A Qt style sheet is not CSS although it has many similarities. Text in a different colour is trivial and you probably want to tweak the selection highlight colour also:
Qt Code:
  1. #include <QtGui>
  2. int main(int argc, char **argv)
  3. {
  4. QApplication app(argc, argv);
  5. l.setStyleSheet(
  6. "QLineEdit { "
  7. "color: red; background-color: white; "
  8. "selection-color: white; selection-background-color: red; }" );
  9. l.show();
  10. return app.exec();
  11. }
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As far as I can see Qt Style Sheets do not have any equivalent of the CSS3 text-shadow property.