NSString *jScript = @"var meta = document.createElement('meta'); meta.setAttribute('name', 'viewport'); meta.setAttribute('content', 'width=device-width'); document.getElementsByTagName('head')[0].appendChild(meta);";

WKUserScript *wkUScript = [[WKUserScript alloc] initWithSource:jScript
                                                 injectionTime:WKUserScriptInjectionTimeAtDocumentEnd
                                              forMainFrameOnly:YES];
WKUserContentController *wkUController = [[WKUserContentController alloc] init];
[wkUController addUserScript:wkUScript];

[webView eva luatejava script:@"document.getElementsByClassName('图片xxx')[0].style='width: 70px;height:auto !important;'" completionHandler:^(id _Nullable htmlStr, NSError * _Nullable error) {
}];

[webView eva luatejava script:@"document.body.removeChild(document.getElementsByClassName('xxx')[0])" completionHandler:^(id _Nullable htmlStr, NSError * _Nullable error) {
    }];

[webView eva luatejava script:@"document.body.getElementsByClassName('xxx1')[0].removeChild(document.getElementsByClassName('xxx1')[0].getElementsByClassName('xxx2')[0])" completionHandler:^(id _Nullable htmlStr, NSError * _Nullable error) {

}];