visual studio code import custom css and js extension

I wish to install custom styles to have different font for classes and attributes in visual studio code, however I can't achieve that. I installed extension Custom CSS and JS Loader, and followed the guide but it doesn't seem to work... So basically I created file styles.css where I put this code:

.mtk1,
.mtk2,
.mtk8,
.mtk9,
.mtk10,
.mtk12,
.mtk11,
.mtk7,
.mtk3,
.mtk13,
.mtk16 {
  margin-left: 1px;
  font-family: "Indie Flower";
  font-size: 1em;

}

.mtk7,
.mtk4 {
  font-family: "Arial";
  font-size: 0.7em;
}

/*
  For the tab titles.
*/
.monaco-icon-label-description-container .label-name {
  font-family: "Indie Flower";
  font-size: 1.3em;
}

.tabs-container .monaco-icon-label-description-container .label-name,
.sidebar .monaco-icon-label-description-container .label-name,
.quick-open-row .monaco-icon-label-description-container .label-name {
  font-family: -apple-system,BlinkMacSystemFont,Segoe WPC,Segoe UI,HelveticaNeue-Light,Ubuntu,Droid Sans,sans-serif;
  font-size: 1em;
}

then In settings.json I added:

"vscode_custom_css.imports": ["file:///home/mat/vscode_extensions/styles.css"],
 "vscode_custom_css.policy": true,

I took the path by typing inside this directory "pwd". So it should be correct path however it still doesn't want to apply styles, neither fontFamily nor fontSize. Does anyone knows where the problem is?