Ah, well the variable you have defined in your controller is _bar1Color but your template is expecting bar1Color.
So you’ll need to make them match. I’d suggest the latter styling, as normally variables that start with an underscore are meant to convey that they’re private/internal use only.
If you can find my post earlier… You’ll see that this will not work in Safari. You will need to set the class and not the style. Style is read only you’ll need to use [(ngClass)]=“bar1color” or something along those lines.