Revert "Revert "HACK-587: smooth header transition on home page""

This reverts commit ee89d09c3859e1ef3bc9dfc5dd06d357747ff6b2.
Revert "Revert "HACK-587: make transition header for b-pages as well""

This reverts commit f5060b63164140cfc306a1dea714d3300f6aea59.
Revert "Revert "HACK-587: add header transition to other b-pages and mobile, remove old code""

This reverts commit 7df3e03ff3030d8eb5feba623b4b10baafd75ea2.
Revert "Revert "HACK-587: fix headers on tablet and adjust on mobile""

This reverts commit fd6feca573e66287158989a686d38f54bf0c47da.
Revert "Revert "HACK-587: stop the header from disappearing when changing tablet orientation, keep mobile header consistent""

This reverts commit c98c35873ad90d931f770553df72afa2e622d2fa.