precipitation , water
Perhaps something relating to it is inside, but it is unlikely that the Rainbow Kindgom itself is in there unless the box is much bigger on the inside that it is on the outside.
The order of colors in a secondary rainbow is reversed compared to a primary rainbow, so the inside curve would have a slightly broader band of red at the top and blue at the bottom.
inside the rainbow
Inside a house in Viridian City
The color on the inside of a single rainbow's arc, in the generally defined seven-color spectrum, is violet. The order of colors in a rainbow, from the outside to the inside, is red, orange, yellow, green, blue, indigo, and violet. Therefore, violet is the innermost color.
The sky inside a rainbow appears brighter because raindrops refract and reflect sunlight, making the sky outside the bow relatively darker. This creates a contrast in brightness and color perception that makes the sky inside the rainbow seem brighter.
Highly educated research scientists refer to that rare phenomenon as a "double rainbow".
Funfetti!
A double rainbow appears in the sky when sunlight is reflected twice inside raindrops, creating a secondary rainbow above the primary one.
A rainbow is formed when sunlight is refracted, or bent, and reflected inside raindrops, creating a spectrum of colors in the sky.
A secondary rainbow is dimmer than a primary rainbow because it is caused by a double reflection of sunlight inside raindrops, which results in less light being reflected back to the observer.
Get them to Lv.40!