NR:LDAY,LINETHICK;
JD:=CROSS(NR,15);
JS:=COUNT(JD,0);
YS:=MOD(JS,4);
VERTLINE(JD AND YS=0),COLORFF00;
VERTLINE(JD AND YS=1),COLORFF;
VERTLINE(JD AND YS=2),COLORFFFF;
VERTLINE(JD AND YS=3),COLORFFFFFF;