You can use unicode characters here for sub- and super-script characters.

[Make7]

99⁰
99¹
99²
99³
99⁴
99⁵
99⁶
99⁷
99⁸
99⁹

99₀
99₁
99₂
99₃
99₄
99₅
99₆
99₇
99₈
99₉

They are kinda small and inconsistent, but for some math and chemistry they're better than nothing. My biggest concern with using them is I am not certain they will display correctly in all the browser / OS combinations that people might be using.

c² = a² + b² ? 2ab cos 𝛾

C₁₂H₂₂O₁₁

https://en.m.wikipedia.org/wiki/Unicode_subscripts_and_superscripts