How to align a to the middle (horizontally/width) of the page [duplicate]

Answer 1

Some other pre-existing setups from older code that will prevent div page centering L&R are:

1. Other classes hidden in external stylesheet links.
2. Other classes embedded in something like an img (like for older external CSS print format controls).
3. Legend code with IDs and/or CLASSES will conflict with a named div class.