Time

Before Einstein it was assumed that all events that are observed to happen at a certain time, now, happened simultaneously, or at the same time, for all observers. Time was absolute.
So in the animation, if we ask the observers at blue, grey, and yellow to tell us when the two lights are turned on, they would all say, now, and they would all assume that they are talking about the same now moment.
However, as shown, due to the time it takes light to travel a given distance, each observer sees the lights being turned on at a different now moment.

So to us, the fourth removed observer, if we started a clock at our location, as shown by the blue, grey, and yellow lines; we would see that the yellow observer sees both lights at the same time. The blue observer sees the red light first and the green light second. The grey observer sees the green light first and the red light second.

Yellow = Red and Green simultaneous
Blue = Red first then Green second
Grey = Green first then Red second

So when asked,
Yellow would insist that both events happened at the same time, now.
Blue would insist that the Red light was turned on first, now, then the Green light.
Grey would say that the Green light was turned on, now, then the Red.
We, the fourth observer, can see that they are all correct.

The order of the occurrence of the two lights, and what happens now, has been reversed for the Blue and Grey observers. In this example the observers are stationary and the reversal is based on the time that light needs to travel a set distance. But the principle is the same if we set one or all of the observers in motion.

So now, or time, is relative, and is different for each observer.

 

Thinking this over some more...

If we pick a certain point in our timeline, as the fourth observer, and label it now,

We could say that:
Right now, Red and Green have occurred in Yellow's past,
Red is now occurring in Blue's present and Green is in Blue's future.
Green is now occurring in Grey's present and Red is in Grey's future.

And we have past, present, and future all existing at the same now moment, for the same Red and Green events, depending on your point of reference.

 

If everyone starts their stopwatch at the same moment, they will still observe the occurrence of the red and green lights at different times in relation to each other. This is what happens in the example. The fourth observer is, in effect, the stopwatch.

This is not to say that causality can be reversed. Once the observation is made by each observer, they can not reverse it.

 

But Neon, in a local environment all observers are essentially sharing the same time in relation to each other. There must be a huge difference of time or distance for the relative nature of time to be seen.

 

I think it says that space/time is dependent on the observer and is not absolute.
The observer is an active part of the universe.