custom BB code not run

[TongGiang]

I create a BB code for my board V 3.6.7 but when i used in my post, it not run pls help me to solve.
My BBcode :
Tag : shadow
Replacement : <shadow>{param}</shadow>
Example: |shadow||/shadow|

[EnIgMa1234]

Make the replacement this:
<font style="filter:Shadow(color={option},strength=4);">{param}</font>

And example to:
Shadow