What do green, blue, and yellow roads mean in Japan?

Question

I read this answer by Sed Chapman on Quora about "Why are roads in Japan painted red?"

It isn’t just red, but green, blue, yellow, and other colors can be found. Most often these colors are found at intersections or areas where roads merge. They do it to provide some contrast to the scene in order to alert the driver that something is different and that they should pay attention.

I've never seen any green or yellow roads in Japan. I might have seen blue roads designated for bicycling. So I'm dubious about that unsupported Quora answer.

What do green, blue, yellow roads mean in Japan? Does it mean a vague "pay attention", as the quote below claims, or do they have a clearer meaning? I'd be surprised if Japan uses 4 colors for the same meaning.

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Example of a red road in Japan:

Answer 1

There are no rules governing the color codes, so while the use is arbitrary, there is a pattern to this.

• Red: Usually used in areas that may be more prone to accidents and require attention. Intersections w/o signals, sudden curves, lanes where buses makes stops... Some places use it to indicated no-parking zones. They also provide extra grip, according to some sites.

• Green: Usually used to indicate school zones. A lot of times, just the outside is painted green to indicate areas dedicated for pedestrians on roads that don't have dedicated sidewalks (link).

• Blue: Blue is often used to indicate bicycle lanes, but can also be used to indicated specific lanes like a right turn lane. You'll see blue lines or dotted lines as well.

I've never seen roads that are yellow and I can't fine any information on yellow roads, so I don't believe these exists in Japan. And I've never seen red like the color of your pic! Maybe that's how the red looks like when it's freshly painted...

I found a lot of the information I listed here.