style.css

/* Purple Light scheme (Default) */
/* Can be forced with data-theme="light" */
[data-theme="light"],
:root:not([data-theme="dark"]) {
	--primary: #8e24aa;
	--primary-hover: #7b1fa2;
	--primary-focus: rgba(142, 36, 170, 0.125);
	--primary-inverse: #FFF;
}

/* Purple Dark scheme (Auto) */
/* Automatically enabled if user has Dark mode enabled */
@media only screen and (prefers-color-scheme: dark) {
	:root:not([data-theme="light"]) {
		--primary: #8e24aa;
		--primary-hover: #9c27b0;
		--primary-focus: rgba(142, 36, 170, 0.25);
		--primary-inverse: #FFF;
	}
}

/* Purple Dark scheme (Forced) */
/* Enabled if forced with data-theme="dark" */
[data-theme="dark"] {
	--primary: #8e24aa;
	--primary-hover: #9c27b0;
	--primary-focus: rgba(142, 36, 170, 0.25);
	--primary-inverse: #FFF;
}

/* Purple (Common styles) */
:root {
	--form-element-active-border-color: var(--primary);
	--form-element-focus-color: var(--primary-focus);
	--switch-color: var(--primary-inverse);
	--switch-checked-background-color: var(--primary);
}

/* Custom styles */

.card-selected {
	outline-style: solid;
	outline-color: var(--primary);
	outline-width: .15em;
}

article {
	transition-property: outline-width, outline-color;
	transition-duration: 100ms;
	outline-style: solid;
	outline-color: var(--primary-hover);
	outline-width: 0em;
}

article:hover {
	outline-width: .15em;
}