the packaged webpack code works fine in the chorme test. But in ie and Firefox will inexplicably appear and chorme behavior. There is a problem when I set an element to opacity:0;transition:all 1s; then a trigger behavior becomes opacity:1;ie and Firefox: these elements with the transition attribute set will appear first (set not to occur unless the trigger event) as if they had gone through the transition first. But! At first I thought it was a problem with scss compiling css. Then I saw that the code was right, and then I took out all the code, packed it without webpack, and ran straight away. In that case, there will be no problem. I really don"t think there"s something wrong with it. Because the css code is the same. The js code is the same except for the code I used to import the picture with webpack. Paste the code below. 
if you need more detailed information, please leave a message, I would appreciate it!