trouble accessing a pseudo element

I have a bunch of elements formed this way:

[code=html]<p class=”T”>some text</p>[/code]

and some css:

[CODE].T:after { position:relative; visibility:hidden; content: ” more text.” }[/CODE]

Having trouble accessing “T:after” to change the visibility. Something like:

[CODE]
var elT = document.getElementsByClassName(“T”)

function changeT() {
for (i=0; i<elT.length; i++) {
if (elT.item(i).firstChild:after.style.visibility == “hidden”) {
elT.item(i).firstChild:after.style.visibility = “visible”) }
}
}
[/CODE]

Any suggestions?

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