Embeddable world clock widget
Live, colour-coded time strips for the cities you choose. Free, no ads, no tracking inside the widget; it links back to datetime.world and that's the whole deal.
How it works
The widget is a lightweight page from datetime.world loaded in an iframe, so it can't touch your site and your site can't break it. It ticks live by default (visitors can drag the strips to scrub), or you can pin it to one moment, which is handy on event pages. Colours show each city's day: night, sunrise, working hours, evening. Time zone and daylight-saving data comes from the visitor's own browser, so it never goes stale.
Want the full planner instead? Open datetime.world.