Perl regex match string including multiple newlines

How do I match a multiple line string in a file like

# custom prompt
aa=`command1 arg1 arg2`
bb=`command2 arg3 arg4`
PS1="$aa$bb"
# custom prompt

I am using this

perl -0pe 's/# custom prompt\n.*\n.*\n.*\n# custom prompt\n//gm' -i .bashrc

I want to delete all the lines between # custom prompt ~ # custom prompt (including the # custom prompt lines). But the one liner works only for 5 lines cases. Is there a way to match arbitrary multiple lines with new lines like (this does not work)

perl -0pe 's/# custom prompt[\n.]+# custom prompt\n//gm' -i .bashrc

>Solution :

Simply:

perl -i -0pe 's/# custom prompt.*# custom prompt//s' .bashrc

or with GNU awk:

awk -i inplace 'BEGIN{f=-1}/^# custom prompt/{f++;next}f' .bashrc