diff --git a/README.md b/README.md
index bd9da5c..63805c6 100644
--- a/README.md
+++ b/README.md
@@ -121,13 +121,14 @@ https://sdq.kastel.kit.edu/wiki/BibTeX-Literaturlisten
 ---------------
 Document class for CEL presentations in KIT design.
 
-`packages/packages.tex`
+`preambles/packages.tex`
 -----------------------
 A TeX file to load all the necessary packages. Current version inherient from the old (before 2025) CEL beamer template.
 
-`packages/macros.tex`
+`preambles/macros.tex`
 --------------------
 A TeX file containing some commonly used macros.
+`introduction.tex` includes examples of some predefiend macros.
 
 `logos/`
 --------
diff --git a/images/IMG_7829-cut.jpeg b/images/IMG_7829-cut.jpeg
new file mode 100644
index 0000000..66ef226
Binary files /dev/null and b/images/IMG_7829-cut.jpeg differ
diff --git a/images/IMG_7832-cut.jpeg b/images/IMG_7832-cut.jpeg
new file mode 100644
index 0000000..9898238
Binary files /dev/null and b/images/IMG_7832-cut.jpeg differ
diff --git a/images/castleflagcut.jpeg b/images/castleflagcut.jpeg
new file mode 100644
index 0000000..c0c8583
Binary files /dev/null and b/images/castleflagcut.jpeg differ
diff --git a/introduction.tex b/introduction.tex
index 3e43a06..2b632b6 100644
--- a/introduction.tex
+++ b/introduction.tex
@@ -4,7 +4,7 @@
 %% Modified by: Hedongliang Liu
 %% Last modified on: 14.08.2025
 %%%%%%%%%%% CEL beamer class %%%%%%%%%%%%%%%
-\documentclass[kitgrid, overviewatsection, showsubsectionsatfirstoverview]{CELbeamer} 
+\documentclass[overviewatsection, showsubsectionsatfirstoverview]{CELbeamer} 
 %% default options: en, helvet, bigfoot (12pt)
 %% other options: de, franklin, smallfoot (11pt), navbaron, kitgrid, handout, 
 %% spaceforface, overviewatsection, showsubsectionsatfirstoverview
@@ -49,11 +49,29 @@
 
 % Start of the presentation
 % Title page
-
-\begin{frame}[title white vertical, picture=images/castleflagcut]
+% KIT Campus South gate
+\begin{frame}[title white vertical, picture=images/IMG_7832-cut]
+	\titlepage
+\end{frame}
+\begin{frame}[title white vertical, picture=images/IMG_7829-cut]
 	\titlepage
 \end{frame}
 
+% KA palace north
+\begin{frame}[title white vertical, picture=images/IMG_7801-cut]
+	\titlepage
+\end{frame}
+\begin{frame}[title white vertical, picture=images/IMG_7798-cut]
+	\titlepage
+\end{frame}
+\begin{frame}[title white vertical, picture=images/IMG_7798-2]
+	\titlepage
+\end{frame}
+
+% KA palace front
+\begin{frame}[title white vertical, picture=images/castleflagcut]
+	\titlepage
+\end{frame}
 % \begin{frame}[tableofcontents=blue]{Overview}
 % 	\tableofcontents
 % \end{frame}
@@ -65,12 +83,13 @@
 \begin{itemize}
 	\item \texttt{en} \textit{(default)} for English, \texttt{de} for German
 	\item \texttt{helvet} \textit{(default)} for Helvetica font, \texttt{franklin} for Franklin Gothic font
-	\item \texttt{bigfoot} \textit{(default)} for 12pt font size, \texttt{smallfoot} for 11pt font size
+	\item \texttt{bigfoot} \textit{(default)} sets the footer font size as 12pt; \texttt{smallfoot} sets the footer font size as 11pt.
 	\item \texttt{navbaron} to show the navigation bar
 	\item \texttt{kitgrid} to show the grid of rows and columns
 	\item<2-> \texttt{handout} to create a handout version of the slides
 	\item<2-> \texttt{spaceforface} to leave space for face in recording 
 	\item<2-> \texttt{overviewatsection} to show the table of contents at each section
+	\item<2-> \texttt{showsubsectionsatfirstoverview} to show all subsections at the first overview
 \end{itemize}
 \end{frame}
 \begin{frame}{Font Size Examples}
@@ -228,13 +247,17 @@
 \begin{frame}[plain]
     % Bei Frames mit Option \texttt{[plain]} werden weder Kopf- noch Fußzeile angezeigt.
 	With frames with the option \texttt{[plain]}, neither header nor footer are displayed.
-	\\
-	The command \texttt{$\backslash$pagesNotes\{<label>\}} can be used to create a page with grid lines for notes, shown on the next slide. \\
-	\texttt{$\backslash$refnotes{<label>}} creates a symbol linked to the page with notes. \refnotes{note1}
 \end{frame}
 
