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In Pictures: 10 tips for giving killer presentatio...
3. Edit background colors and text with the Theme Wizard.
Once you've picked a template for your prezi, you can customize it further by right-clicking anywhere within the prezi window and clicking "Change background." This command opens the Theme Wizard. From this menu, you can edit the colors of individual theme elements like shapes, borders and text.
If you need even more customization, click the "Use the Prezi CSS Editor" option at the bottom of the Theme Wizard menu to custom code your prezi.
In Pictures: 10 tips for giving killer presentations with the new Prezi