Color-based antonym of "blues"?

Solution 1:

Will peachy do?

Peachy (adj):

1. Resembling a peach, especially in color or texture.
2. [Informal] Splendid; fine.

[American Heritage Dictionary]

Solution 2:

The colour pink is associated with health and happiness:

From Farlex

in the pink
Healthy; in good condition.

and Farlex also has

tickled pink
Very pleased with someone or something.

So perhaps

Sridhar is tickled pink; he sees no reason not to enjoy this moment, regardless of the situation he is in.

Solution 3:

Credit goes to Jens Petersen on Twitter

Melancholy is dark blue, the opposite temperament is Sanguine: yellow

EDIT: Even though Jens described sanguine as "yellow", the dictionary definition below says it is "blood-red" (see comments for further context).