thanks for the link jpn.

in the link the code sets pushbutton to red color.
Qt Code: 
  1. button->setStyleSheet("color: #0000dd; background-color: red;");
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but even if we use
Qt Code: 
  1. button->setStyleSheet("background-color: red;");
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this we get the same ,then what does color: #0000dd signify and do we really need it. i have gone through the docs(The Style Sheet Syntax) and i have not found any thing like this.