Wedding anniversaries are usually not a time to entertain friends, and are more private. However, as a subordinate, sending a gift to express your blessing will indeed deepen the leader's favor towards you. You can order a bouquet of flowers, fill out a greeting card, and have the clerk of the flower shop deliver it to the leader's home on the day of the festival. Flowers are both romantic and high school. Such a gift will make you look more thoughtful, and the leader's wife will definitely be very happy, and your purpose will be achieved. Or you can send a handicraft, preferably an auspicious gift with exquisite appearance and a happy and satisfactory meaning. You don't need to spend too much money, just a thought is enough. You can chat with the leader more, find out what he likes, and choose a gift that suits his taste.
In short, this kind of festival is spent by the leader and his family. As an outsider, you won't be too particular. A small gift to express your blessing will achieve the purpose. Everyone is willing to get more care from others, a caring blessing from subordinates, and your leader will definitely look at you with new eyes.