<mujoco>
    <default class="main">
        <geom size="1 1 1" rgba="1 0 0 1" />
        <default class="sub">
            <geom rgba="0 1 0 1" />
        </default>
    </default>

    <worldbody>
        <geom type="box" />
        <body childclass="sub" name="body0">
            <geom type="ellipsoid"/>
            <geom type="sphere" rgba="0 0 1 0"/>
            <geom type="cylinder" class="main"/>
        </body>
    </worldbody>
</mujoco>
