Examine source code of Black Dice

{
  "manifest_version": 2,
  "version": "4.0",
  "name": "Black Dice",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(64, 64, 70, 0.51)",
      "toolbar_text": "rgb(234, 236, 240)",
      "frame": "rgb(0, 0, 0)",
      "tab_background_text": "rgb(174, 175, 177)",
      "toolbar_field": "rgba(82, 82, 84, 0.32)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgb(168, 169, 173)",
      "popup": "rgb(23, 23, 25)",
      "popup_text": "rgb(195, 196, 198)",
      "tab_loading": "rgb(168, 169, 173)"
    }
  }
}