class MegaAPIError(Exception):
    """Base exception for all MegaMarket API errors."""
    pass

class MegaAuthError(MegaAPIError):
    """Raised when authentication fails (HTTP 401 or 403)."""
    pass

class MegaRateLimitError(MegaAPIError):
    """Raised when API rate limits are exceeded (HTTP 429)."""
    pass

class MegaBadRequestError(MegaAPIError):
    """Raised when API returns HTTP 400 (Bad Request)."""
    pass

class MegaNotFoundError(MegaAPIError):
    """Raised when API returns HTTP 404 (Not Found)."""
    pass