SVG definitely sounds like the best/easiest way to do what you want.
You can build out your base mall map in any vector art tool, such as Adobe Illustrator or Inkscape. From there, you can use normal CSS to style the elements.
https://developer.mozilla.org/en-US/docs/Web/SVG/Tutorial/SVG_and_CSS
<circle id="overlay" cx="0" cy="0" r="200" stroke="none" />
Then in your CSS:
#overlay {
fill: #f3f;
}
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