Also i think it's harder to learn if the lesson doesn't say what number is it.
I was seeing the number characters of eight, three, one and seven, but i only knew it till the end, making it harder to learn. Also, the lesson is showing characters that has nothing to do with lesson (or it seems to be) such as Lìng and others. Just a suggestion.
Yes, if you hover over the character, you'll see the meaning... but only in the very last exercises of the lesson. During most of the lesson you are just learning characters and their pronunciation, not knowing what they mean until the very end. This makes it rather hard to learn them.
It would be good to have the meanings at the very beginning of the lesson.