:root {
	--bg: #f2f2f7;
	--card: #ffffff;
	--text: #000000;
	--muted: rgba(60, 60, 67, 0.65);
	--track: rgba(118, 118, 128, 0.14);
	--segment: #ffffff;
	--accent: #1a66a8;
	--accent-glow: #3fa9f5;
	--accent-text: #ffffff;
	--stop: #d93a30;
	--notice-bg: #fff3d6;
	--notice-text: #5c4300;
	--shadow: 0 1px 3px rgba(0, 0, 0, 0.12);
	color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
	:root {
		--bg: #000000;
		--card: #1c1c1e;
		--text: #ffffff;
		--muted: rgba(235, 235, 245, 0.6);
		--track: rgba(118, 118, 128, 0.32);
		--segment: #636366;
		--accent: #4a96dc;
		--accent-glow: #8fd0ff;
		--accent-text: #000000;
		--stop: #ff5a50;
		--notice-bg: #3a2f14;
		--notice-text: #ffd98a;
		--shadow: none;
	}
}

* {
	box-sizing: border-box;
}

[hidden] {
	display: none !important;
}

html {
	-webkit-text-size-adjust: 100%;
	-webkit-tap-highlight-color: transparent;
}

body {
	margin: 0;
	min-height: 100dvh;
	display: flex;
	flex-direction: column;
	background: var(--bg);
	color: var(--text);
	font: 17px/1.35 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
	touch-action: manipulation;
	-webkit-user-select: none;
	user-select: none;
	padding: env(safe-area-inset-top) env(safe-area-inset-right) 0 env(safe-area-inset-left);
}

form {
	width: 100%;
	max-width: 480px;
	margin: auto;
	padding: 16px;
	display: flex;
	flex-direction: column;
	gap: 16px;
}

.notice {
	display: flex;
	align-items: flex-start;
	gap: 8px;
	padding: 12px 8px 12px 16px;
	border-radius: 14px;
	background: var(--notice-bg);
	color: var(--notice-text);
	font-size: 15px;
}

.notice p {
	flex: 1;
	margin: 0;
	padding-top: 2px;
}

.notice button {
	flex: none;
	width: 32px;
	height: 32px;
	margin: -4px 0;
	border: 0;
	border-radius: 50%;
	background: transparent;
	color: inherit;
	font: inherit;
	font-size: 22px;
	line-height: 1;
	cursor: pointer;
}

.notice button:active {
	background: rgba(0, 0, 0, 0.08);
}

header {
	text-align: center;
}

header img {
	display: block;
	margin: 0 auto 4px;
}

h1 {
	margin: 0;
	font-size: 28px;
	font-weight: 700;
	letter-spacing: -0.01em;
}

header p,
.hint {
	margin: 6px 0 0;
	color: var(--muted);
	font-size: 15px;
}

fieldset {
	margin: 0;
	padding: 0;
	border: 0;
	min-width: 0;
}

.card {
	background: var(--card);
	border-radius: 14px;
	padding: 14px 16px 16px;
	box-shadow: var(--shadow);
}

legend {
	float: left;
	width: 100%;
	margin-bottom: 10px;
	padding: 0;
	color: var(--muted);
	font-size: 13px;
	font-weight: 600;
	text-transform: uppercase;
	letter-spacing: 0.04em;
}

legend + * {
	clear: both;
}

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

.sub {
	margin-top: 12px;
}

/* Locked controls dim, but readouts (like the live speed) stay bright. */
fieldset:disabled legend,
fieldset:disabled .stepper,
fieldset:disabled .segmented {
	opacity: 0.45;
}

/* ---------- Speed ---------- */

.readout {
	display: flex;
	align-items: baseline;
	justify-content: center;
	gap: 8px;
	margin-bottom: 8px;
}

.readout output {
	font-size: 56px;
	font-weight: 700;
	font-variant-numeric: tabular-nums;
	line-height: 1;
}

.readout span {
	color: var(--muted);
}

.stepper,
.slider-row {
	display: flex;
	align-items: center;
	gap: 12px;
}

.stepper button {
	flex: none;
	width: 44px;
	height: 44px;
	border: 0;
	border-radius: 50%;
	background: var(--track);
	color: var(--text);
	font: inherit;
	font-size: 24px;
	line-height: 1;
	cursor: pointer;
}

.stepper button:active {
	opacity: 0.6;
}

.slider-row + .slider-row {
	margin-top: 8px;
}

.slider-row > :first-child {
	flex: none;
	min-width: 3.2em;
}

.slider-row .segmented {
	flex: 1;
}

.slider-row output {
	flex: none;
	min-width: 4.5em;
	text-align: right;
	font-variant-numeric: tabular-nums;
}

