OptionalcolorSymbol color; 'auto' (default): black on light marks, white on dark ones
OptionalopacitySymbol opacity 0..1 (times the color alpha and the mark alpha; default 0.45)
OptionalrotationPattern rotation in degrees, clockwise on screen (SVG rotate)
OptionalspacingTile size in CSS px: distance between symbol centers (1..1024)
OptionalsymbolSymbol tiled over the mark ('line': stripes, symbolSize thick)
OptionalsymbolSymbol size in CSS px (0 < size <= 512)
Pattern of one series / item; missing fields come from the automatic pattern.