With the September 2021 release of ArcGIS Online, we added a new capability to Map Viewer called Effects. Effects bring Photoshop-like capabilities to your layers in your web maps. ArcGIS Online makes it very easy to try out simple visual effects that make your maps stand out and get noticed. For line symbols, the humble drop shadow often helps pop these linear patterns off the basemap, making them stand up and be noticed. In this example, you also see how to put a little bloom underneath and around the linear features to give a pleasant visual effect.
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