Daylight saving time makes it get dark later in the evening.
Tips
culture
Mainland China does not observe DST today - it was tried 1986-1991 and then abandoned. The whole country runs on a single time zone (北京时间, Beijing time), so 夏令时 mostly comes up when discussing the US, Europe, or scheduling international meetings.
memory
Literally 'summer-order time' - 夏令 means 'summer season/regulations' (parallel to 冬令 winter season), and 时 = time. The clocks follow summer's rules.
