Examine source code of pinktheme :-)

{
  "manifest_version": 2,
  "version": "1.0",
  "name": ":-)",
  "theme": {
    "images": {
      "additional_backgrounds": [
        "images/0.png"
      ]
    },
    "properties": {
      "additional_backgrounds_alignment": [
        "right top"
      ],
      "additional_backgrounds_tiling": [
        "repeat"
      ]
    },
    "colors": {
      "toolbar": "rgba(246, 146, 203, 0.43)",
      "toolbar_text": "rgb(255, 206, 213)",
      "frame": "rgb(47, 46, 47)",
      "tab_background_text": "rgb(255, 0, 153)",
      "toolbar_field": "rgba(125, 236, 193, 0.67)",
      "toolbar_field_text": "rgb(255, 255, 255)",
      "tab_line": "rgb(248, 112, 140)",
      "popup": "rgba(162, 250, 224, 0.38)",
      "popup_text": "rgb(202, 11, 120)",
      "button_background_active": "rgba(60, 192, 120, 0.97)",
      "button_background_hover": "rgba(20, 222, 163, 0.38)",
      "icons_attention": "rgba(51, 185, 146, 0.38)",
      "icons": "rgb(255, 202, 252)",
      "ntp_background": "rgba(243, 121, 159, 0.25)",
      "ntp_text": "rgb(17, 1, 16)",
      "popup_border": "rgba(15, 1, 5, 0.99)",
      "popup_highlight_text": "rgb(234, 35, 223)",
      "popup_highlight": "rgb(209, 201, 245)",
      "sidebar_border": "rgba(157, 0, 157, 0.38)",
      "tab_background_separator": "rgba(238, 138, 196, 0.32)",
      "tab_loading": "rgba(237, 248, 242, 0.97)",
      "tab_selected": "rgba(255, 92, 187, 0.32)",
      "tab_text": "rgb(125, 236, 193)",
      "toolbar_bottom_separator": "rgba(224, 22, 139, 0.32)",
      "toolbar_field_border_focus": "rgb(182, 6, 198)",
      "toolbar_field_border": "rgba(255, 255, 255, 0.99)",
      "toolbar_field_focus": "rgba(125, 236, 193, 0.3)",
      "toolbar_field_highlight_text": "rgba(248, 8, 248, 0.97)",
      "toolbar_field_highlight": "rgba(62, 61, 62, 0.97)",
      "toolbar_field_separator": "rgba(191, 27, 125, 0.99)",
      "toolbar_field_text_focus": "rgba(252, 10, 252, 0.97)",
      "toolbar_top_separator": "rgba(21, 1, 13, 0.99)",
      "toolbar_vertical_separator": "rgba(253, 0, 0, 0.99)"
    }
  }
}