Doing cardio after leg day won't kill your gains. In fact, certain types of cardio may actually help rather than hurt muscle growth.
Cardio on Lifting Days or Different Days? - The Muscle PhD
Does Cardio Count As A Leg Workout? (Yes, Here's How) – Fitbod
Can You Workout Legs 2 Days In A Row? (Pros & Cons
Two-A-Day Workouts Explained: Better Results Without Overtraining
Level Up Your Leg Day Warm Up Exercises
Why you shouldn't skip leg day
Running After Leg Day: The Benefits + Drawbacks
Can You Work Out the Same Muscle Two Days in a Row?
20 Best Leg Workouts For Women: Home & Gym – SWEAT