background color in the world in Fortress/Citadel

edit

So, I've been trying to put color in this circle.

I wanted to test color.

So, I wrote a simple sdf

 <?xml version="1.0" ?>
<sdf version="1.9">
  <world name="smol_worl">

    <scene>
      <ambient>0.2 0.2 0.2 1.0</ambient>
      <background>1 1 1 1.0</background>
      <grid>true</grid>
      <origin_visual>false</origin_visual>
    </scene>

      <!-- 3D scene -->
      <plugin filename="GzScene3D" name="3D View">
        <ignition-gui>
          <title>3D View</title>
          <property type="bool" key="showTitleBar">false</property>
          <property type="string" key="state">docked</property>
        </ignition-gui>

        <engine>ogre2</engine>
        <scene>scene</scene>
        <ambient_light>0.4 0.4 0.4</ambient_light>
        <background_color>0.18 0.85 0.07 0.8</background_color>
        <camera_pose>-6 0 6 0 0.5 0</camera_pose>
      </plugin>


      </world>
</sdf>

I learned that So, I changed the color. I wanted to test on neon green which is rgba(46, 218, 22, 0.8)

So obviously, background_color is between 0 to 1 so I divide each value by 255

which is <background_color>0.18 0.85 0.07 0.8</background_color>

the color of background is same as the screenshot.

I changed <background> inside the <scene> as well too.

The color is remain same. What did I miss?

Also could this be because of this?