calendar-widget-grid-section-customizations.css

/** Change the background colour of the grid header area */
.tribe_mini_calendar_widget thead,
.tribe_mini_calendar_widget .tribe-mini-calendar-nav td {
	background: lightblue;
}

/** Change the colour scheme of the days of the week */
.tribe_mini_calendar_widget .tribe-mini-calendar-dayofweek {
	background: yellow;
	color: black;
}

/** Make highlighted days (those that have events) pop out a little more */
.tribe-mini-calendar td.tribe-events-has-events {
	background: #FAa060;
}

/** Remove the "dot icon" for populated days */
.tribe-mini-calendar .tribe-events-has-events div[id*="daynum-"] a::before {
	display: none;
}