one row has 2 states:
(1) the whole row is highlighted
(2) only the arrow is highlighted
but the problem is with the second point：when we want to highlight arrow，the whole row is still highlighted
我的任务
Figure out a way to handle both scenarios
boundary conditions & guidance
- it doesn’t mean that while highlighting the arrow, we cannot highlight the whole row as well…
- it means that currently it looks bad
- and it needs to be more visble