Examine source code of Gray Mod

{
  "theme": {
    "images": {
      "theme_frame": "FF-Persona-Gray-Mod-Top-002.png"
    },
    "colors": {
      "frame": "#c2c2c2",
      "tab_background_text": "#adaeb0"
    }
  },
  "version": "2.0",
  "name": "Gray Mod",
  "manifest_version": 2,
  "description": "Just wanted something that would work nice with \"Tree Style Tab\" Add-On... When you have the tabs to the right there is not much separation between to content and the header... So this draws on a few of my favorite personas and adds a little light gray line at the bottom."
}