For modifying the outline color, web developers can use the shorthand outline property, which lists all outline values (weight, style, and color) separated by gaps or choose the more specific outline-color property.

Since border sides can all be different, you can use the border-color property and, in clockwise order, specify the color for each side.

What value can the color property take?

• Color name, e.g., yellow
• HEX code, e.g. #FDC500
• RGB code, e.g. rgb(253,197,0)
• HSL - specify a HSL value, like hsl(47, 100%, 50%)
• Transparent