Announcement Bar background color

Store Design
,
2

If it is not an option in the customiser you need to add this to your css file:

.header__tape {
  background-color: red; /* change to your desired color */
}
.header__tape p,
.header__tape i{
  color: white;
}

.header__tape p{
  font-size: 15px /* change to desired font size */
}