936d93d8d9c82bc0f22ca4ded6f764d2bd918f4b6c6ec1c4ccfd1cb6dd5334c3

```python
def fibonacci(n):
    """
    Calculates the nth Fibonacci number recursively.
    Assumes n is a non-negative integer.
    """
    if n <= 0:
        return 0
    elif n == 1:
        return 1
    else:
        # Recursive step: F(n) = F(n-1) + F(n-2)
        return fibonacci(n - 1) + fibonacci(n - 2)

# Example usage:
number = 8
result = fibonacci(number)
print(f"The {number}th Fibonacci number is: {result}")  # Output: The 8th Fibonacci number is: 21
```