使用旋转框将表格中的单元格垂直居中

Question

我需要帮助使带有文本和 rotatebox 元素的 tabularx 单元格垂直居中。

这是我的代码（编辑：根据评论更新了代码片段）：

\documentclass{article}

\usepackage{tabularx}
\usepackage{graphicx}
\usepackage{relsize}
\usepackage{multirow}
\usepackage{booktabs}

\begin{document}

\begin{table*}
\smaller
\caption{A Table}
\centering

\begin{tabularx}{\textwidth}{llllllllllllXXXlX}

\multirow{2}{*}{} & 
\multicolumn{4}{c}{Multi-1} & 
\multicolumn{4}{c}{Multi-2} & 
\multicolumn{8}{c}{Multi-3}  \\

\cmidrule(lr){2-5}
\cmidrule(lr){6-9}
\cmidrule(lr){10-17}

\multicolumn{1}{l|}{\rotatebox{90}{Ref}} & 

\multicolumn{1}{l|}{\rotatebox{90}{very-long-rotate-1}}& 
\multicolumn{1}{l|}{\rotatebox{90}{very-long-rotate-2}} &
\multicolumn{1}{l|}{\rotatebox{90}{very-long-rotate-3}}&
\multicolumn{1}{l|}{\rotatebox{90}{very-long-rotate-4}} & 

\multicolumn{1}{l|}{\rotatebox{90}{very-long-rotate-1}} & 
\multicolumn{1}{l|}{\rotatebox{90}{very-long-rotate-2}} &
\multicolumn{1}{l|}{\rotatebox{90}{very-long-rotate-3}} &
\multicolumn{1}{l|}{\rotatebox{90}{very-long-rotate-4}} & 

\multicolumn{1}{l|}{\rotatebox{90}{very-long-rotate-1}} &
\multicolumn{1}{l|}{\rotatebox{90}{very-long-rotate-2}} &
\multicolumn{1}{l|}{\rotatebox{90}{very-long-rotate-3}} & 

\multicolumn{1}{c|}{center} &  
\multicolumn{1}{c|}{center} & 
\multicolumn{1}{c|}{center} & 

\multicolumn{1}{l|}{\rotatebox{90}{very-long-rotate-1}} & 

\multicolumn{1}{c|}{center} \\ 
\cmidrule{1-17}
                  &  &  &  &                &  &  &  &                  &  &  &  &  &  &  &  &                 \\
              
\end{tabularx}
\end{table*}

并呈现下表：

我想要有带文本的列中心垂直（以及水平）居中。你能帮助我吗？

提前致谢