/**
 * Kids Math Game — game UI stylesheet
 *
 * Loaded ONLY on the game page. Shared content styles (guides, About,
 * Privacy, FAQ lists and ad slots) live in site.css so article and guide
 * pages never load this file.
 *
 * Kid-friendly, high-contrast, fully responsive and touch-first.
 * Uses the "big button" pattern: every tappable control is at least
 * 56-64px tall with visible borders, so it works on tablets and phones.
 *
 * Accessibility notes:
 *  - Text colours chosen for WCAG AA contrast on their backgrounds.
 *  - Interactive elements get a strong focus outline for keyboard users.
 *  - Motion is disabled for users who prefer reduced motion.
 *  - The game never uses autoplay media or popups.
 */

.kmg-app {
	--kmg-bg: #fdf6ec;
	--kmg-card: #ffffff;
	--kmg-ink: #1f2328;
	--kmg-muted: #4b5563;
	--kmg-primary: #2456b8;
	--kmg-primary-dark: #1b4390;
	--kmg-primary-ink: #ffffff;
	--kmg-accent: #e8862e;
	--kmg-accent-ink: #4a2500;
	--kmg-good-bg: #e5f6e9;
	--kmg-good-ink: #14532d;
	--kmg-good-border: #2e7d46;
	--kmg-bad-bg: #fdecea;
	--kmg-bad-ink: #7f1d1d;
	--kmg-bad-border: #b3261e;
	--kmg-key-bg: #ffffff;
	--kmg-key-border: #c6ccd6;
	--kmg-radius: 18px;
	--kmg-tap: 64px;
	box-sizing: border-box;
	width: 100%;
	max-width: 720px;
	margin: 0 auto;
	padding: 16px;
	background: var(--kmg-bg);
	border-radius: 24px;
	color: var(--kmg-ink);
	font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
	font-size: 18px;
	line-height: 1.45;
	-webkit-font-smoothing: antialiased;
}

.kmg-app *,
.kmg-app *::before,
.kmg-app *::after {
	box-sizing: inherit;
}

.kmg-app button {
	font: inherit;
	color: inherit;
	cursor: pointer;
	-webkit-tap-highlight-color: transparent;
	touch-action: manipulation;
}

.kmg-app [hidden] {
	display: none !important;
}

/* Strong, always-visible keyboard focus. */
.kmg-app :is(button, a, summary, input):focus-visible {
	outline: 3px solid var(--kmg-primary);
	outline-offset: 3px;
	border-radius: 8px;
}

/* ------------------------------------------------------------------ *
 * Screens
 * ------------------------------------------------------------------ */

.kmg-screen {
	background: var(--kmg-card);
	border: 1px solid #e5e0d5;
	border-radius: var(--kmg-radius);
	padding: 20px;
	box-shadow: 0 2px 8px rgba(31, 35, 40, 0.06);
}

.kmg-screen h2 {
	margin: 0 0 4px;
	font-size: 26px;
	line-height: 1.2;
}

.kmg-screen p.kmg-tagline {
	margin: 0 0 18px;
	color: var(--kmg-muted);
	font-size: 17px;
}

.kmg-muted {
	color: var(--kmg-muted);
	font-size: 15px;
}

/* ------------------------------------------------------------------ *
 * Start screen
 * ------------------------------------------------------------------ */

.kmg-mode-grid {
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
	gap: 10px;
	margin: 10px 0 18px;
}

.kmg-mode-btn {
	display: flex;
	flex-direction: column;
	align-items: center;
	gap: 2px;
	min-height: 84px;
	padding: 12px 8px;
	border: 2px solid var(--kmg-key-border);
	border-radius: 14px;
	background: var(--kmg-key-bg);
	font-weight: 700;
}

.kmg-mode-btn .kmg-mode-icon {
	font-size: 30px;
	line-height: 1;
}

.kmg-mode-btn[aria-pressed="true"],
.kmg-mode-btn.is-selected {
	border-color: var(--kmg-primary);
	background: #eef3fd;
	box-shadow: 0 0 0 2px var(--kmg-primary) inset;
}

/* Difficulty stars */
.kmg-option-row {
	margin: 0 0 16px;
}

.kmg-option-row .kmg-option-label {
	display: block;
	font-weight: 700;
	margin-bottom: 8px;
}

.kmg-pill-group {
	display: flex;
	flex-wrap: wrap;
	gap: 8px;
}

.kmg-pill {
	min-height: 52px;
	padding: 8px 16px;
	border: 2px solid var(--kmg-key-border);
	border-radius: 999px;
	background: var(--kmg-key-bg);
	font-weight: 700;
	font-size: 17px;
}

.kmg-pill[aria-pressed="true"],
.kmg-pill.is-selected {
	border-color: var(--kmg-primary);
	background: #eef3fd;
	color: var(--kmg-primary-dark);
}

