Why does the site flash blue text when switching between pages?

Site URL: https://www.aconservationjournal.com/

When you switch from one page to another, there is a split second (or more if the internet connection is slow) where the text is blue. I am pretty sure this was the color in the template but it should be overridden by now. How can I fix this?

Try adding this to Home > Design > Custom CSS

body[data-menu-overlay-theme-switcher="true"]:not(.header--menu-open) .black .header-title-text a {
    color: white !important;
}