:root {
  --bg-primary: #0b0f19;
  --bg-card: rgba(18, 26, 44, 0.85);
  --accent-cyan: #00f0ff;
  --accent-green: #00ff88;
  --accent-red: #ff3366;
  --accent-amber: #ffb703;
  --accent-purple: #9d4edd;
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --font-thai: 'Kanit', sans-serif;
  --font-en: 'Outfit', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  user-select: none;
}

body {
  background-color: var(--bg-primary);
  background-image: 
    radial-gradient(circle at 15% 20%, rgba(0, 240, 255, 0.08) 0%, transparent 40%),
    radial-gradient(circle at 85% 80%, rgba(157, 78, 221, 0.08) 0%, transparent 40%),
    linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
  background-size: 100% 100%, 100% 100%, 36px 36px, 36px 36px;
  color: var(--text-main);
  font-family: var(--font-thai);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  overflow-x: hidden;
}

/* Header */
.app-header {
  width: 100%;
  max-width: 1200px;
  padding: 12px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(12px);
  z-index: 10;
}

.logo-group {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.badge-tag {
  font-family: var(--font-en);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 1.5px;
  color: var(--accent-cyan);
  text-transform: uppercase;
}

.game-title {
  font-size: 1.35rem;
  font-weight: 700;
  background: linear-gradient(90deg, #ffffff, #00f0ff);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.status-indicator {
  display: flex;
  align-items: center;
  gap: 10px;
  background: rgba(0, 0, 0, 0.4);
  padding: 6px 14px;
  border-radius: 99px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 0.85rem;
  color: var(--text-muted);
}

.status-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: #ffb703;
  box-shadow: 0 0 10px #ffb703;
  transition: all 0.3s;
}

.status-dot.active {
  background: var(--accent-green);
  box-shadow: 0 0 12px var(--accent-green);
}

.mode-toggle-btn {
  background: rgba(0, 240, 255, 0.12);
  border: 1px solid rgba(0, 240, 255, 0.3);
  color: var(--accent-cyan);
  padding: 4px 10px;
  border-radius: 6px;
  font-family: var(--font-thai);
  font-size: 0.75rem;
  cursor: pointer;
  transition: all 0.2s ease;
}

.mode-toggle-btn:hover {
  background: rgba(0, 240, 255, 0.25);
  transform: translateY(-1px);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.difficulty-group {
  display: flex;
  background: rgba(0, 0, 0, 0.4);
  padding: 3px;
  border-radius: 99px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  gap: 4px;
}

.diff-btn {
  background: transparent;
  border: none;
  color: #94a3b8;
  padding: 4px 10px;
  border-radius: 99px;
  font-family: var(--font-thai);
  font-size: 0.75rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.diff-btn:hover {
  color: #ffffff;
  background: rgba(255, 255, 255, 0.1);
}

.diff-btn.active {
  background: rgba(0, 240, 255, 0.2);
  color: var(--accent-cyan);
  border: 1px solid rgba(0, 240, 255, 0.5);
  box-shadow: 0 0 10px rgba(0, 240, 255, 0.3);
}

.diff-btn[data-diff="EASY"].active {
  background: rgba(0, 255, 136, 0.2);
  color: var(--accent-green);
  border: 1px solid rgba(0, 255, 136, 0.5);
  box-shadow: 0 0 10px rgba(0, 255, 136, 0.3);
}

.diff-btn[data-diff="HARD"].active {
  background: rgba(255, 51, 102, 0.2);
  color: var(--accent-red);
  border: 1px solid rgba(255, 51, 102, 0.5);
  box-shadow: 0 0 10px rgba(255, 51, 102, 0.3);
}

.nav-btn {
  text-decoration: none;
  background: rgba(255, 255, 255, 0.05);
  color: #cbd5e1;
  padding: 7px 12px;
  border-radius: 8px;
  font-size: 0.82rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  transition: all 0.2s;
}

.nav-btn:hover {
  background: rgba(255, 255, 255, 0.12);
  color: #fff;
  border-color: rgba(255, 255, 255, 0.25);
}

.btn {
  padding: 7px 16px;
  font-family: var(--font-thai);
  font-size: 0.85rem;
  font-weight: 600;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-restart {
  background: linear-gradient(135deg, #ff007f, #8338ec);
  color: white;
  box-shadow: 0 4px 14px rgba(255, 0, 127, 0.3);
}

.btn-restart:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 18px rgba(255, 0, 127, 0.45);
}

/* Container */
.game-container {
  position: relative;
  margin: 16px auto;
  width: 1100px;
  max-width: 96vw;
  height: 680px;
  border-radius: 20px;
  overflow: hidden;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.6), 0 0 0 1px rgba(255, 255, 255, 0.1);
  background: #060913;
}

#webcam {
  display: none;
  position: absolute;
  top: 0;
  left: 0;
}

#gameCanvas {
  width: 100%;
  height: 100%;
  display: block;
  cursor: crosshair;
}