Workspace options
The Workspace panel of the Options dialog box lets you control the appearance of the Expression Design interface.
Theme You can select a color scheme for the user interface from the Theme list. When you select a theme, the interface updates immediately.
Workspace zoom The panes and panels in Expression Design are resolution independent and can be scaled to any size. To increase the size of your workspace elements, drag the Workspace zoom slider up or to the right; to decrease, drag to the left or down. Alternately, you can click the value to type in a specific zoom amount.