id selector can be used to more elements. here is the example:
css:
#t_color{
color: red;
}
#f_style{
font-family: arial;
font-size: 20px;
}
html:
test only
the box text
I tested on internet explorer (ver. 11.0) and Chrome (ver.47.0). it works on both of them.
The "unique" only means one element can not have more than one id attributes like class selector. Neither
...
nor
...
