<!DOCTYPE HTML>
<style>
.aligntest {
    line-height: 16px;
    vertical-align: calc(25% + 5px);
}
</style>
<hr/>
<span class="aligntest">The first four words</span> in this sentence should have a line-height of 16px; they are also (25%+5px)-aligned, which should raise them 9px relative to the natural baseline.
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