Fix mobile display and animation added

HTML:
-deleted input tag with invisible checkbox needed for nav bar (works now
with jquery)
-set anchor tags for navigation buttons
-put event circles in easy editable div tag
-maps got an id now

CSS:
-deleted all styles for said input tag
-reduced size of search field to avoid overflow with nav bar at low
resolutions

JS:
-"inhalt" div and children change styles on resize, in particular on
mobile devices, now (hopefully) no overflows and good display
-found great jquery function (toggle) for "impressum" tabs, deleted
non-efficient code
-smooth scrolling animations
-nav bar toggling now works with jquery (earlier: CSS)