\begin{tabular}[c]{|m{1.5cm}||m{3.2cm}||m{3.2cm}||m{3.2cm}||m{3.2cm}||m{3.2cm}||m{2.5cm}||m{2.5cm}|}

\hhline{:-::-::-::-::-::-::-::-:} \centering{\textcolor{blue}{Time}}& \centering{\textcolor{blue}{Mon}} & \centering{\textcolor{blue}{Tue}} & \centering{\textcolor{blue}{Wed}} & \centering{\textcolor{blue}{Thu}} & \centering{\textcolor{blue}{Fri}} & \centering{\textcolor{blue}{Sat}} & \centering{\textcolor{blue}{Sun}} \\ \hhline{:=::=::=::=::=::=::=::=:}

\centering{-1\\(07:00$\sim$ \\07:50)} & & & & & & & \\

\hhline{:=::=::=::=::=::=::=::=:}

\centering{0\\(08:00$\sim$ \\08:50)} & & & & & & & \\

\hhline{:=::=::=::=::=::=::=::=:}

.. 

여기서 

! Misplaced \omit.

\hhline #1->\omit

\@firstamptrue \@tempswafalse \global \setbox \@ne \HH@box...

l.14 ...Sun}} \\ \hhline{:=::=::=::=::=::=::=::=:}

?

이런 오류가 나는데 어떻게 하죠?

그리고 \usepackage{colortbl} 을 쓰면 

겹 가로줄 사이에 자동으로 검정색이 칠해지는데 왜 그러죠?

이렇게요 ㅠ