<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
<style>
div {
padding: 10px;
width: 50%;
border: solid #666;
border-top-color: rgb(142, 191, 66);
}
</style>
</head>
<body>
<div>Border-top-color property with a RGB value.</div>
</body>
</html>