Help me write a word macro to highlight all the areas enclosed by two types of symbols.

Help me write a word macro to highlight all the areas enclosed by two types of symbols.

I am writing a word macro to highlight all the areas enclosed by two types of symbols. (Beginning: +++, End: ---)

The macro is used to automatically highly all the areas enclosed by a set of symbols. (Beginning: +++, End: ---)

Example document:

Not To be Highlighted_1
+++
Line To be Highlighted_1
Line To be Highlighted_2
Line To be Highlighted_3
Line To be Highlighted_4
Not To be Highlighted_2
+++
Line To be Highlighted_5
Line To be Highlighted_6
Line To be Highlighted_7
Line To be Highlighted_8
---

Once I execute the macro, I want the lines to be highlighted.

Thank you very much.