\usepackage{etoolbox}
\usepackage[most]{tcolorbox}
\usepackage{graphicx}
\usepackage{xparse}
\tcbuselibrary{breakable}

\definecolor{speculativeback}{RGB}{247,232,255}  % #f7e8ff
\definecolor{speculativeframe}{RGB}{139,43,226}  % #8b2be2

% Helper to show a blank title if empty
\newcommand{\blanktitle}{\mbox{}}

% =========================================================
% Concept Boxes
% =========================================================
\newtcolorbox{proposedbox}[1][Proposed Concept]{%
  title=\ifstrempty{#1}{\blanktitle}{#1},
  colback=blue!5!white,
  colframe=blue!75!black,
  colbacktitle=blue!15!white,
  fonttitle=\bfseries,
  coltitle=black,
  enhanced, sharp corners, breakable,
  after=\par\vspace{6pt}
}

\newtcolorbox{establishedbox}[1][Established Concept]{%
  title=\ifstrempty{#1}{\blanktitle}{#1},
  colback=green!5!white,
  colframe=green!75!black,
  colbacktitle=green!15!white,
  fonttitle=\bfseries,
  coltitle=black,
  enhanced, sharp corners, breakable,
  after=\par\vspace{6pt}
}

\newtcolorbox{speculativebox}[1][Speculative Concept]{%
  title=\ifstrempty{#1}{\blanktitle}{#1},
  colback=speculativeback,
  colframe=speculativeframe,
  colbacktitle=speculativeback!80!white, % lighter variant for title bar
  fonttitle=\bfseries,
  coltitle=black,
  enhanced, sharp corners, breakable,
  after=\par\vspace{6pt}
}


\newtcolorbox{cautionbox}[1][Caution]{%
  title=\ifstrempty{#1}{\blanktitle}{#1},
  colback=orange!5!white,
  colframe=orange!75!black,
  colbacktitle=orange!15!white,
  fonttitle=\bfseries,
  coltitle=black,
  enhanced, sharp corners, breakable,
  after=\par\vspace{6pt}
}

\newtcolorbox{warningbox}[1][Warning]{%
  title=\ifstrempty{#1}{\blanktitle}{#1},
  colback=orange!5!white,
  colframe=orange!75!black,
  colbacktitle=orange!15!white,
  fonttitle=\bfseries,
  coltitle=black,
  enhanced, sharp corners, breakable,
  after=\par\vspace{6pt}
}

\newtcolorbox{dangerbox}[1][Danger]{%
  title=\ifstrempty{#1}{\blanktitle}{#1},
  colback=red!5!white,
  colframe=red!75!black,
  colbacktitle=red!15!white,
  fonttitle=\bfseries,
  coltitle=black,
  enhanced, sharp corners, breakable,
  after=\par\vspace{6pt}
}