[求助]请帮忙把划线修改为指标线变色 (文华财经WH6赢顺V6.7)

参考：

RSV:=(CLOSE-LLV(LOW,N))/(HHV(HIGH,N)-LLV(LOW,N))*100;
K:SMA(RSV,P1,1);
D:SMA(K,P2,1);
PARTLINE(K>=50,K,COLORRED);
PARTLINE(K<=20,K,COLORGREEN);

 希望实现50―80区间显示一个颜色，80以上是红色，下面句子怎么调整才行，麻烦老师了

RSV:=(CLOSE-LLV(LOW,N))/(HHV(HIGH,N)-LLV(LOW,N))*100;
K:SMA(RSV,P1,1);
D:SMA(K,P2,1);
PARTLINE(K<80 AND K>=50,K,COLORBLUE);
PARTLINE(K>=80 ,K,,COLORRED);
PARTLINE(K<=20,K,COLORGREEN);

 参考：

RSV:=(CLOSE-LLV(LOW,9))/(HHV(HIGH,9)-LLV(LOW,9))*100;
K:SMA(RSV,3,1);
D:SMA(K,3,1);
IF(K<80 AND K>=50,K,NULL),COLORBLUE;
IF(K>=80,K,NULL),COLORRED;
IF(K<=20,K,NULL),COLORGREEN;