Android Studio 3.0 cannot resolve symbol Theme

Question

As stated in style.xml, there is a weird error, which shows Cannot resolve symbol \'Theme\', which is quite strange.

See pic of the error :-

My Project Spe

Answer 1

Delete 'com.android.support:appcompat-v7:27.0.0','com.android.support:design:27.0.0' compile from app build.gradle then sync and then again paste those 2 compile then sync.... it will solve