Expanded Usage section of README.md

README.md

@@ -9,7 +9,23 @@ The Tokyo Night color palette in CSS.
 
 ## Usage
 
-Copy the `colors.css` file either in whole or some parts of it into your projects. The colors are also available as filters which are useful for coloring SVGs.
+Copy the `colors.css` file to your project then start using the CSS variables:
+
+``` css
+.success {
+  color: var(--tn-dark-04);
+}
+```
+
+The colors are also available as filters which are useful for coloring black SVGs.
+
+``` css
+svg.icon {
+  filter: var(--tn-dark-filter-05);
+}
+```
+
+> **NOTE** The filters were generated with [Barrett Sonntag's CSS Filter Generator](https://codepen.io/sosuke/pen/Pjoqqp).
 
 ## Maintainer