Syntax highlighting enables you to apply different colors and some font attributes (bold, Italics, underline) to different PHP syntax elements.
The default elements and their colors are shown below:
Select Windows > Preferences > PHP > Editor > Syntax Coloring. The Syntax Coloring dialog will open.
Open the Content Type's drop down list. Select the Content Type to modify.
To change the Background color, click the Background color rectangle. The Color dialog will open. Select the new Background color and click OK. The new background color will be applied to all backgrounds of that Content Type. The sample code will change according to the changes you have made.
To change the Foreground color, click the Foreground color rectangle. The Color dialog will open. Select the new Foreground color and click OK. The new Foreground color will be applied to all foregrounds of that Content Type. The sample code will change according to the changes you have made
Click Apply / OK to apply the new settings to your PHP code and exit.

Select Windows > Preferences > PHP > Editor > Syntax Coloring. The Syntax Coloring dialog will open.
Open the Content Type's drop down list. Select the Content Type to modify.
Check Bold and/or Italics and/or underline. The sample code will change according to the changes you have made.
Click Apply / OK to apply the new settings to your PHP code and exit.
Select a Content Type and click Reset Default to restore the defaults of the specific Content Type.
Click Reset Defaults (at the bottom right) to restore all defaults.