Prevent and add consistency in typographie with `font-size-ajust: from-font;`

[czerkies]

• [x] https://drafts.csswg.org/css-fonts-5/#font-size-adjust-prop
• [x] #139

[czerkies]

x-height match from main font:

font-size-adjust: from-font;

x-height adjusted from main font

font-size-adjust: ex-height 0.47;

[czerkies]

• [x] Set main font property on html element with 100% as value.
• [x] Set font-size: var(--fnt-sz-prmr); on body element
• [x] Use font-size-adjust: from-font; value to match the main front.