Examine source code of Sunlight..

{
  "theme": {
    "images": {
      "theme_frame": "0131----blueviolet--3-sun.jpg"
    },
    "colors": {
      "frame": "#fafafa",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Sunlight..",
  "manifest_version": 2,
  "description": "太陽のかがやき。。\n\n\n\n0131----blueviolet--3-sun●"
}