图表组件

<div class="bg-white dark:bg-gray-800 rounded-lg shadow p-4">
  <h2 class="text-lg font-semibold mb-4 text-gray-800 dark:text-white">Sales Performance</h2>
  <div class="flex justify-between items-center mb-4">
    <div class="text-sm text-gray-500 dark:text-gray-400">Last 30 Days</div>
    <select class="text-sm text-gray-500 dark:text-gray-400 bg-transparent border-none">
      <option>Monthly</option>
      <option>Weekly</option>
      <option>Daily</option>
    </select>
  </div>
  <div class="h-40">
    <!-- Placeholder for chart -->
    <div class="flex items-end h-full">
      <div class="w-1/6 bg-blue-500 h-3/4 rounded-t dark:bg-blue-600"></div>
      <div class="w-1/6 bg-blue-500 h-2/4 rounded-t dark:bg-blue-600 ml-1"></div>
      <div class="w-1/6 bg-blue-500 h-1/4 rounded-t dark:bg-blue-600 ml-1"></div>
      <div class="w-1/6 bg-blue-500 h-full rounded-t dark:bg-blue-600 ml-1"></div>
      <div class="w-1/6 bg-blue-500 h-3/4 rounded-t dark:bg-blue-600 ml-1"></div>
      <div class="w-1/6 bg-blue-500 h-2/4 rounded-t dark:bg-blue-600 ml-1"></div>
    </div>
  </div>
</div>