 \subsection{Grid Page for Hand-written Notes}
-\pagesNotes{note1}
+\begin{frame}{Notes Page with Grid Lines}
+	The command \texttt{$\backslash$pagesNotes\{<label>\}\{<subtitle of the note page>\}} can be used to create a page with grid lines for notes, shown on the next slide. \\
+	\texttt{$\backslash$refnotes{<label>}} creates a symbol linked to the page with notes. \\
+	Let's learn more about entropy! \refnotes{note1}\\
+	Let's learn more about divergence! \refnotes{note2}
+\end{frame}
+\pagesNotes{note1}{Entropy}
+\pagesNotes{note2}{Divengence}
 
 \subsection{Footnotes}
 \begin{frame}{Footnotes}
@@ -343,13 +366,11 @@ E.g.,
 \beginbackup
 
 
-\begin{frame}[allowframebreaks]{References}
+\begin{frame}{Backup Parts}
 \begin{exampleblock}{Backup Parts}
     % Folien, die nach \texttt{\textbackslash beginbackup} eingefügt werden, zählen nicht in die Gesamtzahl der Folien.
 	Slides that are inserted after \texttt{\textbackslash beginbackup} do not count towards the total number of slides.
 \end{exampleblock}
-\todo{Fix the bibliography issue.}
-% \printbibliography
 \end{frame}
 
 \begin{frame}{KIT Color Palette}\label{frame:kit-colors}
diff --git a/preambles/macros.tex b/preambles/macros.tex
index 7adf248..e22be22 100644
--- a/preambles/macros.tex
+++ b/preambles/macros.tex
@@ -31,23 +31,28 @@
 		$\hfill \textcolor{kit-green}{\rule{2mm}{2mm}}$
 	\fi}
 
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%%
+%%%   Notes page with grid lines
+%%%
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 % put a page with grid lines for live notes
-% #1 is an index associated with the page, to be used with \notes{#1}
-\newcommand{\pagesNotes}[1]{
-	\bgroup
-	\begin{frame}[c, shrink]{\ifgerman{Notizen}\else{Notes}\fi}
+% #1 is an index associated with the page, to be used with \refnotes{#1}
+% #2 is the title of the notes page
+\newcommand{\pagesNotes}[2]{
+	% \bgroup
+	\begin{frame}[c, shrink]{\ifgerman{Notizen}\else{Notes}\fi}{#2}
+		% [c] means centered, [t] means top-aligned, [b] means bottom-aligned
+		% [shrink] means to shrink the content to fit the frame
         \label{pagesNotes:#1}
 		\vspace*{0.2ex}\hspace*{0ex}
-%
 			\begin{tikzpicture}
 			%\draw[lightgray, line width = .0 mm, step=.25] (0,0) grid (18.5,7);
 			[domain=0:1,scale=3.6]%
 			\draw[very thin,color=white!70!gray,xstep=0.1,ystep=0.1] (0,0) grid (8.71, 3.61);%
-	
 			\end{tikzpicture}
-%		\end{center}
 	\end{frame}
-	\egroup
+	% \egroup
 }
 % Command for showing that some notes will be taken (blackboard, slides,...)
 % #1 is the label for the page of the note