How can I color the increasing and decreasing slopes on a line chart?

I'm creating a line chart in Google Spreadsheets. How can I display the increasing and decreasing sections in different colors?

I am attempting to do this by creating auxiliary columns with formulas and overlaying them onto the original chart (here, column B contains the data to be displayed and the formulas are set as if they were in cells C2 and D2):

=if(($B2>$B3)+($B2<$B1), $B2, na())
=if(($B2<=$B3)*($B3>$B4)+($B1<=$B2)*($B2>$B3), $B2, na())

This is the current result with incorrectly colored sections 12-13, 23-24, and 28-29 (the issue arises with zigzag sections like [1, 2, 1, 2, 1, 2], where increasing and decreasing alternate at every step):

I wonder if it's possible to write a formula that separates different trends into individual columns or inserts an additional empty half-step between adjacent trends.

Experimentation Document

The data I'm working with:

• The first 2 columns are your data and the last 3 columns are the final result needed to form the chart. The rest are intermediate steps(which can be collapsed).

• We split the data into two sets of data points per row. Each data point will repeat twice. This is done to calculate the difference. In C2,

  =WRAPROWS( REDUCE(B2,B3:B32,LAMBDA(a,c,IF(COUNT(a)=1,{a;c},{a;INDEX(a,COUNTA(a));c}))),2)
  

• We calculate the consecutive difference in E2:

  =ARRAYFORMULA(C2:C31-D2:D31)
  

• Then we split the data points again to calculate sets of increases or decreases in F1:

  =REDUCE(
    {"Increase", "Decrease";"",""},
      E2:E31,
      LAMBDA(a,c,
        LET(
          r,TOCOL(OFFSET(c,0,-2,1,2)),
          e,VSTACK("",""), 
          VSTACK(a,IF(c<0,HSTACK(r,e),HSTACK(e,r))))))
  

• We add the Step back as doubled sequential numbers in H1:

  =REDUCE("Step",A2:A36,LAMBDA(a,c,VSTACK(a,c,c)))
  

Using X axis as Column H and Series as Column F and G, we can get the desired result.