Add Bootstrap Toast as Alert on SharePoint site

[Chamonix]

It will be nice to have a Bootstrap v5.0 Toast as push notification to SharePoint site so to broadcast important message to users. 

I tried to put the reference to Bootstrap css and js file in Content editor web part, also tried with content link to a txt file that with toast code and reference to css & js file. However,  either way the web page messed up very bad. 

Pls advise if a solution is available?

[#2]

SharePoint on-prem or Online ?

[#3]

Sharepoint Online..

The Microsoft default CSS got messed up after I called Bootstrap CSS. If just Bootstrap JS, no issue. But without css, Toast doesn't have the expected look

[#4]

Okey, sounds like you're implementing this abit backward. You can not use Content editor web part to apply Bootstrap in Modern SharePoint. you will get alot of issues as said.

If you want to use Bootstrap toast you need to develop a Application Customizers Extension webpart using SPFX and do it from there, there it will be contained:

https://learn.microsoft.com/en-us/sharepoint/dev/spfx/extensions/overview-extensions