"After Dark" (アフターダーク, Afutā Dāku^?) is a song by Japanese rock band Asian Kung-Fu Generation. It was released as the second single of their fifth studio album, World World World, on November 7, 2007, nearly a whole year after the release of the album's lead single. The single debuted in the top ten on the Oricon charts and was selected to be used as the seventh opening theme of the anime series Bleach.

The music video for "After Dark" was directed by Tadashi Tsukagoshi. The narrative video tells the surrealistic story of an ordinary young salaryman who wakes up one day to find wings sprouting out his back. At first, the man tries to hide them and continue going about his everyday life. However, as time goes on, the wings gradually grow larger and become increasingly harder to hide from his friends and co-workers. All the while, the scenes are intercut with a visual of AKG, expressing similar wings, playing the song in a giant birdcage.

While walking home one day, the man bears witness of a helpless window cleaner about to fall from a high-story building. The young man wishes to act, but hesitates due to the large crowd that has gathered around the scene. But when the cleaner begins to lose his grip, the young man throws off all hesitation, makes a dash towards him, spreads his wings, and soars to the rescue. At the same moment, the giant birdcage that had been holding AKG shatters to pieces. The video went on to win Best Rock Video at SPACE SHOWER Music Video Awards 08.

Color or colour (see spelling differences) is the visual perceptual property corresponding in humans to the categories called red, green, blue, and others. Color derives from the spectrum of light (distribution of light power versus wavelength) interacting in the eye with the spectral sensitivities of the light receptors. Color categories and physical specifications of color are also associated with objects, materials, light sources, etc., based on their physical properties such as light absorption, reflection, or emission spectra. By defining a color space, colors can be identified numerically by their coordinates.

Because perception of color stems from the varying spectral sensitivity of different types of cone cells in the retina to different parts of the spectrum, colors may be defined and quantified by the degree to which they stimulate these cells. These physical or physiological quantifications of color, however, do not fully explain the psychophysical perception of color appearance.