Lesson 23 what is wrong please help


#1

I have no clue what is wrong please help

<!DOCTYPE html>
<html>
	<head>
		<link type="text/css" rel="stylesheet" href="stylesheet.css"/>
		<title>Result</title>
	</head>
	<body>

	<h3 class="fancy"> code </h3>
	<p class="fancy"> code </p>
	<p id="serious"> code </p>
    <p> help </p>
	    
	</body>
</html>


.fancy {
    font-family:cursive;
    color:violet;
}
#serious {
    font-family:Courier;
    color:#8C8C8C;
}
body :nth-child(4) {
    font size: 26px;
}

#2

font-size is one word with a hyphen in between


#3

thank you so much i had been looking at that for hours


#4