You have so many blunders
1.Two mentioned above.
2.Target class without dot .
3.Use ; after each span child selector.
4.it's not font style bolder it will be font weight bolder .
5.in rgba a works between 0 and 1 .
6. No need to use translate if you have position absolute .use absolute to put at desired place.
7.no need to link css page here in sololearn playground it's already linked.
You realy need to revise css lessons.