.kmg-start-btn {
	display: block;
	width: 100%;
	min-height: var(--kmg-tap);
	border: 0;
	border-radius: 14px;
	background: var(--kmg-primary);
	color: var(--kmg-primary-ink);
	font-size: 24px;
	font-weight: 800;
	letter-spacing: 0.3px;
}

.kmg-start-btn:hover {
	background: var(--kmg-primary-dark);
}

.kmg-howto {
	margin: 14px 0 0;
	font-size: 16px;
	color: var(--kmg-muted);
}

/* Lifetime stats + badges strip */
.kmg-stats-strip {
	display: flex;
	flex-wrap: wrap;
	gap: 10px;
	margin-top: 16px;
}

.kmg-stat-chip {
	flex: 1 1 auto;
	text-align: center;
	background: #eef3fd;
	border: 1px solid #d7e1f5;
	border-radius: 12px;
	padding: 8px 10px;
	font-size: 15px;
}

.kmg-stat-chip strong {
	display: block;
	font-size: 22px;
	color: var(--kmg-primary-dark);
}

.kmg-badges-box {
	margin-top: 16px;
}

.kmg-badges-box h3 {
	margin: 0 0 8px;
	font-size: 18px;
}

.kmg-badges-grid {
	display: grid;
	grid-template-columns: repeat(auto-fill, minmax(90px, 1fr));
	gap: 8px;
}

.kmg-badge-card {
	border: 1px solid var(--kmg-key-border);
	border-radius: 12px;
	background: var(--kmg-key-bg);
	text-align: center;
	padding: 10px 6px;
	font-size: 14px;
}

.kmg-badge-card.is-earned {
	border-color: #e9b04a;
	background: #fff7e2;
}

.kmg-badge-card .kmg-badge-icon {
	display: block;
	font-size: 28px;
	line-height: 1.2;
	color: #8a8f98;
}

.kmg-badge-card.is-earned .kmg-badge-icon {
	color: #b57112;
}

.kmg-badge-card .kmg-badge-name {
	display: block;
	font-weight: 700;
	font-size: 13px;
	margin-top: 4px;
}

.kmg-badge-card .kmg-badge-hint {
	display: block;
	font-size: 12px;
	color: var(--kmg-muted);
	margin-top: 2px;
}

.kmg-badge-card.is-earned .kmg-badge-hint {
	color: #2e7d46;
	font-weight: 700;
}

/* Sound toggle */
.kmg-sound-row {
	display: flex;
	align-items: center;
	gap: 10px;
	margin-top: 14px;
}

/* ------------------------------------------------------------------ *
 * Game screen
 * ------------------------------------------------------------------ */

.kmg-game-header {
	display: flex;
	flex-wrap: wrap;
	align-items: center;
	gap: 10px 18px;
	margin-bottom: 8px;
	font-size: 16px;
	font-weight: 700;
}

.kmg-progress {
	flex: 1 1 100%;
}

.kmg-progress-text {
	margin-bottom: 4px;
}

.kmg-progress-track {
	height: 12px;
	border-radius: 999px;
	background: #e7e2d6;
	overflow: hidden;
}

.kmg-progress-fill {
	height: 100%;
	width: 0;
	border-radius: 999px;
	background: var(--kmg-primary);
	transition: width 0.35s ease;
}

.kmg-score-badge,
.kmg-streak-badge {
	background: #eef3fd;
	border-radius: 999px;
	padding: 6px 14px;
	font-size: 17px;
}

.kmg-streak-badge.is-hot {
	background: #fff0dc;
	color: var(--kmg-accent-ink);
}

/* Timer bar */
.kmg-timer {
	margin-bottom: 10px;
}

.kmg-timer-track {
	height: 14px;
	border-radius: 999px;
	background: #e7e2d6;
	overflow: hidden;
}

.kmg-timer-fill {
	height: 100%;
	width: 100%;
	background: var(--kmg-accent);
	transition: width 1s linear;
}

.kmg-timer-fill.is-low {
	background: var(--kmg-bad-border);
}

.kmg-timer-text {
	font-size: 14px;
	color: var(--kmg-muted);
	margin-top: 4px;
	text-align: right;
}

/* Problem */
.kmg-problem {
	text-align: center;
	padding: 10px 0 6px;
}

.kmg-problem-equation {
	font-size: clamp(44px, 12vw, 76px);
	font-weight: 800;
	letter-spacing: 2px;
	color: var(--kmg-ink);
}

/* Answer display */
.kmg-answer-display {
	min-height: 76px;
	display: flex;
	align-items: center;
	justify-content: center;
	margin: 6px 0 14px;
	background: #f7f2e7;
	border: 2px solid var(--kmg-key-border);
	border-radius: 14px;
	font-size: 42px;
	font-weight: 800;
	color: var(--kmg-ink);
	caret-color: transparent;
}

.kmg-answer-display::after {
	content: "";
	display: inline-block;
	width: 3px;
	height: 44px;
	background: var(--kmg-primary);
	margin-left: 4px;
	animation: kmg-blink 1s steps(2) infinite;
}

