Use "Yu Gothic Medium" in Windows sans-serif display

Author: peaceroad

css/src/ReadiumCSS-ebpaj_fonts_patch.css

@@ -47,7 +47,7 @@
        local("ヒラギノ角ゴ W3"), /* for old  Safari */
        local("HiraginoKaku-W3-90msp-RKSJ-H"), /* ヒラギノ角ゴ W3(TrueType) */
        local("YuGothic-Medium"), local("YuGothic"), /* 游ゴシック体(macOS) */
-       local("Yu Gothic"), /* 游ゴシック(Windows) */
+       local("Yu Gothic Medium"), local("Yu Gothic"), /* 游ゴシック(Windows) "Yu Gothic" is a fallback. */
        local("BIZ UDPGothic"); /* BIZ UDPゴシック */
 }
 
@@ -74,6 +74,6 @@
        local("ヒラギノ角ゴ W3"), /* for old Safari */
        local("HiraKakuDS-W3-83pv-RKSJ-H"), /* ヒラギノ角ゴ W3(TrueType) */
        local("YuGothic-Medium"), local("YuGothic"), /* 游ゴシック体(macOS) */
-       local("Yu Gothic"), /* 游ゴシック(Windows) */
+       local("Yu Gothic Medium"), local("Yu Gothic"), /* 游ゴシック(Windows)  "Yu Gothic" is a fallback. */
        local("BIZ UDGothic"); /* BIZ UDゴシック */
 }

css/src/modules/ReadiumCSS-base.css

@@ -123,11 +123,11 @@ math {
   --RS__lineHeightCompensation: 1.167;
 
   /* Extra variables for Japanese font-stacks as we may want to reuse them for user settings + default */
-  /* BIZ UD fonts will work on Windows. If you set half-width (ASCII) characters to `upright` using `text-orientation`, the width of these characters remains narrow. In this case, specify `font-variant-east-asian: full-width;` as well. */
+  /* This setting uses the BIZ UD font for serif and the Yu font for sans serif on Windows. Note: When using the BIZ UD font for vertical writing display, if you set half-width (ASCII) characters to stand upright with `text-orientation: upright`, the width of these characters is narrow. By specifying `font-variant-east-asian: full-width;` at the same time, you can display the characters with the width of one full-width character. */
   --RS__serif-ja: "Hiragino Mincho ProN", "Hiragino Mincho Pro", "YuMincho", "BIZ UDPMincho", "Yu Mincho", "ＭＳ Ｐ明朝", "MS PMincho", serif;
-  --RS__sans-serif-ja: "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Hiragino Kaku Gothic Pro", "ヒラギノ角ゴ W3", "YuGothic", "BIZ UDPGothic", "Yu Gothic", "ＭＳ Ｐゴシック", "MS PGothic", sans-serif;
+  --RS__sans-serif-ja: "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Hiragino Kaku Gothic Pro", "ヒラギノ角ゴ W3", "YuGothic", "Yu Gothic Medium", "BIZ UDPGothic", "Yu Gothic", "ＭＳ Ｐゴシック", "MS PGothic", sans-serif;
   --RS__serif-ja-v: "Hiragino Mincho ProN", "Hiragino Mincho Pro", "YuMincho", "BIZ UDMincho", "Yu Mincho", "ＭＳ明朝", "MS Mincho", serif;
-  --RS__sans-serif-ja-v: "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Hiragino Kaku Gothic Pro", "ヒラギノ角ゴ W3", "YuGothic", "BIZ UDGothic", "Yu Gothic", "ＭＳゴシック", "MS Gothic", sans-serif;
+  --RS__sans-serif-ja-v: "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Hiragino Kaku Gothic Pro", "ヒラギノ角ゴ W3", "YuGothic", "Yu Gothic Medium", "BIZ UDGothic", "Yu Gothic", "ＭＳゴシック", "MS Gothic", sans-serif;
 }
 
 :lang(km) {