minor fixes

Author: iliakan

7-animation/2-css-animations/article.md

@@ -303,7 +303,7 @@ The alternative value `end` would mean that the change should be applied not in
 
 So the process for `steps(9, end)` would go like this:
 
-- `0s` -- `0`
+- `0s` -- `0` (during the first second nothing changes)
 - `1s` -- `-10%` (first change at the end of the 1st second)
 - `2s` -- `-20%`
 - ...