index.html (file) <!DOCTYPE html> <html> 	<head> 		<link type="text/css" rel="stylesheet" href="stylesheet.css"/> 	</head> 	<body> 	    <h1> Key:</h1> 	    <div id="one"></div>  	    <div id="space">Data will be used for this purpose</div> 	    <div id="two"><p>opt-out</p></div>  	    <div id="space">Data will be used for this purpose,but you may opt out of use</div>         <div id="three"></div></div>          <div id="space">Data will not be used for this purpose</div> 	    <div id="four"><p>opt-in</p></div> 	    <div id="space">Data will not be used for this purpose,but you may opt in of use</div> 	</body> </html>                          stylesheet.css (file)  h1 {     font-family:Sans-serif; }  div { 	height: 3em; 	width: 5em; 	border: 0.1em solid black; }  div p {     text-align:center;     color:white;     font-size: 1em;      }  #space{ 	height: 3em; 	width: 30em; 	border: .1em solid black; 	border-radius: 5px;      }  #one { 	background-color: maroon; 	float:left; }  #two { 	background-color: maroon; 	float:left;  }  #three { 	background-color: green; 	float:left;  }  #four { 	background-color: green; float:left; }