Apply a style if the value of a cell appears in another range

[milo789456654897]

Hello,
I would like to set a conditional in column 1 that applies a style if the cell’s value can be found in another range (column 2).
In my example, there’s a match for 1 and 6.

[PKG]

Unbenannt 1.ods (40,1 KB)

[milo789456654897]

Hello,
Thank you for trying but it doesn’t work for me, nothing happens.

[sokol92]

@milo789456654897

Thank you for trying but it doesn’t work for me, nothing happens.

Please upload your file.

[milo789456654897]

I am stupid,
In the image, I used “,” instead of “;”.
PKG answered my question. Thank you to both.
For future reference : COUNTIF(column 2 range ; start of column 1)