Gray color scheme for https://github.com/izhangzhihao/intellij-rainbow-brackets

rainbow_brackets.xml

<application>
  <component name="RainbowSettings">
    <option name="rainbowifyHTMLInsideJS" value="true" />
    <option name="version" value="5.1" />
    <option name="lightRoundBracketsColors">
      <array>
        <option value="0x263238" />
        <option value="0x455a64" />
        <option value="0x607d8b" />
        <option value="0x90a4ae" />
        <option value="0xcfd8dc" />
      </array>
    </option>
    <option name="lightSquareBracketsColors">
      <array>
        <option value="0x263238" />
        <option value="0x607d8b" />
        <option value="0xcfd8dc" />
      </array>
    </option>
    <option name="lightSquigglyBracketsColors">
      <array>
        <option value="0x263238" />
        <option value="0x607d8b" />
        <option value="0xcfd8dc" />
      </array>
    </option>
    <option name="darkRoundBracketsColors">
      <array>
        <option value="0x4f5b62" />
        <option value="0x718792" />
        <option value="0x8eacbb" />
        <option value="0xc1d5e0" />
        <option value="0xfefefe" />
      </array>
    </option>
    <option name="darkSquareBracketsColors">
      <array>
        <option value="0x4f5b62" />
        <option value="0x8eacbb" />
        <option value="0xfefefe" />
      </array>
    </option>
    <option name="darkSquigglyBracketsColors">
      <array>
        <option value="0x4f5b62" />
        <option value="0x8eacbb" />
        <option value="0xfefefe" />
      </array>
    </option>
  </component>
</application>

using Material Design Color Tool with Blue Grey color palette.