Final answer:
The detail that best supports the theme that people should enjoy the good times in life is the line, 'While we are in the mood of joy. Let us celebrate!'
Step-by-step explanation:
The detail that best supports the theme that people should enjoy the good times in life is the line, 'While we are in the mood of joy. Let us celebrate!' This line encourages people to embrace and celebrate the moments of joy in life. It suggests that these happy times are fleeting and should not be wasted.