4 day old seedling color question

Hi!! I woke up this morning and my little one had really grown. But I do notice the middle of her is very light greenish/yellow. Is this normal? Is this just part of new growth?

PH: 6.5
TEMP: 77
HUMIDITY: 40
LIGHTS: (2) 42w CLF's 2" away
MEDIUM: FF Happy Frog/Roots Organics/Perlite
WATERING: When pot is feather light, no misting
NUTES: None

Thank you!

yes, it is normal, she's fine

Thank you