Markup
<button tabindex="0" class="odyssey-date-select odyssey-date-select--month">
<div class="odyssey-date-select__icon"></div>
<span>January, 2020</span>
<span class="odyssey-date-select__middle-dash"> vs. </span>
<span>January, 2020</span>
</button>
Source:
src/components/datepicker.less, line 751