html, body {
	margin: 0;
	padding: 0;
	background: #0b0f14;
	font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Helvetica Neue', Arial, sans-serif;
	color: #e2eef7;
	height: 100%;
}

#game-root {
	position: relative;
	max-width: 720px;
	margin: 0 auto;
	height: 100vh;
	display: flex;
	align-items: center;
	justify-content: center;
}

#game-canvas {
	width: 100%;
	height: auto;
	background: #051018;
	border: 2px solid #0e2a3d;
	box-shadow: 0 10px 30px rgba(0,0,0,.4);
}

#hud {
	position: absolute;
	top: 12px;
	left: 12px;
	right: 12px;
	display: flex;
	align-items: center;
	justify-content: space-between;
	pointer-events: none;
}

.score {
	font-weight: 700;
	letter-spacing: .5px;
}

#btn-restart, #btn-play {
	pointer-events: all;
	background: #1d6fb8;
	color: #fff;
	border: none;
	padding: 10px 16px;
	border-radius: 8px;
	font-weight: 600;
	cursor: pointer;
	box-shadow: 0 6px 16px rgba(29,111,184,.35);
}

#btn-restart.hidden { display: none; }

.overlay {
	position: absolute;
	inset: 0;
	background: rgba(5,16,24,.86);
	display: flex;
	align-items: center;
	justify-content: center;
}

.overlay.hidden { display: none; }

.panel {
	background: #0c1b27;
	border: 1px solid #14334a;
	border-radius: 12px;
	padding: 20px 18px;
	max-width: 90%;
	text-align: center;
	box-shadow: 0 10px 24px rgba(0,0,0,.4);
}

.panel h1 { margin: 0 0 8px; font-size: 24px; }
.panel p { margin: 8px 0; color: #b9d1e0; }
.panel ul { text-align: left; margin: 8px auto 16px; max-width: 320px; }
.panel li { margin: 4px 0; color: #c7dceb; }

@media (max-width: 480px) {
	#hud { font-size: 14px; }
	#btn-restart, #btn-play { padding: 10px 14px; }
}