* {
  box-sizing: border-box;
}

body {
  font-family: "Comic Sans MS", "Segoe UI", Arial, sans-serif;
  background: linear-gradient(135deg, #065f46 0%, #047857 25%, #0d9488 50%, #134e4a 75%, #065f46 100%);
  background-size: 300% 300%;
  animation: gradientShift 14s ease infinite;
  position: relative;
  overflow-x: hidden;
}

@keyframes gradientShift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

.card {
  width: 100%;
  max-width: 480px;
  margin: 0 auto;
  background: rgba(255, 255, 255, 0.96);
  border-radius: 24px;
  padding: 24px 20px 32px;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.4);
  position: relative;
  z-index: 1;
}

.levels { display: flex; gap: 8px; margin-bottom: 20px; }

.lvl-btn {
  flex: 1;
  padding: 10px;
  border-radius: 10px;
  border: 2px solid #a7f3d0;
  background: #ecfdf5;
  font-size: 15px;
  cursor: pointer;
  font-family: inherit;
}

.lvl-btn.active {
  background: linear-gradient(135deg, #10b981, #047857);
  border-color: #065f46;
  color: #fff;
  font-weight: 700;
}

.stats { display: flex; gap: 10px; margin-bottom: 20px; }

.stat {
  flex: 1;
  background: #d1fae5;
  border-radius: 10px;
  padding: 10px;
  text-align: center;
}

.stat .label { font-size: 12px; color: #047857; font-weight: 700; }
.stat .value { font-size: 22px; font-weight: 800; color: #064e3b; margin-top: 2px; }

.question-box {
  background: #f0fdf4;
  border: 1px solid #a7f3d0;
  border-radius: 14px;
  padding: 24px 16px;
  text-align: center;
  margin-bottom: 20px;
}

#item-display {
  margin-bottom: 20px;
}

#item-emoji {
  display: block;
  font-size: 56px;
  margin-bottom: 8px;
}

#item-label {
  font-size: 18px;
  font-weight: 800;
  color: #064e3b;
}

.bins {
  display: grid;
  gap: 10px;
}

.bin {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 14px 6px;
  border-radius: 14px;
  border: 2px solid #6ee7b7;
  background: #fff;
  cursor: pointer;
  transition: transform 0.12s ease, background 0.12s ease;
}

.bin:hover {
  transform: translateY(-2px);
  background: #ecfdf5;
}

.bin-icon { font-size: 26px; }
.bin-label { font-size: 13px; font-weight: 700; color: #065f46; }

#feedback {
  min-height: 20px;
  margin-top: 16px;
  font-weight: 700;
  font-size: 14px;
}

.feedback-correct { color: #15803d; }
.feedback-wrong { color: #dc2626; }
.feedback-info { color: #047857; }

.actions { display: flex; }

.action-btn {
  flex: 1;
  padding: 12px;
  border-radius: 10px;
  border: none;
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
  font-family: inherit;
}

.check-btn { background: #059669; color: #fff; }
.check-btn:hover { background: #047857; }