In simple words
A transit is where a planet is in the sky now, compared with your birth chart. Here, today's Sun makes a opposition (180°) to the spot where your Sun was when you were born.
It is a time of pressure that pushes you to grow, and it lasts two or three days. Your Today page tells you when it is happening for you.
Love
Relationships mirror you clearly now. Learn from the reflection.
Compromise is easier than usual if you lead with respect.
A partner may need you to step back a little.
Work
Results of earlier effort become visible.
Others' plans may compete with yours. Negotiate.
Review and refine rather than start fresh.
Mood
You may feel pulled outward. Protect some time for yourself.
Energy may dip. Rest is productive.
Balance self-care with care for others.
About the opposition
An opposition places two planets across the sky from each other. Each one pulls toward its own side of life. Oppositions are often felt through relationships, as if another person plays one side. The work is balance: holding both needs instead of swinging between them.