Re-vendor the theme from the trantor fork

Brings in the fixes from porting the first real deck: no header band on
untitled frames, divider titles in TrantorDark, \alert in the accent and
italic quotes, the title page, dividers, and panels usable inside a
document-opened frame, \plainpage, panel geometry pinned against
document overlay styles, a compressible title page bottom space, and
standout panels left out of the frame numbering.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

slides_template/trantor.sty

@@ -48,6 +48,14 @@
 % itemize/enumerate labels in the body colour rather than the class default
 \AddToHook{begindocument}{\colorlet{structure}{TrantorDark}}
 
+% \alert in the accent colour rather than the class's red, as metropolis
+% coloured alerted text from the theme palette
+\AddToHook{begindocument}{\colorlet{alert}{TrantorAccent}}
+
+% beamer set quotations in italic; ported decks expect it
+\AddToHook{env/quote/begin}{\itshape}
+\AddToHook{env/quotation/begin}{\itshape}
+
 % -- Header bar carrying the frame title (hidden on plain pages).
 % headsep is what pads under the title; the height key alone only pads above.
 \geometry{headsep=10pt}
@@ -64,6 +72,41 @@
   \EditInstance{frametitle}{header}{after-vspace = 6mm minus 3mm}%
 }
 
+% -- A frame with no \frametitle gets no header band. ltx-talk draws it
+% unconditionally, which leaves an empty dark slab across the top of every
+% full-bleed image slide. metropolis omitted the bar on untitled frames and
+% decks are written expecting that. \trantorEmptyHeadertrue restores the bar.
+%
+% The band is drawn from \@oddhead, so this replaces \ps@talk; \pagestyle has
+% to be re-issued for the new definition to take.
+\newif\iftrantorEmptyHeader
+\trantorEmptyHeaderfalse
+
+\ExplSyntaxOn
+\cs_new_protected:Npn \trantor@header
+  {
+    \iftrantorEmptyHeader
+      \UseInstance { header } { std }
+    \else
+      % Guard the class internal: a class change should not make this an error.
+      \cs_if_exist:NTF \g__talk_frame_title_tl
+        {
+          \tl_if_empty:NF \g__talk_frame_title_tl
+            { \UseInstance { header } { std } }
+        }
+        { \UseInstance { header } { std } }
+    \fi
+  }
+\cs_set_nopar:Npn \ps@talk
+  {
+    \cs_set_nopar:Npn \@oddhead { \trantor@header \hfil }
+    \cs_set_nopar:Npn \@oddfoot { \UseInstance { footer } { std } }
+    \cs_set_eq:NN \@evenhead \@oddhead
+    \cs_set_eq:NN \@evenfoot \@oddfoot
+  }
+\ExplSyntaxOff
+\pagestyle{talk}
+
 % Like \frametitle, but forces a gap below the title on packed slides where the
 % header's own spacing collapses. The \par gets us into vertical mode first.
 \NewDocumentCommand\stitle{m}{\frametitle{#1}\par\addvspace{4mm}}
@@ -99,6 +142,8 @@
 % -- \appendix: frames after it are numbered among themselves and left out of
 % the total. The count travels through the aux file, so it settles on the
 % second run.
+% ltx-talk gained its own \appendix upstream after 0.3.12; once a release
+% ships it, revisit this in favour of the class's version.
 \newif\iftrantorAppendix
 \trantorAppendixfalse
 \newcommand\trantorMainFrames{\@totalframes}
@@ -107,6 +152,30 @@
   \global\trantorAppendixtrue
   \protected@write\@auxout{}{%
     \string\gdef\string\trantorMainFrames{\the\value{frame}}}%
+  \protected@write\@auxout{}{%
+    \string\gdef\string\trantorMainPanels{\the\value{trantorpanels}}}%
+}
+
+% -- Panels (standout pages) stay out of the frame numbering, as under
+% metropolis, which set noframenumbering on standout frames. The class's frame
+% counter cannot be touched -- notes and property records key on it -- so the
+% panels are counted separately and subtracted for display. The totals travel
+% through the aux file like \trantorMainFrames does.
+\newcounter{trantorpanels}
+\newcounter{trantorpanellast}
+\newcommand\trantorTotalPanels{0}
+\newcommand\trantorMainPanels{\trantorTotalPanels}
+% \immediate: a deferred write would wait for a shipout that never comes.
+\AtEndDocument{%
+  \immediate\write\@auxout{%
+    \string\gdef\string\trantorTotalPanels{\the\value{trantorpanels}}}%
+}
+% Count each panel frame once, though the body may run once per slide.
+\newcommand\trantor@countpanel{%
+  \ifnum\value{trantorpanellast}=\value{frame}\else
+    \stepcounter{trantorpanels}% \stepcounter and \setcounter act globally
+    \setcounter{trantorpanellast}{\value{frame}}%
+  \fi
 }
 
 % Count registers, not macros: pgfmath expands while parsing, and a macro
@@ -116,11 +185,13 @@
 
