:root {
  /* Backgrounds — neutral dark gray, no blue/purple tint */
  --bg-primary:   #1e1e1e;
  --bg-secondary: #262626;
  --bg-card:      #2e2e2e;

  /* Accent — anatomical red */
  --accent:       #EF5350;
  --accent-hover: #F87171;

  /* Text — soft white, no pure #fff */
  --text-primary:   #F5F5F5;
  --text-secondary: #A1A1AA;
  --text-muted:     #71717A;

  /* Borders */
  --border: #2a2a2a;

  /* Semantic */
  --success:  #34D399;
  --warning:  #FBBF24;

  /* Proximity */
  --hot:      #EF5350;
  --warm:     #FBBF24;
  --cool:     #38BDF8;
  --freezing: #A78BFA;

  /* Unchanged */
  --radius:     8px;
  --radius-lg:  12px;
  --transition: 0.2s ease;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
}

#app {
  display: flex;
  flex-direction: column;
  min-height: 100dvh;
  max-width: 520px;
  margin: 0 auto;
  width: 100%;
  padding: 0 16px;
}

.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 0;
  border-bottom: 1px solid var(--border);
}

.header-title {
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: 0.15em;
  color: var(--accent);
}

.header-right {
  display: flex;
  gap: 8px;
}

.header-btn {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-primary);
  font-size: 1rem;
  font-weight: 700;
  transition: background var(--transition);
}

.header-btn:hover {
  background: var(--bg-secondary);
}

.game-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  padding: 16px 0;
}

.game-message {
  text-align: center;
  font-weight: 600;
  min-height: 1.5em;
}

.ad-slot {
  display: flex;
  justify-content: center;
  padding: 16px 0;
  min-height: 50px;
}

.footer {
  text-align: center;
  padding: 12px 0;
  color: var(--text-muted);
  font-size: 0.75rem;
  border-top: 1px solid var(--border);
}

@media (min-width: 480px) {
  .header-title {
    font-size: 1.75rem;
  }
}

@media (min-width: 768px) {
  .ad-slot {
    min-height: 90px;
  }
}