Please see testcase. Safari seems to round the width value down when using desimals, e.g. 0.5% becomes 0. This is an extremely annoying bug which makes it hard to develop websites without tables, because it is a never a good idea to mix % and px values and always using 1%, 2%, 3% etc. as margin makes thing look buggy.
*** This bug has been marked as a duplicate of 5164 ***