CSS to create "channel off air" background:
background: linear-gradient(to right,
silver calc(14.28% * 1),
yellow calc(14.28% * 1 + .01%),
yellow calc(14.28% * 2),
aqua calc(14.28% * 2 + .01%),
aqua calc(14.28% * 3),
chartreuse calc(14.28% * 3 + .01%),
chartreuse calc(14.28% * 4),
fuchsia calc(14.28% * 4 + .01%),
fuchsia calc(14.28% * 5),
red calc(14.28% * 5 + .01%),
red calc(14.28% * 6),
blue calc(14.28% * 6 + .01%),
blue calc(14.28% * 7)
)