The CSS Styles panel
The CSS Styles panel lets you track the CSS rules and properties affecting a currently selected page element (Current mode), or the rules and properties affecting an entire document (All mode). A toggle button at the top of the CSS Styles panel lets you switch between the two modes. The CSS Styles panel also lets you modify CSS properties in both All and Current mode.
You can resize any of the panes by dragging the borders between the panes.
In Current mode, the CSS Styles panel displays three panes: a Summary for Selection pane that displays the CSS properties for the current selection in the document, a Rules pane that displays the location of selected properties (or a cascade of rules for the selected tag, depending on your selection), and a Properties pane that lets you edit CSS properties for the rule defining the selection.
In All mode, the CSS Styles panel displays two panes: an All Rules pane (on top), and a Properties pane (on bottom). The All Rules pane displays a list of rules defined in the current document as well as all rules defined in style sheets attached to the current document. The Properties pane lets you edit CSS properties for any selected rule in the All Rules pane.
Any changes you make in the Properties pane are applied immediately, letting you preview your work as you go.
For more information about the CSS Styles panel, see About the CSS Styles panel in Using Dreamweaver.