Using solid borders (Safari is OK)

overriding with 0px (original problem)
border-color:black; border-style:solid;
border-width:0px 0px 2px 0px
overriding one border-width
border:2px solid black;
border-top-width:0px
setting only one side : border-bottom:2px solid black
overriding via border-style
border-color:black; border-width:2px;
border-style:none none solid none
showing that non-zero widths do override
border-color:black; border-style:solid;
border-width:2px 2px 6px 2px
showing that it's only an override problem
border-bottom:0px solid black

Using dotted borders (Safari Bug)

overriding with 0px (original problem)
border-color:black; border-style:dotted;
border-width:0px 0px 2px 0px
overriding one border-width
border:2px dotted black;
border-top-width:0px
setting only one side : border-bottom:2px dotted black
overriding via border-style
border-color:black; border-width:2px;
border-style:none none dotted none
showing that non-zero widths do override
border-color:black; border-style:dotted;
border-width:2px 2px 6px 2px
showing that it's only an override problem
border-bottom:0px dotted black

Using dashed borders (Safari Bug)

overriding with 0px (original problem)
border-color:black; border-style:dashed;
border-width:0px 0px 2px 0px
overriding one border-width
border:2px dashed black;
border-top-width:0px
setting only one side : border-bottom:2px dashed black
overriding via border-style
border-color:black; border-width:2px;
border-style:none none dashed none
showing that non-zero widths do override
border-color:black; border-style:dashed;
border-width:2px 2px 6px 2px
showing that it's only an override problem
border-bottom:0px dashed black

Using double borders (Safari is OK)

overriding with 0px (original problem)
border-color:black; border-style:double;
border-width:0px 0px 3px 0px
overriding one border-width
border:3px double black;
border-top-width:0px
setting only one side : border-bottom:3px double black
overriding via border-style
border-color:black; border-width:3px;
border-style:none none double none
showing that non-zero widths do override
border-color:black; border-style:double;
border-width:3px 3px 6px 3px
showing that it's only an override problem
border-bottom:0px double black

Using groove borders (Safari treats as solid, which is allowed)

overriding with 0px (original problem)
border-color:#99aacc; border-style:groove;
border-width:0px 0px 3px 0px
overriding one border-width
border:3px groove #99aacc;
border-top-width:0px
setting only one side : border-bottom:3px groove #99aacc
overriding via border-style
border-color:#99aacc; border-width:3px;
border-style:none none groove none
showing that non-zero widths do override
border-color:#99aacc; border-style:groove;
border-width:3px 3px 6px 3px
showing that it's only an override problem
border-bottom:0px groove #99aacc

Using ridge borders (Safari treats as solid, which is allowed)

overriding with 0px (original problem)
border-color:#99aacc; border-style:ridge;
border-width:0px 0px 3px 0px
overriding one border-width
border:3px ridge #99aacc;
border-top-width:0px
setting only one side : border-bottom:3px ridge #99aacc
overriding via border-style
border-color:#99aacc; border-width:3px;
border-style:none none ridge none
showing that non-zero widths do override
border-color:#99aacc; border-style:ridge;
border-width:3px 3px 6px 3px
showing that it's only an override problem
border-bottom:0px ridge #99aacc

Using inset borders (Safari treats as solid, which is allowed)

overriding with 0px (original problem)
border-color:#99aacc; border-style:inset;
border-width:0px 0px 3px 0px
overriding one border-width
border:3px inset #99aacc;
border-top-width:0px
setting only one side : border-bottom:3px inset #99aacc
overriding via border-style
border-color:#99aacc; border-width:3px;
border-style:none none inset none
showing that non-zero widths do override
border-color:#99aacc; border-style:inset;
border-width:3px 3px 6px 3px
showing that it's only an override problem
border-bottom:0px inset #99aacc

Using outset borders (Safari treats as solid, which is allowed)

overriding with 0px (original problem)
border-color:#99aacc; border-style:outset;
border-width:0px 0px 3px 0px
overriding one border-width
border:3px outset #99aacc;
border-top-width:0px
setting only one side : border-bottom:3px outset #99aacc
overriding via border-style
border-color:#99aacc; border-width:3px;
border-style:none none outset none
showing that non-zero widths do override
border-color:#99aacc; border-style:outset;
border-width:3px 3px 6px 3px
showing that it's only an override problem
border-bottom:0px outset #99aacc