If you'd like to adjust the transparency of the tour listing background, reduce the opacity level (the .75) of the background-color class.
Just copy and paste this code right above the embedded widget.
<style>
.seated-events-table {
background-color: rgba(0,0,0,.75) !important;
</style>
Just reduce the .75 (to .5 or .2) if you want lighter transparency.
Example of .2 transparency.
Example of .5 transparency
