Add a Scrolling Marquee Announcement Bar

Add a scrolling marquee announcement bar to the top of my store. Include these rotating messages separated by a [SEPARATOR] symbol: [MESSAGE_1], [MESSAGE_2], [MESSAGE_3], [MESSAGE_4]. The text should scroll continuously from right to left at a [SCROLL_SPEED] speed (options: slow, medium, fast). Use [BACKGROUND_COLOR] for the bar background and [TEXT_COLOR] for the text at [FONT_SIZE] pixels. Set the bar height to [BAR_HEIGHT] pixels. The scroll should pause when a customer hovers over the bar. Each message can optionally link to a different URL. Make the messages repeat seamlessly so there is no visible gap. On mobile, use the same scrolling behavior but allow a slightly smaller font size.