Examine source code of Kobenhavntheme

{
  "name": "affiche-de-ville-de-copenhague-89910924",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "affiche-de-ville-de-copenhague-89910924.jpg"
    },
    "colors": {
      "frame": "rgba(220, 202, 227, 1)",
      "tab_background_text": "rgba(224, 204, 204, 1)",
      "toolbar": "rgba(240, 221, 221, 1)",
      "bookmark_text": "rgba(194, 184, 184, 1)",
      "toolbar_field": "rgba(255, 254, 250, 1)",
      "toolbar_field_text": "rgba(219, 237, 192, 1)"
    }
  }
}