**Steps to reproduce:

1. Set the web browser to not maximized window but large enough to almost with the screen. 
2. Go to Monitoring -> Graphs 
3. Select a host with a graph.
4. Select a graph which fully fits in the current browser window with time selector expanded and no vertical scroll. (e.g. Zabbix preprocessing queue graph has only one element)
5. Resize the browser from top or bottom till vertical scroll appears. 

Result:

See that top menu correctly adapts to size change but the graph is now misaligned and horizontal scroll appears. 

Another scenario: Maximize the browser. Select a graph with many items which immediately does not fit in the browser view. Horizontal scroll and misalignment appears immediately. 

Same applies to the Latest data graphs and probably other locations I did not test. 

See screenshot...

Expected:
Graph area aligned together with the time selector at least in the maximized browser scenario. 

Tested on Chrome 67.0.3396.62 and IE11.