<SyntaxDefinition name="C#"
        xmlns="http://icsharpcode.net/sharpdevelop/syntaxdefinition/2008">
  <Color name="String" foreground="#4557de" />

  <!-- This is the main ruleset. -->
  <RuleSet>

    <Span color="String">
      <Begin>'</Begin>
      <End>'</End>
      <RuleSet>
        <!-- nested span for escape sequences -->
        <Span begin="\\" end="." />
      </RuleSet>
    </Span>

    <Keywords fontWeight="bold" foreground="#1a97e6">
      <Word>if</Word>
      <Word>else</Word>
      <!-- ... -->
    </Keywords>

    <!-- Digits -->
    <Rule foreground="#bfb2b0">
      \b(?im)[{(]?[0-9A-F]{8}[-]?(?:[0-9A-F]{4}[-]?){3}[0-9A-F]{12}[)}]?  # guid
      |\b[0-9]+
    </Rule>
  </RuleSet>
</SyntaxDefinition>