color: -1 color

Quick answer：

The term 'color: -1 color' seems to refer to a color value set to -1, which is not a standard RGB, HSL, or hexadecimal value used in web design or color theory. It could be a placeholder or a custom value in a specific context. In web design, colors are typically represented by hexadecimal codes, RGB, or HSL values. For instance, black is represented as #000000, RGB(0,0,0), or HSL(0,0%,0%).