\ProvidesPackage{ptbposter-tcb}[2020/02/13 v0.1c ptbposter/tcolorbox (RN)]

\newcommand*\PTB@posterSet{%
  columns=3,rows=5,spacing=\PTB@texthsep,showframe=false,}
\newcommand*\posterSet[1]{%
  \g@addto@macro\PTB@posterSet{#1}%
}

\RequirePackage[most]{tcolorbox}
\tcbuselibrary{poster}
\usetikzlibrary{shadings,arrows.meta}

\colorlet{backgroundTop}{Goldenrod2!10}
\colorlet{backgroundBottom}{Goldenrod2!90}
\colorlet{boxBackground}{white}

\renewcommand*\backgroundContent{%
  \begin{tikzpicture}%
    \shade[top color=backgroundTop, bottom color=backgroundBottom,%
      shading angle=\ifPTBlandscape 64.07\else 41.55\fi](0,0)%
      % Winkel auf Basis von \PTB@framewidth und \PTB@frameheight
      rectangle(\PTB@framewidth,\PTB@frameheight);%
  \end{tikzpicture}%  
}

\tcbposterset{%    
  coverage={%
    height=\textheight,
    width=\textwidth,
    interior style={opacity=0},
    top=0pt,bottom=0pt,left=0pt,right=0pt
  },%
  boxes={
    enhanced standard jigsaw,%sharp corners=downhill,
    arc=0.012\PTB@scale@base,
    boxrule=\PTB@framethickness,
    boxsep=0pt,
    top=1ex,bottom=1ex,left=1ex,right=1ex,
    toptitle=.6ex,bottomtitle=.6ex,lefttitle=1ex,righttitle=1ex,
    %before title pre=\strut, 
    colback=boxBackground,
    %opacityback=0.75,% ????
    colframe=PTBcolor,
    coltitle=white,
    fonttitle=\sffamily\bfseries\centering,
    title style={PTBcolor},
    valign=top% center
  }
}%

\AtBeginDocument{%
  \edef\PTB@tempa{\noexpand\tcbposterset{poster={\PTB@posterSet}}}%
  \PTB@tempa
  \begin{tcbposter}%
}
\AtEndDocument{%
  \end{tcbposter}%
}

\endinput