How do I enable syntax highlighting for Fortran in GitBook - syntax-highlighting

Question

Original Question:
I can't find how to activate syntax highlighting on GitBook!
It works perfectly when I look at the .md files on GitHub where my repository is hosted, by not when I look at my rendered gitbook on the web.
Any ideas? Thanks
Edit:
it works for bash, Python, C, C++, javascript, etc, but not for Fortran! It seems that gitbook and github don't use the same syntax highlighting package.
Is there a way to activate syntax highlighting with Fortran on GitBook?
Sample code:
``` fortran
program compute_t
implicit none
integer :: d1, d2, d3, d4 d5 ! Input data
integer :: u1, u2, v, w, t ! Computed entities
call read_data(d1,d2,d3,d4,d5)
call compute_u(d1,d2,u1)
call compute_u(d3,d4,u2)
call compute_w(d5,w)
call compute_v(u2,w,v)
call compute_t(u1,v,t)
write(*,*), "t=", t
end program
```

Answer 1

GitBook's own documentation, which is available as a GitBook, uses named fenced code blocks as popularized by GitHub:
```markdown
# H1
## H2
### H3
#### H4
##### H5
###### H6
```
Although I can't find any documentation that explicitly says this is supported, I suspect that it works just fine.
Edit:
it works for bash, Python, C, C++, javascript, etc, but not for Fortran! It seems that gitbook and github don't use the same syntax highlighting package.
GitHub uses a Ruby library called Linguist for syntax highlighting. It looks like GitBook uses the JavaScript library highlight.js, which doesn't support Fortran.
Is there a way to activate syntax highlighting with Fortran on GitBook?
Short of contributing Fortran support to highlight.js, I don't think there's a good solution for this at the moment.