Cannot set correct size for variable pitch font in Doom Emacs

Question

I am trying to use a variable-pitch font for Org-mode:

(add-hook! 'org-mode-hook #'mixed-pitch-mode)

I am specifying a variable pitch font that is normally renders much smaller than the fixed pitch one:

(setq doom-font (font-spec :family "Fira Code" :style "Retina" :size 14)
      doom-variable-pitch-font (font-spec :family "ETBembo")
      doom-big-font (font-spec :family "Fira Code" :style "Retina" :size 24))

However, no matter what I do I cannot change the size of the default text face in Org mode. I can change size for title, org-levels, etc. but not the default text font. I've tried this:

(setq doom-font (font-spec :family "Fira Code" :style "Retina" :size 14)
      doom-variable-pitch-font (font-spec :family "ETBembo" :height 1.3)
      doom-big-font (font-spec :family "Fira Code" :style "Retina" :size 24))

and this:

(setq doom-font (font-spec :family "Fira Code" :style "Retina" :size 14)
      doom-variable-pitch-font (font-spec :family "ETBembo" :size 18)
      doom-big-font (font-spec :family "Fira Code" :style "Retina" :size 24))

and even this:

(after! org (custom-set-faces! '(org-default :weight normal :slant normal :height 2.9)))

and it still fails. Can somebody help me?

screenshot:

Answer 1

I found the answer. Doing this does the trick:

(use-package! mixed-pitch
  :hook (org-mode . mixed-pitch-mode)
  :config
  (setq mixed-pitch-set-heigth t)
  (set-face-attribute 'variable-pitch nil :height 1.3))

I have set the height for my normal font to 1.0:

(setq doom-font (font-spec :family "Fira Code" :style "Retina" :size 14 :height 1.0)
      doom-variable-pitch-font (font-spec :family "ETBembo" :style "RomanOSF" :height 1.3)
      doom-big-font (font-spec :family "Fira Code" :style "Retina" :size 24))

Reference: I found this from this link.