问了前端事儿，我看过网页上加载，请求，顶部有个颜色进度条，这个是什么 JS

[loading]

nprogess

可配合 pjax

[jsonline]

JS 只有一种好么。这叫 Laser Loader
http://masterblogster.com/progress-bar-to-wordpress-website/

[ihacku]

https://github.com/rstacruz/nprogress

[paloalto]

符合楼主要求的：
https://github.com/rstacruz/nprogress
https://github.com/peachananr/loading-bar
https://github.com/HubSpot/pace

附送其他：
https://github.com/Gaya/QueryLoader2
https://github.com/codrops/PageLoadingEffects
https://github.com/codrops/CircularProgressButton/
https://github.com/codrops/ProgressButtonStyles/

[Tinple]

推荐一个，nanobar

https://github.com/jacoborus/nanobar