feat(api): rename API for distance custom property

Author: Simon Finney

README.md

@@ -33,7 +33,7 @@ import 'custom-properties-parallax';
 
   | Name             | Type   | Default  |
   | ---------------- | ------ | -------- |
-  | `--cpp-modifier` | Unit   | 0.625rem |
+  | `--cpp-distance` | Unit   | 0.625rem |
   | `--cpp-speed`    | Number | 0.5      |
 
 * For individual control, leverage the cascade by declaring any of the above custom properties within the CSS selectors of the target elements. For example:

src/parallax/constants.js

@@ -4,14 +4,14 @@
  */
 
 const DEFAULT_VALUES = {
-  MODIFIER: '.0625rem',
+  DISTANCE: '.0625rem',
   SPEED: 0.5,
 };
 
 const NAMESPACE = 'cpp';
 
 const CUSTOM_PROPERTIES = {
-  MODIFIER: `--${NAMESPACE}-modifier`,
+  DISTANCE: `--${NAMESPACE}-distance`,
   PARALLAX: `--${NAMESPACE}-parallax`,
   SPEED: `--${NAMESPACE}-speed`,
 };

src/parallax/index.js

@@ -32,7 +32,7 @@ function create(parallaxElement) {
   parallaxElement.style.setProperty(
     'transform',
     `translate3d(0, calc(var(${CUSTOM_PROPERTIES.PARALLAX}) * var(${
-      CUSTOM_PROPERTIES.MODIFIER
+      CUSTOM_PROPERTIES.DISTANCE
     })), 0)`
   );