[css] Using CSS how to change only the 2nd column of a table

Try this:

.countTable table tr td:first-child + td

You could also reiterate in order to style the others columns:

.countTable table tr td:first-child + td + td {...} /* third column */
.countTable table tr td:first-child + td + td + td {...} /* fourth column */
.countTable table tr td:first-child + td + td + td +td {...} /* fifth column */