<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Border Color</title>
  </head>
<body>
  <p>A solid red border</p>
</body>
</html>
p {
  border-style: solid;
  border-color: #E21717;
}

External CSS

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External JavaScript

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