Examine source code of Just a black theme

{
  "manifest_version": 2,
  "version": "1.1",
  "name": "Just a black theme",
  "author": "Johan August Oestbye",
  "theme": {
    "colors": {
      "toolbar": "rgb(13, 13, 13)",
      "toolbar_text": "rgb(217, 217, 217)",
      "frame": "rgb(0, 0, 0)",
      "tab_background_text": "rgb(217, 217, 217)",
      "toolbar_field": "rgb(21, 21, 21)",
      "toolbar_field_text": "rgb(247, 247, 247)",
      "tab_line": "rgba(6, 6, 6, 0)",
      "popup": "rgb(18, 18, 18)",
      "popup_text": "rgb(217, 217, 217)",
      "tab_selected": "rgb(21, 21, 21)",
      "tab_loading": "rgba(6, 6, 6, 0)"
    }
  }
}