How can I adjust this code for a vertical enumerate in documentclass{book}?

Question

\documentclass[border=10pt,tikz,x11names]{standalone}
 \usepackage[outline]{contour}
 \usetikzlibrary{shadows}

 \begin{document}

\begin{tikzpicture}[button/.style 2 args={
    circle, 
    minimum size=0.75cm,
    top color=#1!30!white,
    bottom color=#1,
    draw=#1!90!black,
    thick,
    append after command={
        node[circle,draw=#1!90!white,
        minimum size=0.68cm,
        font=\sffamily]at(\tikzlastnode.center)
        {\textcolor{white}{\contour{#1}{#2}}}
    },
    general shadow={
        shadow xshift=.2ex, shadow yshift=-.2ex,
        opacity=.5, fill=black!50,
    }
}]

\foreach \buttoncolor[count=\i] in {red, 
 DarkOrange1,Goldenrod1,Green3,blue!50!cyan,DarkOrchid2}
\node[button={\buttoncolor}{\i}] at (\i, 0){};

\foreach \buttoncolor[count=\xi,evaluate=\xi as \i using int(13-\xi)] in 
{Azure2,gray!25!white,Snow3,Snow4,black!80!white,black}
\node[button={\buttoncolor}{\i}] at (\xi, -1){};

\end{tikzpicture}
\begin{itemize}
\item 54
\end{itemize}

\end{document}

Answer 1

This answer is based on https://tex.stackexchange.com/a/50452/90297 .

The difference from your MWE:

1. Used the book document class as requested.
2. Put the circled in a newcommand as in the old answer.

Differences from previous answer:

1. Notice that unlike the original, here you can take two parameters into your button, enabling you to use different colors in different levels/lists.
2. Used contour and shading as in MWE.

MWE:

\documentclass{book}
\usepackage{tikz}
\usetikzlibrary{shadows}
\usepackage[outline]{contour}
\newcommand*\circled[2]{
            \tikz[
                baseline=(char.base)
            ]{%
            \node[shape=circle,
                  minimum size=0.75cm,
                  top color=#1!30!white,
                  bottom color=#1, 
                  draw=#1!90!black,
                  append after command={
                    node[circle,draw=#1!90!white,
                    minimum size=0.68cm,
                    font=\sffamily]at(\tikzlastnode.center)
                    {\textcolor{white}{\contour{#1}{#2}}}
                  },
                  thick,
                  general shadow={
                    shadow xshift=.2ex, shadow yshift=-.2ex,
                    opacity=.5, fill=black!50,
                  }
                  ] (char) {#2};}}
\usepackage{enumitem}
\usepackage{xcolor}
\begin{document}
\begin{enumerate}[label=\protect\circled{red}{\arabic*}]
\item Step one%
\item Step two%
\item Step three%
\end{enumerate}
\end{document}