/* === BASE === */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --font-display: 'Cabinet Grotesk', sans-serif;
  --font-body: 'Satoshi', sans-serif;
  --color-bg: #0d1117;
  --color-surface: rgba(255,255,255,0.06);
  --color-text: #e6edf3;
  --color-text-muted: #8b949e;
  --color-accent: #f0c040;
  --color-accent-glow: rgba(240,192,64,0.3);
  --color-danger: #ff6b6b;
  --color-track: #3b82f6;
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
}

html, body {
  width: 100%; height: 100%;
  overflow: hidden;
  background: var(--color-bg);
  font-family: var(--font-body);
  color: var(--color-text);
  -webkit-font-smoothing: antialiased;
}

canvas {
  display: block;
  width: 100%; height: 100%;
  position: fixed; inset: 0;
}

/* === UI OVERLAY === */
#ui-overlay {
  position: fixed; inset: 0;
  pointer-events: none;
  z-index: 10;
}

.screen {
  position: absolute; inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transition: opacity 0.5s var(--ease-out);
  pointer-events: none;
}
.screen.active {
  opacity: 1;
  pointer-events: none; /* let clicks pass through to document listener */
}

/* === START SCREEN === */
.title {
  font-family: var(--font-display);
  font-size: clamp(2.5rem, 5vw, 4.5rem);
  font-weight: 900;
  letter-spacing: -0.02em;
  line-height: 1.1;
  color: var(--color-text);
  text-align: center;
}

.subtitle {
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: var(--color-text-muted);
  margin-top: 12px;
  text-align: center;
  max-width: 420px;
  line-height: 1.5;
}

.btn-primary {
  margin-top: 32px;
  padding: 14px 40px;
  font-family: var(--font-body);
  font-size: 16px;
  font-weight: 600;
  color: #0d1117;
  background: var(--color-accent);
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: transform 180ms var(--ease-out), box-shadow 180ms var(--ease-out);
  pointer-events: none; /* inherit from parent screen */
}
.screen.active .btn-primary {
  pointer-events: auto;
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px var(--color-accent-glow);
}
.btn-primary:active {
  transform: translateY(0);
}

/* === PUSH PROMPT === */
#push-prompt {
  justify-content: flex-end;
  padding-bottom: 6vh;
}

.prompt-box {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  padding: 20px 36px;
  background: rgba(13,17,23,0.88);
  backdrop-filter: blur(12px);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 12px;
}

.prompt-icon {
  color: var(--color-accent);
  animation: pulse 1.2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { transform: scale(1); opacity: 0.7; }
  50% { transform: scale(1.15); opacity: 1; }
}

.prompt-text {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-text);
}

.push-meter-container {
  width: 240px;
}

.push-meter-bg {
  width: 100%;
  height: 10px;
  background: rgba(255,255,255,0.1);
  border-radius: 5px;
  overflow: hidden;
}

.push-meter-fill {
  width: 0%;
  height: 100%;
  background: linear-gradient(90deg, var(--color-accent), #ff8c00);
  border-radius: 5px;
  transition: width 60ms linear;
}

/* === OBSTACLE POPUP === */
#obstacle-popup {
  justify-content: flex-start;
  padding-top: 4vh;
}

.obstacle-label {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3.5vw, 2.8rem);
  font-weight: 800;
  color: var(--color-danger);
  text-align: center;
  text-shadow: 0 0 30px rgba(255,107,107,0.5), 0 2px 8px rgba(0,0,0,0.6);
  transform: scale(0.6);
  opacity: 0;
  transition: transform 0.4s var(--ease-out), opacity 0.3s var(--ease-out);
  padding: 0 24px;
}

.obstacle-label.visible {
  transform: scale(1);
  opacity: 1;
}

/* === FINISH SCREEN === */
.finish-title {
  color: var(--color-danger);
}
.finish-sub {
  max-width: 540px;
}
.finish-sub strong {
  color: var(--color-accent);
}

/* === AXIS LABELS === */
.axis-label {
  position: absolute;
  font-size: 13px;
  font-weight: 600;
  color: var(--color-text-muted);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  opacity: 0;
  transition: opacity 0.6s var(--ease-out);
}
.axis-label.visible {
  opacity: 1;
}
#y-axis-label {
  left: 20px;
  top: 50%;
  transform: rotate(-90deg) translateX(-50%);
  transform-origin: left center;
}
#x-axis-label {
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
}

/* === MOBILE HINT === */
@media (hover: none) {
  .prompt-text::after {
    content: ' (Tap)';
  }
}