The path to pandoc must be set as it's not sure that a path will exist.
I did this with a temporary PATH environment variable.

Beside I wrote some more comments for the code.

Signed-off-by: Conrad Zelck <git@simpel.cc>

Otherwise there would be a much greater gap between header and main.
Header normally is styled by icluded style via head.php. This has the
correct margin. The padding-top from this local style.css did two gaps
together.

Signed-off-by: Conrad Zelck <git@simpel.cc>

Signed-off-by: Conrad Zelck <git@simpel.cc>

A working website w/o file in- or output.

Signed-off-by: Conrad Zelck <git@simpel.cc>