PHP Error Message Color [duplicate]

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• how to style php echo output 6 answers

As I mention in the title I am facing a problem to change the error message color to red inside a PHP code, and here is the code:

 if(mysql_num_rows($r2)>0){

    $msg2="Email already exist";

    echo $msg2;
  }

Could anyone help me to modify it ?

All answers are appreciated...