The last column of the first row is wrapped to the next line when viewing in Safari, and some other iOS based browsers.
Safari:
I know the issue is quite old, but I ran into this issue today, and wasted over 12 hours in fixing it. Though about 10 hours out of that were spent in realizing that safari is failing with 12-column bootstrap grid, and it is no other issue.
Fix that I made is rather simple. Here is the version for Visual Composer. Class names may vary for other frameworks.
.vc_row-flex:before, .vc_row-flex:after{
width: 0;
}