diff --git a/resources/templates/book_details.css b/resources/templates/book_details.css
index 5cabf7dc96..21f108a0da 100644
--- a/resources/templates/book_details.css
+++ b/resources/templates/book_details.css
@@ -29,7 +29,10 @@ table.fields td {
 }
 
 table.fields td.title {
-    font-weight: bold
+    font-weight: normal;
+    font-style: italic;
+    color: palette(placeholder-text);
+    text-align: right;
 }
 
 .series_name {
diff --git a/src/calibre/ebooks/metadata/book/render.py b/src/calibre/ebooks/metadata/book/render.py
index fe910b9891..7440d0af0b 100644
--- a/src/calibre/ebooks/metadata/book/render.py
+++ b/src/calibre/ebooks/metadata/book/render.py
@@ -93,7 +93,7 @@ def mi_to_html(
         mi,
         field_list=None, default_author_link=None, use_roman_numbers=True,
         rating_font='Liberation Serif', rtl=False, comments_heading_pos='hide',
-        for_qt=False, vertical_fields=(), show_links=True, gray='#7f7f7f',
+        for_qt=False, vertical_fields=(), show_links=True,
     ):
 
     link_markup =  '↗️'
@@ -426,11 +426,7 @@ def mi_to_html(
         classname(fieldl), html) for fieldl, html in ans]
     # print '\n'.join(ans)
     direction = 'rtl' if rtl else 'ltr'
-    rans = (
-        '<style>table.fields td { vertical-align:top} table.fields td.title {'
-        f'text-align: right; color: {gray}; font-style: italic; font-weight: normal '
-        '}</style>'
-        '<table class="fields" style="direction: %s; ' % direction)
+    rans = f'<table class="fields" style="direction: {direction}; '
     if not for_qt:
         # This causes wasted space at the edge of the table in Qt's rich text
         # engine, see https://bugs.launchpad.net/calibre/+bug/1881488
diff --git a/src/calibre/gui2/book_details.py b/src/calibre/gui2/book_details.py
index 9e2d075b0e..0ae2ecd580 100644
--- a/src/calibre/gui2/book_details.py
+++ b/src/calibre/gui2/book_details.py
@@ -292,15 +292,11 @@ def render_data(mi, use_roman_numbers=True, all_fields=False, pref_name='book_di
     field_list = get_field_list(getattr(mi, 'field_metadata', field_metadata),
                                 pref_name=pref_name, mi=mi)
     field_list = [(x, all_fields or display) for x, display in field_list]
-    gray = '#666'
-    app = QApplication.instance()
-    if app is not None and app.is_dark_theme:
-        gray = app.palette().color(QPalette.ColorRole.PlaceholderText).name()
     return mi_to_html(
         mi, field_list=field_list, use_roman_numbers=use_roman_numbers, rtl=is_rtl(),
         rating_font=rating_font(), default_author_link=default_author_link(),
         comments_heading_pos=gprefs['book_details_comments_heading_pos'], for_qt=True,
-        vertical_fields=vertical_fields, show_links=show_links, gray=gray
+        vertical_fields=vertical_fields, show_links=show_links
     )
 
 # }}}
@@ -980,6 +976,10 @@ class BookInfo(HTMLDisplay):
         html = render_html(mi, self.vertical, self.parent())
         set_html(mi, html, self)
 
+    def process_external_css(self, css):
+        col = self.palette().color(QPalette.ColorRole.PlaceholderText).name() if QApplication.instance().is_dark_theme else '#666'
+        return css.replace('palette(placeholder-text)', col)
+
     def mouseDoubleClickEvent(self, ev):
         v = self.viewport()
         if v.rect().contains(self.mapFromGlobal(ev.globalPos())):
diff --git a/src/calibre/gui2/comments_editor.py b/src/calibre/gui2/comments_editor.py
index 19225ef03b..49a41b668e 100644
--- a/src/calibre/gui2/comments_editor.py
+++ b/src/calibre/gui2/comments_editor.py
@@ -288,7 +288,7 @@ class EditorWidget(QTextEdit, LineEditECM):  # {{{
     def __init__(self, parent=None):
         QTextEdit.__init__(self, parent)
         self.setTabChangesFocus(True)
-        self.document().setDefaultStyleSheet(css() + '\n\nli { margin-top: 0.5ex; margin-bottom: 0.5ex; }')
+        self.document().setDefaultStyleSheet(css().replace('palette(placeholder-text)', 'gray') + '\n\nli { margin-top: 0.5ex; margin-bottom: 0.5ex; }')
         font = self.font()
         f = QFontInfo(font)
         delta = tweaks['change_book_details_font_size_by'] + 1
diff --git a/src/calibre/gui2/markdown_editor.py b/src/calibre/gui2/markdown_editor.py
index 6d946c746c..38fe135e95 100644
--- a/src/calibre/gui2/markdown_editor.py
+++ b/src/calibre/gui2/markdown_editor.py
@@ -17,7 +17,7 @@ class Preview(HTMLDisplay):
 
     def __init__(self, parent=None):
         super().__init__(parent)
-        self.setDefaultStyleSheet(css())
+        self.setDefaultStyleSheet(css().replace('palette(placeholder-text)', 'gray'))
         self.setTabChangesFocus(True)
         self.base_url = None
 
diff --git a/src/calibre/gui2/widgets2.py b/src/calibre/gui2/widgets2.py
index 65f58ee054..07a0871e68 100644
--- a/src/calibre/gui2/widgets2.py
+++ b/src/calibre/gui2/widgets2.py
@@ -547,7 +547,7 @@ class HTMLDisplay(QTextBrowser):
 
     def setDefaultStyleSheet(self, css=''):
         self.external_css = css
-        self.document().setDefaultStyleSheet(self.default_css + self.external_css)
+        self.document().setDefaultStyleSheet(self.default_css + self.process_external_css(self.external_css))
 
     def palette_changed(self):
         app = QApplication.instance()
@@ -557,9 +557,12 @@ class HTMLDisplay(QTextBrowser):
             self.default_css = 'a { color: %s }\n\n' % col.name(QColor.NameFormat.HexRgb)
         else:
             self.default_css = ''
-        self.document().setDefaultStyleSheet(self.default_css + self.external_css)
+        self.document().setDefaultStyleSheet(self.default_css + self.process_external_css(self.external_css))
         self.setHtml(self.last_set_html)
 
+    def process_external_css(self, css):
+        return css
+
     def on_anchor_clicked(self, qurl):
         if not qurl.scheme() and qurl.hasFragment() and qurl.toString().startswith('#'):
             frag = qurl.fragment(QUrl.ComponentFormattingOption.FullyDecoded)