:root {
  --bg-color: #0d0d12;
  --primary-glow: rgba(120, 50, 255, 0.6);
  --glass-bg: rgba(255, 255, 255, 0.03);
  --glass-border: rgba(255, 255, 255, 0.08);
  --text-primary: #ffffff;
  --text-secondary: #a0a0b0;
  --health-color: #ff4757;
  --energy-color: #eccc68;
  --strength-color: #ffa502;
  --recovery-color: #7bed9f;
  --font-family: 'Inter', system-ui, sans-serif;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background-color: var(--bg-color);
  background-image: 
    radial-gradient(circle at 50% 0%, #2a1b3d 0%, transparent 60%),
    radial-gradient(circle at 80% 80%, #1a1025 0%, transparent 50%);
  color: var(--text-primary);
  font-family: var(--font-family);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  user-select: none;
}

#app {
  width: 100%;
  max-width: 1200px;
  padding: 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2rem;
}

header { text-align: center; }

h1 {
  font-size: 3rem;
  margin: 0;
  background: linear-gradient(to right, #a55eea, #45aaf2);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  filter: drop-shadow(0 0 15px var(--primary-glow));
}

.subtitle {
  color: var(--text-secondary);
  margin-top: 0.5rem;
  font-size: 1rem;
}

.game-container {
  display: grid;
  grid-template-columns: 350px 1fr;
  gap: 2rem;
  width: 100%;
}

.card {
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  border-radius: 24px;
  padding: 2rem;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
  display: flex;
  flex-direction: column;
}

.stats-panel { gap: 1.5rem; }

.stat-item {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.stat-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 600;
  font-size: 0.9rem;
  letter-spacing: 0.5px;
  color: var(--text-secondary);
}

.stat-value {
  font-size: 1.5rem;
  font-weight: 700;
  color: white;
}

.progress-bar {
  width: 100%;
  height: 6px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 3px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  border-radius: 3px;
  transition: width 0.3s ease;
  box-shadow: 0 0 10px currentColor;
}

.arena-panel {
  align-items: center;
  justify-content: center;
  position: relative;
}

.level-indicator {
  position: absolute;
  top: 2rem;
  font-size: 1.2rem;
  font-weight: 600;
  letter-spacing: 2px;
  color: var(--text-secondary);
}

.level-indicator span { color: #a55eea; }

.boss-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2rem;
  cursor: pointer;
}

.boss-emoji {
  font-size: 12rem;
  filter: drop-shadow(0 0 30px rgba(165, 94, 234, 0.4));
  transition: transform 0.1s cubic-bezier(0.175, 0.885, 0.32, 1.27);
  animation: float 4s ease-in-out infinite;
}

.boss-emoji:active { transform: scale(0.9) rotate(-5deg); }
.boss-emoji.hit { animation: shake 0.2s cubic-bezier(.36,.07,.19,.97) both; }
.boss-emoji.dead { animation: death 0.5s forwards; }

.boss-hp-bar {
  width: 300px;
  height: 10px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 5px;
  overflow: hidden;
}

.boss-hp-fill {
  height: 100%;
  background: #ff4757;
  width: 100%;
  transition: width 0.1s linear;
  box-shadow: 0 0 15px #ff4757;
}

.footer-panel {
  width: 100%;
  padding: 1rem 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

.currency-display {
  font-size: 1.2rem;
  color: var(--text-secondary);
}

.currency-value {
  color: #fff;
  font-weight: bold;
}

.upgrades-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
  width: 100%;
}

.upgrade-btn {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 12px;
  padding: 1rem;
  color: white;
  cursor: pointer;
  transition: all 0.2s;
  display: flex;
  align-items: center;
  gap: 1rem;
  text-align: left;
}

.upgrade-btn:hover:not(:disabled) {
  background: rgba(255, 255, 255, 0.1);
  transform: translateY(-2px);
  border-color: rgba(165, 94, 234, 0.5);
}

.upgrade-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  filter: grayscale(1);
}

.upgrade-icon { font-size: 2rem; }

.upgrade-info {
  display: flex;
  flex-direction: column;
}

.upgrade-name {
  font-weight: 600;
  font-size: 0.9rem;
}

.upgrade-cost {
  color: var(--energy-color);
  font-size: 0.8rem;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-20px); }
}

@keyframes shake {
  10%, 90% { transform: translate3d(-1px, 0, 0); }
  20%, 80% { transform: translate3d(2px, 0, 0); }
  30%, 50%, 70% { transform: translate3d(-4px, 0, 0); }
  40%, 60% { transform: translate3d(4px, 0, 0); }
}

@keyframes death {
  0% { transform: scale(1); opacity: 1; }
  100% { transform: scale(0); opacity: 0; }
}

.damage-number {
  position: fixed;
  color: white;
  font-weight: bold;
  font-size: 1.5rem;
  pointer-events: none;
  animation: floatUp 1s ease-out forwards;
  text-shadow: 0 0 10px rgba(0,0,0,0.5);
  z-index: 1000;
}

@keyframes floatUp {
  0% { transform: translateY(0) scale(1); opacity: 1; }
  100% { transform: translateY(-100px) scale(1.5); opacity: 0; }
}

@media (max-width: 800px) {
  .game-container { grid-template-columns: 1fr; }
  .boss-emoji { font-size: 8rem; }
}