[Tex/LaTex] Software architecture picture in TikZ

tikz-pgf

I want to make following Software architecture inside TikZ:

enter image description here

See below my code:

\documentclass[border=2px]{standalone}
\usepackage[utf8]{inputenc}
\usepackage{tikz}
\usetikzlibrary{shapes.geometric, arrows}

\tikzset{
    green/.style  = {draw, rectangle, minimum width=1cm, minimum height=1cm, text centered, text width=1.2cm, font=\footnotesize, draw=black, fill=green!30},
    blue/.style   = {draw, rectangle, minimum width=6cm, minimum height=1cm, text centered, text width=5.0cm, font=\footnotesize, draw=black, fill=blue!30},
    yellow/.style = {draw, rectangle, minimum width=6cm, minimum height=1cm, text centered, text width=5.0cm, font=\footnotesize, draw=black, fill=yellow!30},
}

\begin{document}
\begin{tikzpicture}[node distance=1.1cm]
    \node (r1c1) [green] {VC++};
    \node (r1c2) [green, right of=r1c1, xshift=0.5cm] {VB.NET};
    \node (r1c3) [green, right of=r1c2, xshift=0.5cm] {C\#.NET};
    \node (r1c4) [green, right of=r1c3, xshift=0.5cm] {Others};
    \node (r2c1) [blue,  below of=r1c2, xshift=0.8cm] {COM-API Interface};
    \node (r3c1) [yellow, below of=r2c1] {Autodesk Inventor Application};

    \draw (r1c1);
    \draw (r1c2);
    \draw (r1c3);
    \draw (r1c4);
    \draw (r2c1);
    \draw (r3c1);
\end{tikzpicture}
\end{document}

Below is the generated diagram:

enter image description here

The modules inside generated diagram are not properly aligned. Any suggestions please?

Best Answer

Just for fun and as somebody proposed tcolorbox ...

\documentclass{article}

\usepackage[most]{tcolorbox}

\tcbset{enhanced, fontupper=\bfseries, notitle, sharp corners, halign=center, valign=center}

\begin{document}
\begin{tcbitemize}[%
    raster equal height=rows, 
    raster columns=4,
    raster equal height,
    raster every box/.style={height=2cm},
    raster column skip=1mm,
    raster row skip=1mm,
    colback=green!70!black]
\tcbitem VC++
\tcbitem VB.NET
\tcbitem C\#.NET
\tcbitem Others
\tcbitem[colback=blue!40, raster multicolumn=4]
COM-API Interface
\tcbitem[colback=yellow!50, raster multicolumn=4]
Autodesk Inventor Application
\end{tcbitemize}
\end{document}

enter image description here