扩大子标题后的间距（子标题包）

Question

当我使用该subcaption包时，子标题和其下方的图像之间只有非常小的空白。

我可以使用“\bigskip”添加大空格，但我想知道是否有命令可以全局更改空格量。

\documentclass{article}

\usepackage[demo]{graphicx}
\usepackage[font={small}, justification=centering]{caption}
\usepackage[labelformat=simple]{subcaption}
\renewcommand\thesubfigure{(\alph{subfigure})}
\captionsetup[subfigure]{position=below,skip=25pt}
\usepackage{lipsum}

\begin{document}

\lipsum[1]

\begin{figure}[!htbp]
\subcaptionbox{heading}{\includegraphics[width=0.49\linewidth]{imagefile}}%
\hfill
\subcaptionbox{heading}{\includegraphics[width=0.49\linewidth]{imagefile}}

\subcaptionbox{heading}{\includegraphics[width=0.49\linewidth]{imagefile}}%
\hfill
\subcaptionbox{heading}{\includegraphics[width=0.49\linewidth]{imagefile}}

\caption{text text text text text text text text text text text text text} 
\end{figure}

\lipsum[1]

\end{document}

Answer 1

放\belowcaptionskip。

\documentclass[]{article}

\usepackage[demo]{graphicx}
\usepackage[font={small}, justification=centering]{caption}
\usepackage[labelformat=simple]{subcaption}
\renewcommand\thesubfigure{(\alph{subfigure})}
\captionsetup[subfigure]{position=below,skip=1em}
\usepackage{blindtext}

\begin{document}
    \setlength\belowcaptionskip{1em}
    
    \blindtext[1]
    \begin{figure}[!htbp]
        \subcaptionbox{heading}{\includegraphics[width=0.5\linewidth]{imagefile}}
        \subcaptionbox{heading}{\includegraphics[width=0.5\linewidth]{imagefile}}\\
        \subcaptionbox{heading}{\includegraphics[width=0.5\linewidth]{imagefile}}
        \subcaptionbox{heading}{\includegraphics[width=0.5\linewidth]{imagefile}}
        \caption{text text text text text text text text text text text text text} 
    \end{figure}
    
    \blindtext[1]
\end{document}