:root {
	color-scheme: dark;
	--base: #1c1a21;
	--panel: #27242d;
	--rule: #38333f;
	--text: #eee8de;
	--muted: #9a92a3;
	--led: hsl(170 90% 58%);
	--led-ink: #10201d;
	--danger: #ff8a7a;
	--radius-lg: 22px;
	--radius-sm: 12px;
	--ui: ui-rounded, "SF Pro Rounded", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
	--body: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

* { box-sizing: border-box; }

html, body {
	margin: 0;
	background: var(--base);
	color: var(--text);
	font: 16px/1.45 var(--body);
	-webkit-text-size-adjust: 100%;
	-webkit-tap-highlight-color: transparent;
}

body.showing { overflow: hidden; background: #000; }

button, input, textarea { font: inherit; color: inherit; }

:focus-visible { outline: 3px solid var(--led); outline-offset: 2px; }

.visually-hidden {
	position: absolute; width: 1px; height: 1px; overflow: hidden;
	clip-path: inset(50%); white-space: nowrap;
}

.editor {
	max-width: 34rem;
	margin: 0 auto;
	padding: max(12px, env(safe-area-inset-top)) max(16px, env(safe-area-inset-right)) calc(32px + env(safe-area-inset-bottom)) max(16px, env(safe-area-inset-left));
}

.topbar { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 4px 0 14px; }

h1 { font: 700 1.35rem/1.1 var(--ui); margin: 0; letter-spacing: -0.01em; white-space: nowrap; }

h2 { font: 650 1.05rem/1.2 var(--ui); margin: 0 0 12px; }

h3 { font: 650 1rem/1.2 var(--ui); margin: 24px 0 8px; }

.tools { display: flex; gap: 8px; }

.tool {
	border: 1px solid var(--rule);
	background: var(--panel);
	border-radius: 999px;
	padding: 8px 14px;
	font: 600 0.9rem/1 var(--ui);
	cursor: pointer;
}

.tool.icon { display: grid; place-items: center; width: 40px; height: 40px; padding: 0; }

.tool.install { background: var(--led); color: var(--led-ink); border-color: transparent; white-space: nowrap; font-size: 0.85rem; }

/* The preview is the sign itself, rendered by the same WASM core. */
.preview {
	display: grid;
	place-items: center;
	width: 100%;
	aspect-ratio: 16 / 5;
	padding: 0;
	border: 0;
	border-radius: var(--radius-lg);
	background: #000;
	overflow: hidden;
	cursor: pointer;
	box-shadow: 0 0 0 1px var(--rule), 0 18px 40px -24px var(--led);
}

.preview canvas, .display canvas { display: block; image-rendering: pixelated; }

.compose { margin: 16px 0 24px; }

textarea {
	width: 100%;
	resize: vertical;
	min-height: 3.2em;
	padding: 14px 16px;
	border-radius: var(--radius-sm);
	border: 1px solid var(--rule);
	background: var(--panel);
	font: 600 1.15rem/1.35 var(--ui);
}

textarea::placeholder { color: var(--muted); }

.compose-actions { display: flex; gap: 8px; margin-top: 10px; }

.primary, .secondary {
	border-radius: 999px;
	padding: 12px 20px;
	font: 650 1rem/1 var(--ui);
	cursor: pointer;
	border: 1px solid transparent;
}

.primary { background: var(--led); color: var(--led-ink); }

.primary:disabled { opacity: 0.4; cursor: not-allowed; }

.secondary { background: transparent; border-color: var(--rule); }

#show { flex: 1; font-size: 1.1rem; }

.wide { width: 100%; }

.error { color: var(--danger); margin: 8px 0 0; }

.note { color: var(--muted); font-size: 0.9rem; margin: 10px 0 0; }

.group { border-top: 1px solid var(--rule); padding: 20px 0 22px; }

.slider { display: block; margin: 0 0 16px; }

.slider span { display: flex; justify-content: space-between; color: var(--muted); font-size: 0.9rem; margin-bottom: 6px; }

input[type="range"] {
	-webkit-appearance: none;
	appearance: none;
	width: 100%;
	height: 32px;
	background: transparent;
	--track: linear-gradient(90deg, var(--rule), var(--led));
}

.hue input { --track: linear-gradient(90deg, hsl(0 90% 58%), hsl(60 90% 58%), hsl(120 90% 58%), hsl(180 90% 58%), hsl(240 90% 58%), hsl(300 90% 58%), hsl(360 90% 58%)); }

.intensity input { --track: linear-gradient(90deg, #fff, var(--led)); }

input[type="range"]::-webkit-slider-runnable-track { height: 8px; border-radius: 8px; background: var(--track); }

input[type="range"]::-moz-range-track { height: 8px; border-radius: 8px; background: var(--track); }

input[type="range"]::-webkit-slider-thumb {
	-webkit-appearance: none;
	width: 30px; height: 30px; margin-top: -11px;
	border-radius: 50%; background: var(--text); border: 0;
	box-shadow: 0 2px 8px rgb(0 0 0 / 0.5);
}

input[type="range"]::-moz-range-thumb { width: 30px; height: 30px; border-radius: 50%; background: var(--text); border: 0; }

fieldset { border: 0; padding: 0; margin: 0 0 16px; }

legend { color: var(--muted); font-size: 0.9rem; margin-bottom: 8px; padding: 0; }

