From 8e2c60e76e47b4c48e407504b4b2984a3f1e9d21 Mon Sep 17 00:00:00 2001
From: Alex Cabal <alex@standardebooks.org>
Date: Mon, 28 Dec 2020 20:05:45 -0600
Subject: [PATCH] Update core.css to new standards

---
 src/epub/css/core.css | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/epub/css/core.css b/src/epub/css/core.css
index 221bce3..0764884 100644
--- a/src/epub/css/core.css
+++ b/src/epub/css/core.css
@@ -122,7 +122,8 @@ section[epub|type~="endnotes"] > ol > li{
 	margin: 1em 0;
 }
 
-@media (prefers-color-scheme: dark){
+/* Invert images in dark mode. RMSDK requires a target media as well as a state. */
+@media all and (prefers-color-scheme: dark){
 	img[epub|type~="se:image.color-depth.black-on-transparent"]{
 		filter: invert(100%);
 	}