年少轻狂最情深年少不羁最倾心
[nián shăo qīng kuáng zuì qíng shēn nián shăo bù jī zuì qīng xīn]
This translates to 'In Youthful Recklessness, Deepest Emotions Flourish; In Youthful Restlessness, Hearts Become Most Devoted.' It conveys nostalgia for youthful passion and emotional intensity, contrasting innocence with strong feeling.