Template:Bar box/sandbox/styles.css

.bar-box-container-box {
	background: var(--background-color-neutral-subtle, #f8f9fa); 
	color: var(--color-base, #202122);
}

.bar-box-titlebar {
	background:var(--background-color-interactive-subtle, #f8f9fa); 
	color: var(--color-base, #202122);
}