:root {
      --bg: #f9fafb;
      --text: #111827;
      --card: #ffffff;
      --accent: #2563eb;
    }
    [data-theme="dark"] {
      --bg: #1f2937;
      --text: #f9fafb;
      --card: #374151;
      --accent: #3b82f6;
    }
    body {
      margin: 0;
      padding: 0;
      width: 97.9%;
      font-family: 'Segoe UI', sans-serif;
      background-color: var(--bg);
      color: var(--text);
      display: flex;
      flex-direction: column;
      align-items: center;
      padding: 0;
      transition: background-color 0.3s, color 0.3s;
    }
    nav {
      background-color: var(--card);
      width: 100%;
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 1rem 2rem;
      box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    }
    .logo {
      margin-left: 10px;
      font-size: 1.5rem;
      font-weight: bold;
      color: var(--accent);
    }
    .nav-links {
      display: flex;
      gap: 1rem;
      align-items: center;
    }
    .nav-links a {
      text-decoration: none;
      color: var(--text);
      font-weight: 500;
    }
    
    h1 {
      margin-bottom: 1rem;
    }
    .container {
      background: var(--card);
      padding: 2rem;
      border-radius: 1rem;
      box-shadow: 0 10px 25px rgba(0,0,0,0.1);
      text-align: center;
      width: 100%;
      max-width: 600px;
      margin-top: 2rem;
    }
    .drop-zone {
      border: 2px dashed var(--accent);
      padding: 1rem;
      margin-bottom: 1rem;
      cursor: pointer;
      border-radius: 1rem;
      background-color: var(--bg);
    }
    .drop-zone.dragover {
      background-color: #dbeafe;
    }
    select, button {
      margin: 1rem 0;
      padding: 0.5rem 1rem;
      border: none;
      border-radius: 0.5rem;
      background-color: var(--accent);
      color: white;
      font-size: 1rem;
      cursor: pointer;
    }
    .toggle-theme {
      margin: 0;
      cursor: pointer;
      color: var(--text);
      font-weight: 500;

    }
    .preview-list {
      display: flex;
      flex-wrap: wrap;
      gap: 1rem;
      justify-content: center;
      margin: 1rem 0;
    }
    .preview-list img {
      max-width: 100px;
      border-radius: 0.5rem;
      border: 1px solid #ccc;
    }
    footer {
      margin-top: 2rem;
      padding: 1rem;
      text-align: center;
      color: var(--text);
      background-color: var(--card);
      width: 100%;
      box-shadow: 0 -1px 5px rgba(0,0,0,0.05);
      position: fixed;
      bottom: 0;
    }