:root {
	--font-ui: system-ui, Helvetica Neue, Helvetica, Segoe UI, sans-serif;
}

body {
	font: 120%/1.5 var(--font-ui);
	width: 90vw;
	max-width: 60em;
	margin: 1em auto;
	padding: 0 2em;
	transition: background .2s ease, color .2s ease;
}

body.bg-black {
	background: black;
	color: white;
}

h1 {
	text-align: center;
}

.intro {
	max-width: 42em;
	margin: 0 auto 2em;
	text-align: center;
	opacity: .8;
}

.inputs {
	display: flex;
	flex-wrap: wrap;
	align-items: center;
	justify-content: center;
	gap: 1.5em;
	margin-bottom: 2em;
}

.inputs label {
	display: flex;
	align-items: center;
	gap: .5em;
}

.inputs input[type="text"] {
	font: inherit;
	font-size: 100%;
	padding: .3em .6em;
	border: 3px solid var(--color, silver);
	border-radius: .3em;
	background: hsl(0 0% 100% / .8);
	color: black;
}

.inputs input:invalid {
	border-color: hsl(0 90% 45%);
}

.bg-toggle {
	cursor: pointer;
}

.stage {
	display: grid;
	gap: 2em;
	padding: 2em;
	border-radius: .5em;
}

figure {
	margin: 0;
}

figcaption {
	font-weight: bold;
	margin-bottom: .5em;
}

.gradient {
	height: 4em;
	border-radius: .3em;
	box-shadow: 0 0 0 1px hsl(0 0% 50% / .3);
}