轻松 is one of the most common positive adjectives in daily life. 轻松一下 means 'take it easy / relax a bit'. It can describe a feeling (心情很轻松), an activity (轻松的工作), or how something was done (轻松地完成).
mistakes
The traditional character is 輕鬆 (with 鬆, 'loose/fluffy'). Don't confuse simplified 松 (which covers both 'pine tree' and 'loose') - in this word it means 'loose/relaxed'.