.choices { display: flex; flex-wrap: wrap; gap: 8px; }

.choices input { position: absolute; opacity: 0; pointer-events: none; }

.choices span {
	display: inline-flex; align-items: center; gap: 8px;
	padding: 10px 14px;
	border-radius: var(--radius-sm);
	border: 1px solid var(--rule);
	background: var(--panel);
	cursor: pointer;
}

.choices input:checked + span { border-color: var(--led); box-shadow: inset 0 0 0 1px var(--led); }

.choices input:focus-visible + span { outline: 3px solid var(--led); outline-offset: 2px; }

.f-mono { font-family: "Berkeley Mono", ui-monospace, "SF Mono", Menlo, monospace; }
.f-sans { font-family: system-ui, sans-serif; }
.f-serif { font-family: ui-serif, "New York", Georgia, serif; }
.f-bold { font-family: system-ui, sans-serif; font-weight: 900; }
.f-rounded { font-family: ui-rounded, "SF Pro Rounded", system-ui, sans-serif; font-weight: 700; }

.dot { display: inline-block; width: 14px; height: 14px; background: var(--led); }
.dot.round { border-radius: 50%; }

.switches { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; }

.switches.stacked { grid-template-columns: 1fr; }

.switch {
	display: flex; align-items: center; gap: 12px;
	padding: 12px 14px;
	border-radius: var(--radius-sm);
	background: var(--panel);
	cursor: pointer;
}

.switch small { display: block; color: var(--muted); font-size: 0.85rem; margin-top: 2px; }

.switch input {
	-webkit-appearance: none;
	appearance: none;
	flex: none;
	width: 46px; height: 28px; margin: 0;
	border-radius: 999px;
	background: var(--rule);
	position: relative;
	cursor: pointer;
	transition: background 120ms;
}

.switch input::after {
	content: "";
	position: absolute; top: 3px; left: 3px;
	width: 22px; height: 22px; border-radius: 50%;
	background: var(--text);
	transition: transform 120ms;
}

.switch input:checked { background: var(--led); }

.switch input:checked::after { transform: translateX(18px); }

.saved { list-style: none; margin: 0; padding: 0; }

.saved li { display: flex; align-items: center; gap: 8px; border-bottom: 1px solid var(--rule); padding: 6px 0; }

.saved .use { flex: 1; min-width: 0; text-align: left; background: none; border: 0; padding: 10px 0; font: 600 1rem/1.3 var(--ui); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; cursor: pointer; }

.saved .remove, .saved .keep, .text-button { background: none; border: 0; color: var(--muted); padding: 10px; font: inherit; cursor: pointer; }

.saved .keep:disabled { cursor: default; opacity: 0.6; }

.group-head { display: flex; align-items: baseline; justify-content: space-between; gap: 8px; }

.group-head .text-button { margin: -10px -10px 0 0; }

/* Display mode: a page-filling black stage, used directly as the fallback
   when the Fullscreen API is unavailable (iPhone Safari). */
.display {
	position: fixed;
	inset: 0;
	display: grid;
	place-items: center;
	background: #000;
	z-index: 10;
	overflow: hidden;
	touch-action: none;
	user-select: none;
	-webkit-user-select: none;
}

.display[hidden] { display: none; }

.display.safe { padding: env(safe-area-inset-top) env(safe-area-inset-right) env(safe-area-inset-bottom) env(safe-area-inset-left); }

.display canvas { position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%); }

.display canvas.rotated { transform: translate(-50%, -50%) rotate(90deg); }

.display-controls {
	position: absolute;
	bottom: max(16px, env(safe-area-inset-bottom));
	left: 50%;
	transform: translateX(-50%);
	display: grid;
	justify-items: center;
	gap: 10px;
	width: min(30rem, calc(100% - 32px));
	opacity: 0;
	pointer-events: none;
	transition: opacity 160ms;
}

.display-controls.visible { opacity: 1; pointer-events: auto; }

.display-buttons { display: flex; gap: 10px; }

.display-controls button {
	border: 1px solid rgb(255 255 255 / 0.25);
	background: rgb(30 28 34 / 0.85);
	color: #fff;
	border-radius: 999px;
	padding: 12px 22px;
	font: 650 1rem/1 var(--ui);
	cursor: pointer;
}

.display-note { margin: 0; padding: 8px 14px; border-radius: var(--radius-sm); background: rgb(30 28 34 / 0.85); color: var(--text); font-size: 0.9rem; text-align: center; }

.display-note:empty { display: none; }

.sheet {
	width: min(34rem, 100%);
	max-height: 88dvh;
	margin: auto auto 0;
	padding: 0 20px calc(24px + env(safe-area-inset-bottom));
	border: 0;
	border-radius: var(--radius-lg) var(--radius-lg) 0 0;
	background: var(--base);
	color: var(--text);
	overflow-y: auto;
}

.sheet::backdrop { background: rgb(0 0 0 / 0.55); }

.sheet-head { position: sticky; top: 0; display: flex; align-items: center; justify-content: space-between; padding: 18px 0 14px; background: var(--base); }

.sheet-head h2 { margin: 0; }

.sheet-head .primary { padding: 9px 16px; }

.steps { padding-left: 1.4em; }

.steps li { margin: 0 0 10px; }

.limits dt { font-weight: 650; margin-top: 12px; }

.limits dd { margin: 2px 0 0; color: var(--muted); font-size: 0.92rem; }

@media (min-width: 40rem) {
	.editor { padding-top: 32px; }
	.sheet { margin: auto; border-radius: var(--radius-lg); }
}

@media (prefers-reduced-motion: reduce) {
	* { transition: none !important; }
}