Local CCTV please
If you are referring to the folding effect of the navigation bar
navbar-header There needs to be a button in this div, specifying the style of the red box, which represents the compressed button
At the same time, there is a div with the style of collapse, etc. Wait, it contains the content to be placed in the drop-down box
You can look for a few bootstrap example websites
For example: https://www.linode.com/?r=189b832fa284b138b38ba3a25094f6f3b4b4488d
Are the addresses referenced by link and script correct? Should it be http://