docs(range): add range pin CSS custom properties (ionic-team#19537)

Author: nickstucko

core/api.txt

@@ -881,6 +881,8 @@ ion-range,css-prop,--knob-background
 ion-range,css-prop,--knob-border-radius
 ion-range,css-prop,--knob-box-shadow
 ion-range,css-prop,--knob-size
+ion-range,css-prop,--pin-background
+ion-range,css-prop,--pin-color
 
 ion-refresher,none
 ion-refresher,prop,closeDuration,string,'280ms',false,false

core/src/components/range/range.scss

@@ -14,6 +14,8 @@
    * @prop --knob-border-radius: Border radius of the range knob
    * @prop --knob-box-shadow: Box shadow of the range knob
    * @prop --knob-size: Size of the range knob
+   * @prop --pin-background: Background of the range pin
+   * @prop --pin-color: Color of the range pin
    */
   --knob-handle-size: calc(var(--knob-size) * 2);
 

core/src/components/range/readme.md

@@ -233,6 +233,8 @@ export default {
 | `--knob-border-radius`    | Border radius of the range knob    |
 | `--knob-box-shadow`       | Box shadow of the range knob       |
 | `--knob-size`             | Size of the range knob             |
+| `--pin-background`        | Background of the range pin        |
+| `--pin-color`             | Color of the range pin             |
 
 
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