You have errors in less/css
You can run static content deploy with errors on to get more of an idea on what is wrong. However you will have to work through the errors fixing them as you seem them. Typically it's missing less variables.
php -d memory_limit=-1 -d display_errors=1 bin/magento setup:static-content:deploy
If you are really not sure what the ...
If you want to reflect the JS and CSS changes on the fly, you need to be set the mode to developer, the JS resources will be created as symlinks in the pub folder on the fly and the changes you made either to the ones in the pub folder or the original ones will update both of the files.
For the CSS resources, you will need to remove the compiled one in the ...
To Reflect the Changes just Remove that Deployed file in pub/static folder
Magento 2 will auto create the missing/deleted static files.
Created Command For Deleting this :-
rm -rf pub/static/frontend/ pub/static/adminhtml/
pub/static/_requirejs pub/static/deployed_version.txt var/cache
var/page_cache var/generation var/view_preprocessed var/...