Examine source code of It is the ocean.

{
  "theme": {
    "images": {
      "theme_frame": "d720--kaimenn--dsy100.jpg"
    },
    "colors": {
      "frame": "#beb9eb",
      "tab_background_text": "#000000"
    }
  },
  "version": "2.0",
  "name": "It is the ocean.",
  "manifest_version": 2,
  "description": "～大海原です。～\nd720--kaimenn--dsy100"
}