Examine source code of Developer Dark

{
  "manifest_version": 2,
  "version": "3.0",
  "name": "Developer Dark",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-000-5672c42860d5b06e1058dc477397f3ef.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(57, 63, 76)",
      "toolbar_text": "rgb(238, 239, 239)",
      "frame": "rgb(28, 33, 38)",
      "tab_background_text": "rgb(238, 239, 239)",
      "toolbar_field": "rgb(36, 41, 49)",
      "toolbar_field_text": "rgb(238, 239, 239)",
      "tab_line": "rgb(86, 117, 185)",
      "popup": "rgb(75, 83, 99)",
      "popup_text": "rgb(238, 239, 239)",
      "button_background_active": "rgb(86, 117, 185)",
      "ntp_background": "rgb(28, 33, 38)",
      "ntp_text": "rgb(238, 239, 239)",
      "sidebar_border": "rgb(93, 93, 109)",
      "sidebar_text": "rgb(238, 239, 239)",
      "sidebar": "rgb(61, 66, 79)",
      "tab_loading": "rgb(86, 117, 185)",
      "toolbar_field_border_focus": "rgb(86, 117, 185)",
      "toolbar_field_border": "rgb(77, 88, 101)",
      "toolbar_field_highlight": "rgb(86, 117, 185)",
      "toolbar_field_separator": "rgb(94, 99, 116)"
    }
  }
}