* {
  box-sizing: border-box;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
  background: linear-gradient(135deg, #059669, #2563eb);
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  margin: 0;
  padding: 15px;
}

.container {
  background: #ffffff;
  padding: 22px;
  border-radius: 20px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
  width: 100%;
  max-width: 380px;
  text-align: center;
}

.hidden {
  display: none !important;
}

h1 {
  color: #1f2937;
  font-size: 1.5rem;
  margin: 0 0 5px 0;
}

.subtitle {
  color: #6b7280;
  font-size: 0.85rem;
  margin-bottom: 20px;
}

.form-group {
  margin-bottom: 15px;
  text-align: left;
}

.form-group label {
  display: block;
  font-size: 0.85rem;
  font-weight: bold;
  color: #374151;
  margin-bottom: 6px;
}

.form-group select {
  width: 100%;
  padding: 10px;
  border-radius: 10px;
  border: 1px solid #d1d5db;
  font-size: 0.95rem;
  outline: none;
  background-color: #f9fafb;
}

.btn-main {
  width: 100%;
  padding: 12px;
  font-size: 1rem;
  font-weight: bold;
  color: white;
  background-color: #10b981;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  transition: 0.2s;
  margin-top: 5px;
}

.btn-main:hover {
  background-color: #059669;
}

.btn-secondary {
  padding: 6px 12px;
  font-size: 0.85rem;
  font-weight: bold;
  color: #374151;
  background-color: #f3f4f6;
  border: none;
  border-radius: 8px;
  cursor: pointer;
}

.high-score-box {
  margin-top: 20px;
  padding: 12px;
  background-color: #fef3c7;
  border: 1px dashed #f59e0b;
  border-radius: 10px;
  text-align: left;
}

.high-score-box h3 {
  margin: 0 0 5px 0;
  font-size: 0.9rem;
  color: #d97706;
}

.high-score-box p {
  margin: 0;
  font-size: 0.85rem;
  color: #4b5563;
  font-weight: bold;
}

.copyright-box {
  margin-top: 20px;
  padding-top: 12px;
  border-top: 1px solid #f3f4f6;
  font-size: 0.8rem;
  color: #9ca3af;
  line-height: 1.4;
}

/* Màn hình Trò chơi */
.game-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.map-badge {
  font-size: 0.8rem;
  font-weight: bold;
  color: #1d4ed8;
  background-color: #dbeafe;
  padding: 4px 10px;
  border-radius: 8px;
}

.score-board {
  display: flex;
  justify-content: space-around;
  background-color: #f3f4f6;
  padding: 8px;
  border-radius: 8px;
  font-size: 0.9rem;
  font-weight: bold;
  color: #374151;
  margin-bottom: 12px;
}

canvas {
  background-color: #0f172a;
  border-radius: 12px;
  box-shadow: inset 0 0 12px rgba(0, 0, 0, 0.6);
  display: block;
  margin: 0 auto 12px auto;
}

.controls-dpad {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  margin-bottom: 12px;
}

.horizontal-btns {
  display: flex;
  gap: 12px;
}

.btn-arrow {
  width: 50px;
  height: 45px;
  font-size: 1.2rem;
  background-color: #f9fafb;
  border: 1px solid #d1d5db;
  border-radius: 8px;
  cursor: pointer;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
}

.btn-arrow:active {
  background-color: #e5e7eb;
  transform: scale(0.95);
}

.message {
  font-size: 0.9rem;
  font-weight: bold;
  color: #ef4444;
  background-color: #fee2e2;
  padding: 10px;
  border-radius: 8px;
  margin-bottom: 12px;
  line-height: 1.3;
}