Add RGB_COLOR_HSB to lighting documentation

docs/docs/behaviors/lighting.md

@@ -22,7 +22,7 @@ This will allow you to reference the actions defined in this header such as `RGB
 Here is a table describing the action for each define:
 
 | Define          | Action                                                                                         |
-| --------- | --------------------------------------------------------- |
+| --------------- | ---------------------------------------------------------------------------------------------- |
 | `RGB_TOG`       | Toggles the RGB feature on and off                                                             |
 | `RGB_HUI`       | Increases the hue of the RGB feature                                                           |
 | `RGB_HUD`       | Decreases the hue of the RGB feature                                                           |
@@ -34,6 +34,7 @@ Here is a table describing the action for each define:
 | `RGB_SPD`       | Decreases the speed of the RGB feature effect's animation                                      |
 | `RGB_EFF`       | Cycles the RGB feature's effect forwards                                                       |
 | `RGB_EFR`       | Cycles the RGB feature's effect reverse                                                        |
+| `RGB_COLOR_HSB` | Sets a specific [HSB (HSV)](https://en.wikipedia.org/wiki/HSL_and_HSV) value for the underglow |
 
 ## RGB Underglow
 
@@ -42,10 +43,31 @@ The "RGB underglow" behavior completes an RGB action given on press.
 ### Behavior Binding
 
 - Reference: `&rgb_ug`
-- Parameter: The RGB action define, e.g. `RGB_TOG` or `RGB_BRI`
+- Parameter #1: The RGB action define, e.g. `RGB_TOG` or `RGB_BRI`
+- Parameter #1: Only applies to `RGB_COLOR_HSB` and is the HSB values of the color to set within parenthesis and separated by a common (see below for an example)
 
-Example:
+:::note HSB Values
 
-```
-&rgb_ug RGB_TOG
-```
+When specifying HSB values you'll need to use `RGB_COLOR_HSB(h, s, b)` in your keymap file. See below for an example.
+
+Value Limits:
+
+- Hue values can _not_ exceed 360 (degrees)
+- Saturation values can _not_ exceed 100 (percent)
+- Brightness values can _not_ exceed 100 (percent)
+
+:::
+
+### Examples
+
+1. Toggle underglow on/off
+
+   ```
+   &rgb_ug RGB_TOG
+   ```
+
+1. Set a specific HSB color (green)
+
+   ```
+   &rgb_ug RGB_COLOR_HSB(128,100,100)
+   ```