Examine source code of Blue Polka

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Blue Polka",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-003-8ef09b1ac3637e1c95fa5c504fdf1a5d.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(40, 92, 101)",
      "toolbar_text": "rgb(255, 255, 255)",
      "frame": "rgb(37, 105, 126)",
      "tab_background_text": "rgb(255, 255, 255)",
      "toolbar_field": "rgb(38, 72, 102)",
      "toolbar_field_text": "rgb(46, 193, 221)",
      "tab_line": "rgb(67, 194, 218)",
      "popup": "rgb(37, 105, 126)",
      "popup_text": "rgb(255, 255, 255)",
      "tab_loading": "rgb(67, 194, 218)"
    }
  }
}