Examine source code of Rather Blue

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Rather Blue",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.jpg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "center top"
      ],
      "additional_backgrounds_tiling": [
        "no-repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(0, 22, 255, 0)",
      "toolbar_text": "rgb(154, 198, 251)",
      "frame": "rgb(8, 11, 31)",
      "tab_background_text": "rgb(170, 214, 249)",
      "toolbar_field": "rgb(25, 34, 99)",
      "toolbar_field_text": "rgb(138, 202, 247)",
      "tab_line": "rgb(130, 197, 250)",
      "popup": "rgb(24, 34, 65)",
      "popup_text": "rgb(151, 196, 251)",
      "tab_loading": "rgb(130, 197, 250)"
    }
  }
}