The actual law is the best link I have, and that section isn't overly complicated to read.

• For 2021.
• Refundable.
• Can use $8,000 of expenses for 1 kid or $16,000 of expense for 2 or more kids.
• 50% credit for AGI up to $125,000.
• AGI of $125,000 to $185,000 it phases down to 20%.
• AGI $400,000 to $440,000 it phases down to 0%.

https://www.congress.gov/117/bills/hr1319/BILLS-117hr1319enr.pdf#page=156