 \newcommand\trantor@setcounts{%
   \iftrantorAppendix
-    \trantor@n=\numexpr\value{frame}-\trantorMainFrames\relax
+    \trantor@n=\numexpr\value{frame}-\trantorMainFrames
-    \trantor@d=\numexpr\@totalframes-\trantorMainFrames\relax
+      -\value{trantorpanels}+\trantorMainPanels\relax
+    \trantor@d=\numexpr\@totalframes-\trantorMainFrames
+      -\trantorTotalPanels+\trantorMainPanels\relax
   \else
-    \trantor@n=\value{frame}\relax
+    \trantor@n=\numexpr\value{frame}-\value{trantorpanels}\relax
-    \trantor@d=\numexpr\trantorMainFrames\relax
+    \trantor@d=\numexpr\trantorMainFrames-\trantorMainPanels\relax
   \fi
 }
 
@@ -210,6 +281,27 @@
 \ExplSyntaxOff
 
 
+% Run #1 inside the current frame if there is one, else inside a fresh frame.
+% Mirrors the class's \maketitle, so a document can wrap any of these in its
+% own frame and add content alongside -- a \note, or \footline for a revision
+% stamp -- following the beamer idiom.
+\ExplSyntaxOn
+\cs_new_protected:Npn \trantor@inframe #1
+  {
+    \bool_if:NTF \l__talk_frame_bool
+      {#1}
+      { \begin { frame } #1 \end { frame } }
+  }
+\ExplSyntaxOff
+
+% \plainpage: suppress the footer progress bar and frame number on the current
+% frame's pages, as the title, standout, and divider pages do. Use it at the
+% top of a frame, e.g. one holding a full-bleed image.
+\NewDocumentCommand\plainpage{}{%
+  \global\trantorPlainPagetrue
+  \thispagestyle{plain}%
+}
+
 % -- Title page. Drop a logo.png next to your slides, or redefine \titlelogo.
 \newcommand{\titlelogo}{%
   \IfFileExists{logo.png}
@@ -217,9 +309,8 @@
 }
 
 \renewcommand{\maketitle}{%
-  \global\trantorPlainPagetrue
+  \trantor@inframe{%
-  \begin{frame}{}%
+    \plainpage
-    \thispagestyle{plain}%
     \vfill
     \hspace*{0.04\paperwidth}%
     \begin{minipage}{0.82\paperwidth}
@@ -251,18 +342,23 @@
       \end{minipage}%
     \end{minipage}%
     \hspace*{0.04\paperwidth}%
-    \vspace{0.12\paperheight}%
+    % shrinkable, so a long author block compresses this space instead of
-  \end{frame}%
+    % overfilling the fixed frame height
+    \vspace{0.12\paperheight minus 0.08\paperheight}%
+  }%
 }
 
 % -- A full-bleed dark panel with the given body centred in a minipage of the
 % given width.
 \NewDocumentCommand \trantor@panel { m +m } {%
-  \global\trantorPlainPagetrue
+  \trantor@inframe{%
-  \begin{frame}{}%
+    \plainpage
-    \thispagestyle{plain}%
+    \trantor@countpanel
     \noindent
-    \begin{tikzpicture}
+    % overlay=false explicitly: the panel is positioned from its bounding box,
+    % so it breaks if the document sets \tikzstyle{every picture}+=[overlay],
+    % which decks ported from beamer commonly do.
+    \begin{tikzpicture}[overlay=false, remember picture=false]
       \useasboundingbox (0,0) rectangle (\linewidth,-\textheight);
       \fill[TrantorDark]
         (-\Gm@lmargin, \paperheight)
@@ -276,26 +372,29 @@
         \end{minipage}%
       };
     \end{tikzpicture}%
-  \end{frame}%
+  }%
 }
 
 % -- Divider pages: the section title over a progress bar, set on the ordinary
 % light background. Not plain pages: the footer bar and frame number stay.
+% Like the class's \maketitle, the dividers work inside a frame the document
+% opened itself, so beamer's \begin{frame}\sectionpage\note{...}\end{frame}
+% idiom carries over. Called between frames, they open their own.
 \NewDocumentCommand \trantor@divider { +m } {%
-  \begin{frame}{}%
+  \trantor@inframe{%
     \thispagestyle{plain}%
     \vfill
     \centering
     \begin{minipage}{0.52\linewidth}%
       \raggedright
-      {\headerfont\Large\bfseries\trantorSectionTitle\par}%
+      {\color{TrantorDark}\headerfont\Large\bfseries\trantorSectionTitle\par}%
       \vspace{0.4em}%
       \trantorProgressBar{\linewidth}%
       #1%
     \end{minipage}%
     \par
     \vfill
-  \end{frame}%
+  }%
 }
 
 \NewDocumentCommand \sectionpage { } { \trantor@divider{} }
@@ -304,7 +403,7 @@
 \NewDocumentCommand \subsectionpage { } {%
   \trantor@divider{%
     \par\vspace{0.8em}%
-    {\headerfont\large\bfseries\trantorSubsectionTitle\par}%
+    {\color{TrantorDark}\headerfont\large\bfseries\trantorSubsectionTitle\par}%
   }%
 }