Dinomagic: Magic you can see

Guess what is 'Dinomagic' and
stand to win 1kg of me if you get
the correct answer.

I may look white but
I am green at heart.

I save you time and space
by working smart.

I am your granny's best-kept secret,
your baby's best friend.

Let's fight the nasties,
hand in hand.

I am all you need now
until the end...

What am I?