diff --git a/css/src/ReadiumCSS-ebpaj_fonts_patch.css b/css/src/ReadiumCSS-ebpaj_fonts_patch.css
index 012a542..ee7623c 100644
--- a/css/src/ReadiumCSS-ebpaj_fonts_patch.css
+++ b/css/src/ReadiumCSS-ebpaj_fonts_patch.css
@@ -19,62 +19,61 @@
      <meta property="ebpaj:guide-version">1.1</meta>
 */
 
+/* 
+   Hiragino PostScript Font name lists:
+   https://www.screen.co.jp/ga_product/sento/support/QA/ss_psname.html
+*/
+
 /* 横組み用 (horizontal writing) */
 
 @font-face {
   font-family: "serif-ja";
-  src: local("ＭＳ Ｐ明朝"),
-       local("MS PMincho"),
-       local("Hiragino Mincho Pro"),
-       local("ヒラギノ明朝 Pro W3"),
-       local("游明朝"),
-       local("YuMincho"),
-       local("ＭＳ 明朝"),
-       local("MS Mincho"),
-       local("Hiragino Mincho ProN");
+  src: local("ＭＳ Ｐ明朝"), /* for IE */
+      local("MS PMincho"), /* ＭＳ Ｐ明朝 */
+      local("HiraMinProN-W3"), local("Hiragino Mincho ProN"), /* ヒラギノ明朝 ProN W3 */
+      local("HiraMinPro-W3"), local("Hiragino Mincho Pro"), /* ヒラギノ明朝 Pro W3 */
+      local("YuMin-Medium"), local("YuMincho"), /* 游明朝体(macOS) */
+      local("Yu Mincho"), /* 游明朝(Windows) */
+      local("BIZ UDPMincho"); /* BIZ UDP明朝 */
 }
 
 @font-face {
   font-family: "sans-serif-ja";
-  src: local("ＭＳ Ｐゴシック"),
-       local("MS PGothic"),
-       local("Hiragino Kaku Gothic Pro W3"),
-       local("ヒラギノ角ゴ Pro W3"),
-       local("Hiragino Sans GB"),
-       local("ヒラギノ角ゴシック W3"),
-       local("游ゴシック"),
-       local("YuGothic"),
-       local("ＭＳ ゴシック"),
-       local("MS Gothic"),
-       local("Hiragino Sans");
+  src: local("ＭＳ Ｐゴシック"), /* for IE */
+       local("MS PGothic"), /* ＭＳ Ｐゴシック */
+       local("HiraginoSans-W3"), local("Hiragino Sans"), /* ヒラギノ角ゴシック */
+       local("HiraKakuProN-W3"), local("Hiragino Kaku Gothic ProN"), /* ヒラギノ角ゴ ProN W3 */
+       local("HiraKakuPro-W3"), local("Hiragino Kaku Gothic Pro"), /* ヒラギノ角ゴ Pro W3 */
+       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 Medium"), local("Yu Gothic"), /* 游ゴシック(Windows) "Yu Gothic" is a fallback. */
+       local("BIZ UDPGothic"); /* BIZ UDPゴシック */
 }
 
 /* 縦組み用 (vertical writing) */
 
 @font-face {
   font-family: "serif-ja-v";
-  src: local("ＭＳ 明朝"),
-       local("MS Mincho"),
-       local("Hiragino Mincho Pro"),
-       local("ヒラギノ明朝 Pro W3"),
-       local("游明朝"),
-       local("YuMincho"),
-       local("ＭＳ Ｐ明朝"),
-       local("MS PMincho"),
-       local("Hiragino Mincho ProN");
+  src: local("ＭＳ 明朝"), /* for IE */
+       local("MS Mincho"), /* ＭＳ 明朝 */
+       local("HiraMinProN-W3"), local("Hiragino Mincho ProN"), /* ヒラギノ明朝 ProN W3 */
+       local("HiraMinPro-W3"), local("Hiragino Mincho Pro"), /* ヒラギノ明朝 Pro W3 */
+       local("YuMin-Medium"), local("YuMincho"), /* 游明朝体(macOS) */
+       local("Yu Mincho"), /* 游明朝(Windows) */
+       local("BIZ UDMincho"); /*  BIZ UD明朝 */
 }
 
