Fix typo on docs

docs/index.html

@@ -888,7 +888,7 @@
 /* This changes all the animations globaly */
 :root {
   --animate-duration: 800ms;
-  --animation-delay: 0.9s;
+  --animate-delay: 0.9s;
 }
 </code></pre>
 <p>Custom properties also make it easy to change all your animations time-constrained properties on the fly. It means that you can have a slow-motion or time-lapse effect with a javascript one-liner:</p>

docsSource/sections/01-usage.md

@@ -70,7 +70,7 @@ Example:
 /* This changes all the animations globaly */
 :root {
   --animate-duration: 800ms;
-  --animation-delay: 0.9s;
+  --animate-delay: 0.9s;
 }
 ```