The <mspace> MathML element is used to display a blank space, whose size is set by its attributes.
This element's attributes include the global MathML attributes as well as the following attributes:
depthA <length-percentage> indicating the desired depth (below the baseline) of the space.
heightA <length-percentage> indicating the desired height (above the baseline) of the space.
widthA <length-percentage> indicating the desired width of the space.
Note: For the depth, height, width attributes, some browsers may also accept legacy MathML lengths.
<math display="block">
<mn>1</mn>
<mspace depth="40px" height="20px" width="100px" />
<mn>2</mn>
</math>mspace {
background: lightblue;
}