.upgrade-shop {
  background-color: white;
  border-radius: 8px;
  padding: 15px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  flex: 1;
}

.upgrade-shop h2 {
  font-size: 22px;
  margin-bottom: 15px;
  color: #333;
  border-bottom: 2px solid #eee;
  padding-bottom: 10px;
}

.upgrades-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  max-height: 500px;
  overflow-y: auto;
  padding-right: 5px;
}

.upgrade-item {
  display: flex;
  padding: 12px;
  border-radius: 6px;
  transition: background-color 0.2s, transform 0.1s;
  border: 1px solid #ddd;
  gap: 12px;
  cursor: pointer;
}

.upgrade-item:hover {
  background-color: #f5f5f5;
}

.can-afford {
  border-left: 4px solid #27ae60;
}

.can-afford:hover {
  transform: translateX(2px);
}

.cannot-afford {
  opacity: 0.7;
  cursor: not-allowed;
  border-left: 4px solid #e74c3c;
}

.maxed-out {
  border-left: 4px solid #f39c12;
  background-color: #ffefd5;
}

.upgrade-icon {
  font-size: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 40px;
}

.upgrade-info {
  flex: 1;
}

.upgrade-info h3 {
  font-size: 16px;
  margin-bottom: 3px;
}

.upgrade-info p {
  font-size: 14px;
  color: #666;
  margin-bottom: 5px;
}

.upgrade-value {
  font-weight: bold;
  color: #2980b9 !important;
}

.upgrade-cost {
  font-weight: bold;
  color: #e67e22 !important;
}

.max-level {
  font-weight: bold;
  color: #f39c12 !important;
}

/* Mobile optimization */
@media (max-width: 768px) {
  .upgrade-item {
    padding: 10px;
  }
  
  .upgrade-icon {
    font-size: 20px;
    min-width: 30px;
  }
  
  .upgrade-info h3 {
    font-size: 14px;
  }
  
  .upgrade-info p {
    font-size: 12px;
  }
}