/* ---------- Range inputs ---------- */

input[type="range"] {
	flex: 1;
	min-width: 0;
	height: 44px;
	margin: 0;
	background: transparent;
	accent-color: var(--accent);
	-webkit-appearance: none;
	appearance: none;
	/* A drag that starts on a slider belongs to the slider: without this,
	   Android Chrome can hand a slightly-downward drag to pull-to-refresh or
	   page scrolling mid-gesture, so the thumb stutters and stops following. */
	touch-action: none;
}

input[type="range"]::-webkit-slider-runnable-track {
	height: 4px;
	border-radius: 2px;
	background: linear-gradient(to right, var(--accent) var(--fill, 0%), var(--track) var(--fill, 0%));
}

input[type="range"]::-moz-range-track {
	height: 4px;
	border-radius: 2px;
	background: var(--track);
}

input[type="range"]::-moz-range-progress {
	height: 4px;
	border-radius: 2px;
	background: var(--accent);
}

input[type="range"]::-webkit-slider-thumb {
	-webkit-appearance: none;
	width: 28px;
	height: 28px;
	margin-top: -12px;
	border-radius: 50%;
	background: #ffffff;
	box-shadow: 0 0.5px 4px rgba(0, 0, 0, 0.3), 0 0 0 0.5px rgba(0, 0, 0, 0.06);
}

input[type="range"]::-moz-range-thumb {
	width: 28px;
	height: 28px;
	border: 0;
	border-radius: 50%;
	background: #ffffff;
	box-shadow: 0 0.5px 4px rgba(0, 0, 0, 0.3);
}

/* ---------- Segmented controls ---------- */

.segmented {
	display: grid;
	grid-auto-columns: 1fr;
	grid-auto-flow: column;
	gap: 2px;
	padding: 2px;
	border-radius: 9px;
	background: var(--track);
}

.segmented label {
	position: relative;
}

.segmented input {
	position: absolute;
	opacity: 0;
	inset: 0;
	margin: 0;
}

.segmented span {
	display: block;
	padding: 8px 4px;
	border-radius: 7px;
	text-align: center;
	font-size: 15px;
	font-weight: 500;
	white-space: nowrap;
	cursor: pointer;
}

.segmented input:checked + span {
	background: var(--segment);
	font-weight: 600;
	box-shadow: 0 2px 6px rgba(0, 0, 0, 0.12);
}

.segmented input:focus-visible + span {
	outline: 2px solid var(--accent);
	outline-offset: 1px;
}

/* ---------- Mode progress ---------- */

.progress {
	margin-top: 14px;
	padding-top: 14px;
	border-top: 0.5px solid var(--track);
}

.progress-head {
	display: flex;
	justify-content: space-between;
	align-items: baseline;
	gap: 12px;
	margin-bottom: 10px;
}

#progress-label {
	font-weight: 600;
}

#progress-time,
.progress-detail {
	color: var(--muted);
	font-size: 15px;
	font-variant-numeric: tabular-nums;
}

.progress-detail {
	margin-top: 8px;
}

.progress-track {
	display: flex;
	gap: 6px;
}

.progress-segment {
	position: relative;
	flex: 1;
	height: 10px;
	border-radius: 5px;
	background: var(--track);
}

.progress-segment > div {
	position: absolute;
	top: 0;
	bottom: 0;
	left: 0;
	width: calc(var(--p, 0) * 100%);
	border-radius: inherit;
	background: linear-gradient(90deg, var(--accent), var(--accent-glow));
	box-shadow: 0 0 10px color-mix(in srgb, var(--accent-glow) 55%, transparent);
	overflow: hidden;
}

.progress-segment.done > div {
	background: var(--accent);
	box-shadow: none;
}

/* A soft highlight drifting along the bar while it fills. */
.running .progress-segment:not(.done) > div::after {
	content: "";
	position: absolute;
	inset: 0;
	background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.45), transparent);
	transform: translateX(-100%);
	animation: shimmer 2.4s ease-in-out infinite;
}

@keyframes shimmer {
	to {
		transform: translateX(100%);
	}
}

@media (prefers-reduced-motion: reduce) {
	.running .progress-segment > div::after {
		animation: none;
		display: none;
	}
}

/* ---------- Play ---------- */

.dock {
	position: sticky;
	bottom: 0;
	padding: 12px 16px calc(12px + env(safe-area-inset-bottom));
	background: linear-gradient(transparent, var(--bg) 30%);
}

#play {
	display: block;
	width: 100%;
	max-width: 448px;
	height: 56px;
	margin: 0 auto;
	border: 0;
	border-radius: 14px;
	background: var(--accent);
	color: var(--accent-text);
	font: inherit;
	font-size: 19px;
	font-weight: 600;
	cursor: pointer;
}

#play[aria-pressed="true"] {
	background: var(--stop);
}

#play:active {
	opacity: 0.8;
}

/* ---------- Toast ---------- */

#toast {
	position: fixed;
	left: 50%;
	top: calc(12px + env(safe-area-inset-top));
	width: max-content;
	max-width: calc(100% - 32px);
	padding: 12px 16px;
	border-radius: 12px;
	background: rgba(40, 40, 44, 0.88);
	-webkit-backdrop-filter: blur(20px) saturate(1.6);
	backdrop-filter: blur(20px) saturate(1.6);
	color: #ffffff;
	font-size: 15px;
	text-align: center;
	opacity: 0;
	transform: translate(-50%, -8px);
	transition: opacity 0.2s, transform 0.2s;
	pointer-events: none;
}

#toast.show {
	opacity: 1;
	transform: translate(-50%, 0);
}