社长 Apple Watch界面设计规范
苹果官方最新的设计规范：
https://developer.apple.com/design/human-interface-guidelines/watchos/overview/themes/
苹果官方最新UI模板下载：
watchOS 5 10.14 (Requires Sketch 51 or greater)
watchOS 5 (2.3 MB)
watchOS 5 (534 MB)
To download watchOS device frames for use when marketing your app, see App Store Marketing Guidelines.
