% Cover page — a hand-drawn "agent motif": a central AI core with radiating
% arms ending in tool glyphs (the "one agent + many tools" idea). Pure vector
% TikZ, navy line art on white — no external image, fully reproducible. The
% build date is stamped near the bottom so successive versions are distinguishable.
\begin{titlepage}
\thispagestyle{empty}
% Thin navy top band + footer rule (series look; no tagline text).
\begin{tikzpicture}[remember picture, overlay]
  \fill[structurecolor] (current page.north west) rectangle ([yshift=-0.85cm]current page.north east);
  \fill[structurecolor] (current page.south west) rectangle ([yshift=0.5cm]current page.south east);
\end{tikzpicture}
\centering
\vspace*{2.5cm}

{\fontsize{37}{46}\selectfont\rmfamily\bfseries 深入理解 AI Agent\par}
\vspace{0.5cm}
{\Large\sffamily\color{structurecolor} 设计原理与工程实践\par}

\vspace{1.5cm}

% ── Agent motif: central core + radiating arms ending in tool glyphs ──
\begingroup
\definecolor{ink}{RGB}{30,58,107}
\begin{tikzpicture}[line join=round, line cap=round,
    arm/.style={ink, line width=1.1pt},
    ring/.style={ink, line width=1.1pt, fill=white},
    ic/.style={ink, line width=0.8pt}]
  \def\R{3.15}    % arm length (hub centre → tool node)
  \def\rh{0.98}   % hub radius

  % arms first, so tool nodes sit on top of their ends
  \foreach \a in {90,45,0,-45,-90,-135,180,135}{
    \draw[arm] (\a:\rh) to[bend left=8] (\a:\R);
  }

  % hub (the "agent core") + a 4-point AI spark inside
  \fill[ink!7] (0,0) circle (\rh);
  \draw[ink, line width=1.3pt] (0,0) circle (\rh);
  \fill[ink] (0,0.52) -- (0.13,0.13) -- (0.52,0) -- (0.13,-0.13) --
             (0,-0.52) -- (-0.13,-0.13) -- (-0.52,0) -- (-0.13,0.13) -- cycle;

  % ── tool nodes (r=0.52) with a simple glyph each ──
  % 90° — search (magnifier)
  \begin{scope}[shift={(90:\R)}]
    \draw[ring] (0,0) circle (0.52);
    \draw[ic] (-0.05,0.06) circle (0.15);
    \draw[ic] (0.06,-0.05) -- (0.20,-0.19);
  \end{scope}
  % 45° — code </>
  \begin{scope}[shift={(45:\R)}]
    \draw[ring] (0,0) circle (0.52);
    \draw[ic] (-0.06,0.17) -- (-0.21,0) -- (-0.06,-0.17);
    \draw[ic] (0.06,0.17) -- (0.21,0) -- (0.06,-0.17);
  \end{scope}
  % 0° — terminal
  \begin{scope}[shift={(0:\R)}]
    \draw[ring] (0,0) circle (0.52);
    \draw[ic] (-0.24,-0.17) rectangle (0.24,0.17);
    \draw[ic] (-0.15,0.07) -- (-0.07,0) -- (-0.15,-0.07);
    \draw[ic] (0.01,-0.08) -- (0.15,-0.08);
  \end{scope}
  % -45° — document
  \begin{scope}[shift={(-45:\R)}]
    \draw[ring] (0,0) circle (0.52);
    \draw[ic] (-0.15,-0.21) -- (-0.15,0.21) -- (0.07,0.21) -- (0.17,0.11) -- (0.17,-0.21) -- cycle;
    \draw[ic] (0.07,0.21) -- (0.07,0.11) -- (0.17,0.11);
    \draw[ic] (-0.08,0.05) -- (0.10,0.05);
    \draw[ic] (-0.08,-0.05) -- (0.10,-0.05);
  \end{scope}
  % -90° — gear
  \begin{scope}[shift={(-90:\R)}]
    \draw[ring] (0,0) circle (0.52);
    \draw[ic] (0,0) circle (0.13);
    \foreach \g in {0,45,90,135,180,225,270,315}{ \draw[ic] (\g:0.14) -- (\g:0.22); }
    \fill[ink] (0,0) circle (0.035);
  \end{scope}
  % -135° — globe / web
  \begin{scope}[shift={(-135:\R)}]
    \draw[ring] (0,0) circle (0.52);
    \draw[ic] (0,0) circle (0.20);
    \draw[ic] (0,0) ellipse (0.08 and 0.20);
    \draw[ic] (-0.20,0) -- (0.20,0);
  \end{scope}
  % 180° — database
  \begin{scope}[shift={(180:\R)}]
    \draw[ring] (0,0) circle (0.52);
    \draw[ic] (0,0.14) ellipse (0.18 and 0.07);
    \draw[ic] (-0.18,0.14) -- (-0.18,-0.14);
    \draw[ic] (0.18,0.14) -- (0.18,-0.14);
    \draw[ic] (-0.18,0.0) arc[start angle=180, end angle=360, x radius=0.18, y radius=0.07];
    \draw[ic] (-0.18,-0.14) arc[start angle=180, end angle=360, x radius=0.18, y radius=0.07];
  \end{scope}
  % 135° — chat bubble
  \begin{scope}[shift={(135:\R)}]
    \draw[ring] (0,0) circle (0.52);
    \draw[ic, rounded corners=2pt] (-0.20,-0.03) rectangle (0.20,0.21);
    \draw[ic] (-0.11,-0.03) -- (-0.05,-0.16) -- (0.02,-0.03);
    \fill[ink] (-0.10,0.09) circle (0.022);
    \fill[ink] (0,0.09) circle (0.022);
    \fill[ink] (0.10,0.09) circle (0.022);
  \end{scope}
\end{tikzpicture}
\endgroup

\vfill
{\LARGE\sffamily 李博杰\quad 著\par}
\vspace{0.7cm}
{\small\sffamily\color{structurecolor!80} 版本 v1.0 · \number\year 年 \number\month 月 \number\day 日\par}
\vspace{1.2cm}
\end{titlepage}
