From 81344da09a8abb044860056476e21827045e60e8 Mon Sep 17 00:00:00 2001
From: "russell@unturf.com" <russell@unturf.com>
Date: Sun, 26 Apr 2026 15:55:55 -0400
Subject: [PATCH] fix: PDF body fills page width (override pandoc CSS
 max-width)
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Pandoc's --standalone HTML5 template applies max-width: 36em + margin: 0
auto + padding: 50px to body, centering content in a narrow column on
any page size. With wkhtmltopdf at 15mm page margins, effective content
margins were measuring ~55mm because pandoc's CSS added ~40mm of inner
padding on top.

Inject a header-includes <style> block that strips body's max-width,
margin, and padding so content fills the page minus wkhtmltopdf's own
page margins. Measured: 55mm → 15mm left margin.
---
 remarkbox/lib/pandoc.py | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/remarkbox/lib/pandoc.py b/remarkbox/lib/pandoc.py
index 0cb94cc..82d09c5 100644
--- a/remarkbox/lib/pandoc.py
+++ b/remarkbox/lib/pandoc.py
@@ -220,6 +220,11 @@ def convert(source, from_format="markdown", to_format="html5", title=None, stand
     # wkhtmltopdf defaults to ~25mm top which leaves a half-page of empty
     # space above content. 12mm/15mm is enough to look printed without
     # wasting paper.
+    #
+    # Pandoc's --standalone HTML5 template applies `max-width: 36em` and
+    # `padding: 50px` to body, centering content in a narrow column on
+    # any size paper. We want content to fill the page (minus wkhtmltopdf
+    # margins) so we override that CSS via header-includes.
     if to_format == "pdf":
         cmd.extend([
             "--pdf-engine=wkhtmltopdf",
@@ -227,6 +232,7 @@ def convert(source, from_format="markdown", to_format="html5", title=None, stand
             "-V", "margin-bottom=12mm",
             "-V", "margin-left=15mm",
             "-V", "margin-right=15mm",
+            "-V", "header-includes=<style>html,body{max-width:none!important;padding:0!important;margin:0!important;}</style>",
         ])
 
     if is_binary: