Update style_guide.rst

Author: echedey-ls

docs/sphinx/source/contributing/style_guide.rst

@@ -76,9 +76,11 @@ Parameter names and units
 -------------------------
 
 When specifying parameters and their units, please follow these guidelines:
+
 - Use the recommended parameter name and units by :ref:`variables_style_rules` where possible.
 - Enclose units in square brackets, e.g. ``[W]``.
 - Use unicode superscripts symbols for exponents, e.g. ``m²``.
+
   These superscripts characters are ``⁰``, ``¹``, ``²``, ``³``, ``⁴``, ``⁵``, ``⁶``, ``⁷``, ``⁸``, ``⁹``, ``⁺``, ``⁻``. Degree symbol is ``°``.
 
 - Link to a brief description of the magnitude in the :ref:`variables_style_rules` section if it exists, via the sphinx role ``:term:`glossary_term```. For example, to document ``dni`` use: