abstract backdrop background dark gloomy grunge grungy natural design nature texture winter color colour lavender lilac magenta pattern purple swirls violet altocumulus blue cloud clouds fleecy joy Nyberg sky summer white erode erosion rock rocks saavem stratification stratified stratum animal black fur skin stripes zebra architecture brick bricks building city classic red street wall brown ceramic close-up grain lines sand yellow botanical botany bromeliad fern green leaf leaves plant vein