appearance beams breaking-through bright cloud clouds color colour concepts contrast contrasting dark darkening dramatic dusk glory light lighting natural nature radiant radiating rays shining shining-through signs skies sky spreading sun sunlight abstract background colours desktop fiction Fractal future futuristic lightin other science texture wall wallpaper walls write art back balloon circles colors curls graphics grunge lights pop rainbow ripples stars vector agriculture blue field grass grassy green heaven hills horizon landscape october scenery valley