Use the Map Options to control the color scheme of selected map items.
With an application open to the Trip page, access the Tools pane then choose Map Options from the drop-down.
Expand the tree structure to find the desired map element then click on the swatch to open the presentation options dialog.
Click on the color swatch to open a color palette.
Transparency is presented in percentages. In the example, .60 equals 60%, meaning that 40% of the background image is showing through.
The Width is measured in pixels.
Click OK to execute your changes.