@keyframes kmg-blink {
	50% {
		opacity: 0;
	}
}

/* Keypad */
.kmg-keypad {
	display: grid;
	grid-template-columns: repeat(3, 1fr);
	gap: 10px;
	margin-bottom: 14px;
}

.kmg-key {
	min-height: var(--kmg-tap);
	border: 2px solid var(--kmg-key-border);
	border-radius: 14px;
	background: var(--kmg-key-bg);
	font-size: 28px;
	font-weight: 700;
}

.kmg-key:active {
	background: #eef1f6;
}

.kmg-key--backspace {
	font-size: 24px;
}

.kmg-key--check {
	background: #1f9d55;
	border-color: #1f9d55;
	color: #ffffff;
	font-size: 24px;
	font-weight: 800;
	grid-column: 1 / -1;
}

.kmg-key--check:hover {
	background: #177a42;
}

/* Feedback */
.kmg-feedback {
	min-height: 84px;
	margin-top: 4px;
	border-radius: 14px;
	padding: 14px 16px;
	font-size: 18px;
	font-weight: 700;
	text-align: center;
	transition: background 0.2s ease;
}

.kmg-feedback.is-good {
	background: var(--kmg-good-bg);
	color: var(--kmg-good-ink);
	border: 2px solid var(--kmg-good-border);
}

.kmg-feedback.is-bad {
	background: var(--kmg-bad-bg);
	color: var(--kmg-bad-ink);
	border: 2px solid var(--kmg-bad-border);
}

.kmg-feedback .kmg-feedback-title {
	display: block;
	font-size: 22px;
	margin-bottom: 2px;
}

.kmg-feedback .kmg-feedback-detail {
	font-weight: 500;
}

.kmg-feedback .kmg-feedback-hint {
	display: block;
	margin-top: 4px;
	font-weight: 400;
	font-size: 16px;
}

/* ------------------------------------------------------------------ *
 * Result screen
 * ------------------------------------------------------------------ */

.kmg-result-hero {
	text-align: center;
	padding: 10px 0 4px;
}

.kmg-result-hero .kmg-big-score {
	font-size: 72px;
	font-weight: 800;
	color: var(--kmg-primary-dark);
	line-height: 1.1;
}

.kmg-result-stats {
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
	gap: 10px;
	margin: 16px 0;
}

.kmg-result-stat {
	text-align: center;
	background: #f7f2e7;
	border-radius: 12px;
	padding: 12px 8px;
}

.kmg-result-stat strong {
	display: block;
	font-size: 26px;
	color: var(--kmg-primary-dark);
}

.kmg-result-stat span {
	font-size: 15px;
	color: var(--kmg-muted);
}

.kmg-new-badges {
	margin: 8px 0 16px;
	text-align: center;
	background: #fff7e2;
	border: 1px solid #e9b04a;
	border-radius: 14px;
	padding: 12px;
}

.kmg-new-badges h3 {
	margin: 0 0 8px;
	font-size: 20px;
	color: #8a5a0b;
}

.kmg-new-badges .kmg-badge-line {
	display: inline-block;
	margin: 4px;
	padding: 6px 12px;
	background: #ffffff;
	border: 1px solid #e9b04a;
	border-radius: 999px;
	font-weight: 700;
}

.kmg-actions {
	display: flex;
	flex-wrap: wrap;
	gap: 10px;
}

.kmg-action-btn {
	flex: 1 1 auto;
	min-height: 58px;
	padding: 8px 16px;
	border-radius: 12px;
	font-size: 19px;
	font-weight: 800;
	border: 2px solid var(--kmg-key-border);
	background: var(--kmg-key-bg);
}

.kmg-action-btn--primary {
	background: var(--kmg-primary);
	border-color: var(--kmg-primary);
	color: var(--kmg-primary-ink);
}

/* ------------------------------------------------------------------ *
 * Loading state
 * ------------------------------------------------------------------ */

.kmg-loading {
	text-align: center;
	color: var(--kmg-muted);
	padding: 40px 0;
}

@media (max-width: 480px) {
	.kmg-app {
		padding: 10px;
		border-radius: 16px;
		font-size: 17px;
	}

	.kmg-screen {
		padding: 14px;
	}

	.kmg-keypad {
		gap: 8px;
	}

	.kmg-key {
		min-height: 58px;
	}

	.kmg-problem-equation {
		font-size: clamp(38px, 14vw, 60px);
	}
}

/* ------------------------------------------------------------------ *
 * Reduced motion
 * ------------------------------------------------------------------ */

@media (prefers-reduced-motion: reduce) {
	.kmg-app *,
	.kmg-app *::before,
	.kmg-app *::after {
		animation-duration: 0.001s !important;
		animation-iteration-count: 1 !important;
		transition-duration: 0.001s !important;
	}
}