Using resources to define global styles
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"> <Page.Resources> <SolidColorBrush x:Key="RedBrush" Color="red"/> <SolidColorBrush x:Key="BlueBrush" Color="blue"/> </Page.Resources> <StackPanel> <Button Background="{StaticResource RedBrush}" /> <Ellipse Fill="{StaticResource BlueBrush}" Margin="40" Width="15" Height="25"/> </StackPanel> </Page>