example of alpha channel value

docs/defaults/overlay_variables.md

@@ -21,13 +21,13 @@ Below are the available variables which can be used to customize the file.
 | `horizontal_align`         | **Description:** Controls the Horizontal Alignment of the overlay.<br>**Values:** `left`, `center`, or `right`                                                                                                 |
 | `vertical_offset`          | **Description:** Controls the Vertical Offset of this overlay. Can be a %.<br>**Values:** Number 0 or greater or 0%-100%                                                                                       |
 | `vertical_align`           | **Description:** Controls the Vertical Alignment of the overlay.<br>**Values:** `top`, `center`, or `bottom`                                                                                                   |
-| `back_color`               | **Description:** Controls the Backdrop Color for the Text Overlay.<br>**Values:** Color Hex Code in format `#RGB`, `#RGBA`, `#RRGGBB` or `#RRGGBBAA`                                                           |
+| `back_color`               | **Description:** Controls the Backdrop Color for the Text Overlay.<br>**Values:** Color Hex Code in format `#RGB`, `#RGBA`, `#RRGGBB` or `#RRGGBBAA`<br>`AA` is transparency; 00 [transparent] to FF [opaque]|
 | `back_width`               | **Description:** Controls the Backdrop Width for the Text Overlay. If `back_width` is not specified the Backdrop Sizes to the text<br>**Values:** Any Number greater then 0                                    |
 | `back_height`              | **Description:** Controls the Backdrop Height for the Text Overlay. If `back_height` is not specified the Backdrop Sizes to the text<br>**Values:** Any Number greater then 0                                  |
 | `back_align`               | **Description:** Controls the Alignment for the Text Overlay inside the backdrop. If `back_align` is not specified the Backdrop Centers the text.<br>**Values:** `left`, `right`, `center`, `top`, or `bottom` |
 | `back_padding`             | **Description:** Controls the Backdrop Padding for the Text Overlay.<br>**Values:** Any Number greater then 0                                                                                                  |
 | `back_radius`              | **Description:** Controls the Backdrop Radius for the Text Overlay.<br>**Values:** Any Number greater then 0                                                                                                   |
-| `back_line_color`          | **Description:** Controls the Backdrop Line Color for the Text Overlay.<br>**Values:** Color Hex Code in format `#RGB`, `#RGBA`, `#RRGGBB` or `#RRGGBBAA`                                                      |
+| `back_line_color`          | **Description:** Controls the Backdrop Line Color for the Text Overlay.<br>**Values:** Color Hex Code in format `#RGB`, `#RGBA`, `#RRGGBB` or `#RRGGBBAA``AA` is transparency; 00 [transparent] to FF [opaque]|
 | `back_line_width`          | **Description:** Controls the Backdrop Line Width for the Text Overlay.<br>**Values:** Any Number greater then 0                                                                                               |
 
 1. Each default overlay has a `key` that when calling to effect a specific collection you must replace `<<key>>` with when calling.