Examine source code of Dream Color Gradient

{
  "name": "Dream Color Gradient",
  "manifest_version": 2,
  "version": "2.0",
  "theme": {
    "images": {
      "theme_frame": "theme.png"
    },
    "colors": {
      "frame": "rgba(255, 255, 255, 0)",
      "tab_background_text": "rgba(52, 69, 99, 1)",
      "toolbar": "rgba(0, 0, 0, 0.11)",
      "toolbar_field": "rgba(52, 69, 99, 1)",
      "toolbar_field_text": "rgba(224, 163, 255, 0.7)",
      "tab_line": "rgba(0, 0, 0, 0.11)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{2c18ed59-561a-4eb3-a6c9-6bc4a48b6813}"
    }
  }
}