_core/engine/foot.engine.php 내 숨김 iframe에  hidden class 추가
Revert "_core/engine/foot.engine.php 내 숨김 iframe에  hidden class 추가"

This reverts commit 99d2c5af0d73f0506ba7a9063c994cc78d21a1dc.
_core/engine/foot.engine.php 내 iframe에 hidden class 추가함