They symbolize or they are like an identity of a married woman. Like flowers increase beauty of a garden same as them bangles adorn a women. In Hindu mythology it is seen as a symbol for the existence of their husband.
So people the gift given by Virat to Sai is the significance that Sai is adding colours to Virat's by being in his life. Those different colours were of red colour for love, even for their fights, pink colour for her beauty, yellow colour for sunshine, blue colour for health and serenity...
COLOURFUL SAIRAT LOVE
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