 @font-face {
   font-family: "sans-serif-ja-v";
-  src: local("ＭＳ ゴシック"),
-       local("MS Gothic"),
-       local("Hiragino Kaku Gothic Pro W3"),
-       local("ヒラギノ角ゴ Pro W3"),
-       local("Hiragino Sans GB"),
-       local("ヒラギノ角ゴシック W3"),
-       local("游ゴシック"),
-       local("YuGothic"),
-       local("ＭＳ Ｐゴシック"),
-       local("MS PGothic"),
-       local("Hiragino Sans");
+  src: local("ＭＳ ゴシック"), /* for IE */
+       local("MS Gothic"), /* ＭＳ ゴシック */
+       local("HiraginoSans-W3"), local("Hiragino Sans"), /* ヒラギノ角ゴシック */
+       local("HiraKakuProN-W3"), local("Hiragino Kaku Gothic ProN"), /* ヒラギノ角ゴ ProN W3 */
+       local("HiraKakuPro-W3"), local("Hiragino Kaku Gothic Pro"), /* ヒラギノ角ゴ Pro W3 */
+       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 Medium"), local("Yu Gothic"), /* 游ゴシック(Windows)  "Yu Gothic" is a fallback. */
+       local("BIZ UDGothic"); /* BIZ UDゴシック */
 }
\ No newline at end of file
diff --git a/css/src/modules/ReadiumCSS-base.css b/css/src/modules/ReadiumCSS-base.css
index d0ddbb9..bb42e0b 100644
--- a/css/src/modules/ReadiumCSS-base.css
+++ b/css/src/modules/ReadiumCSS-base.css
@@ -117,16 +117,17 @@ math {
 }
 
 :lang(ja) {
-  --RS__baseFontFamily: "游ゴシック体", YuGothic, "ヒラギノ丸ゴ", "Hiragino Sans", "Yu Gothic UI", "Meiryo UI", "MS Gothic", Roboto, Noto, "Noto Sans CJK JP", sans-serif;
+  --RS__baseFontFamily: YuGothic, "Hiragino Maru Gothic ProN", "Hiragino Sans", "Yu Gothic UI", "Meiryo UI", "MS Gothic", Roboto, Noto, "Noto Sans CJK JP", sans-serif;
 
   /* For CJK, the line-height is usually 15–20% more than for Latin */
   --RS__lineHeightCompensation: 1.167;
 
   /* Extra variables for Japanese font-stacks as we may want to reuse them for user settings + default */
-  --RS__serif-ja: "ＭＳ Ｐ明朝", "MS PMincho", "Hiragino Mincho Pro", "ヒラギノ明朝 Pro W3", "游明朝", "YuMincho", "ＭＳ 明朝", "MS Mincho", "Hiragino Mincho ProN", serif;
-  --RS__sans-serif-ja: "ＭＳ Ｐゴシック", "MS PGothic", "Hiragino Kaku Gothic Pro W3", "ヒラギノ角ゴ Pro W3", "Hiragino Sans GB", "ヒラギノ角ゴシック W3", "游ゴシック", "YuGothic", "ＭＳ ゴシック", "MS Gothic", "Hiragino Sans", sans-serif;
-  --RS__serif-ja-v: "ＭＳ 明朝", "MS Mincho", "Hiragino Mincho Pro", "ヒラギノ明朝 Pro W3", "游明朝", "YuMincho", "ＭＳ Ｐ明朝", "MS PMincho", "Hiragino Mincho ProN", serif;
-  --RS__sans-serif-ja-v: "ＭＳ ゴシック", "MS Gothic", "Hiragino Kaku Gothic Pro W3", "ヒラギノ角ゴ Pro W3", "Hiragino Sans GB", "ヒラギノ角ゴシック W3", "游ゴシック", "YuGothic", "ＭＳ Ｐゴシック", "MS PGothic", "Hiragino Sans", sans-serif;
+  /* 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", "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", "Yu Gothic Medium", "BIZ UDGothic", "Yu Gothic", "ＭＳゴシック", "MS Gothic", sans-serif;
 }
 
 :lang(km) {