border-color

The border-color CSS property is a shorthand for setting the color of the four sides of an element’s border: border-top-color, border-right-color, border-bottom-color, border-left-color

Values

color Is a <color> denoting the color to apply to all four edges. It is used only in the one-value syntax.
horizontal Is a <color> denoting the color to apply to all horizontal edges, that is the top and bottom edges. It is used only in the two-value syntax.
vertical Is a <color> denoting the color to apply to all vertical edges, that is the right and left edges. It is used only in the two- and three-value syntaxes.
top Is a <color> denoting the color to apply to the top edge. It is used only in the three- and four-value syntaxes.
bottom Is a <color> denoting the color to apply to the bottom edge. It is used only in the three- and four-value syntaxes.
right Is a <color> denoting the color to apply to the top edge. It is used only in the four-value syntax.
left Is a <color> denoting the color to apply to the top edge. It is used only in the four-value syntax.
inherit Is a keyword indicating that all four values are inherited from their parent’s element calculated value

Example

<!DOCTYPE HTML>
<html>
    <head>
        <title>CSS Tutorials</title>
        <style>
            div {
                border-style: ridge dashed solid;
                border-color: orange blue;
                width: 200px;
                height: 200px;
            }
        </style>
    </head>
    <body>
        <div>
        </div>
    </body>
</html>