captions, and even images, which makes applying multiple formatting options to elements fast and easy. Big news- and magazine-type Web sites often use external style sheets because they need to follow a consistent look and feel throughout the site, even when many people are working on the same site. Typing styles to HTML tags via an external style sheet is a foolproof way of making sure that everyone creating content for your Web site ends up with pages that look the same. Using external style sheets also makes global changes easier because when you change the external style sheet, you globally change every element to which you applied the style throughout the site. Creating an external style sheet You create external style sheets almost exactly the same way you create internal style sheets, except that external style sheets need to be saved as separate files. When you use Dreamweaver to create an external style sheet,