Please follow the instruction below, to add background colour to the event tag.
1) Please don’t forget to take a backup of the file prior to any change.
2) Open wp-content -> themes -> Tyler ->css -> layout.css via FTP or Cpanel
3) Add the following style at the end of the page:
.landing h1 span {background-color:#fff;} /* You can change this #fff colour */
4) Update the file.