Making text larger without changing size of superscript?

Question

I have the following plot:

    test1 = Plot[1000*Exp[-0.03*t], {t, 0, 1000}, 
  FrameLabel -> {None, 
    Style[Row[{Subsuperscript["N", "W", "Post"]}], FontSize -> 30, 
     Black]}, Frame -> True]

I am trying to change the frame label such that the letter "N" is sufficiently larger than its corresponding Subsuperscript. Is there any easy way to do this?

Answer 1

You can style each element of the Subsuperscript independently:

Subsuperscript[
  Style[a, FontSize -> 20, FontColor -> Blue], 
  Style[b, FontSize -> 10, FontColor -> Red], 
  Style[c, FontSize -> 12, FontColor -> Gray]]

Edit to clarify usage as FrameLabel

Plot[1000*Exp[-0.03*t], {t, 0, 1000}, 
  FrameLabel -> {None, 
                 Subsuperscript[
                   Style["N", FontSize -> 35, FontColor -> Red, FontFamily -> "Alegreya SC"], 
                   Style["W", FontSize -> 10], 
                   Style["Post", FontSize -> 14, FontSlant -> Italic]]}, 
  Frame -> True]