Examine source code of 1. Theme von Unklo

{
  "manifest_version": 2,
  "version": "1.0",
  "name": "Buntes Theme",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/bg-040-0df8e190c15355cd3fa41a58e86426a9.svg"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgb(52, 255, 0)",
      "toolbar_text": "rgb(0, 0, 0)",
      "frame": "rgb(0, 0, 0)",
      "tab_background_text": "rgb(255, 0, 0)",
      "toolbar_field": "rgb(0, 0, 0)",
      "toolbar_field_text": "rgb(255, 0, 182)",
      "tab_line": "rgb(255, 145, 66)",
      "popup": "rgb(6, 6, 6)",
      "popup_text": "rgb(255, 162, 0)",
      "tab_loading": "rgb(255, 145, 66)"
    }
  }
}