Nested IF Sums

Hi there, can some one please help with this nested if sum,

As per the attached i want a formula that returns

if B2 is = to or > than C2 = "In stock", if B2 is < C2 but > than 0 = "Part Stock" but if B2 is less than 0 = "Out of stock"

I think this will be a nested if sum but i cant get it to work

Thanks