/* Navigation */



      .worksheet-tabs {
        display: flex;
        gap: 15px;
        justify-content: center;
        flex-wrap: wrap;
        margin-bottom: 20px;
      }

      .tab-btn {
        background: linear-gradient(135deg, var(--primary), #2980b9);
        color: white;
        border: none;
        padding: 15px 30px;
        border-radius: 30px;
        cursor: pointer;
        font-size: 1.05em;
        font-weight: 600;
        transition: all 0.3s ease;
        box-shadow: 0 4px 15px rgba(52, 152, 219, 0.3);
      }

      .tab-btn:hover {
        transform: translateY(-3px);
        box-shadow: 0 6px 20px rgba(52, 152, 219, 0.4);
      }

      .tab-btn.active {
        background: linear-gradient(135deg, var(--secondary), var(--success));
        box-shadow: 0 4px 15px rgba(46, 204, 113, 0.3);
      }

      .tab-btn i {
        margin-right: 8px;
      }

      .utility-btns {
        display: flex;
        gap: 10px;
        justify-content: center;
        flex-wrap: wrap;
      }

      .util-btn {
        background: var(--light);
        color: var(--dark);
        border: 2px solid #bdc3c7;
        padding: 10px 20px;
        border-radius: 20px;
        cursor: pointer;
        font-size: 0.95em;
        transition: all 0.3s ease;
      }

      .util-btn:hover {
        background: var(--primary);
        color: white;
        border-color: var(--primary);
      }

      /* Container */
      .container {
        max-width: 1200px;
        margin: 0 auto;
        background: white;
        padding: 50px;
        border-radius: 15px;
        box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
      }

      /* Worksheets */
      .worksheet {
        display: none;
        animation: fadeIn 0.5s ease;
      }

      .worksheet.active {
        display: block;
      }


      .worksheet-header {
        text-align: center;
        margin-bottom: 40px;
        border-bottom: 4px solid var(--primary);
        padding-bottom: 25px;
      }

      .worksheet-header h2 {
        color: var(--primary);
        font-size: 2.8em;
        margin-bottom: 10px;
      }

      .worksheet-header .subtitle {
        color: #7f8c8d;
        font-style: italic;
        font-size: 1.2em;
        margin-bottom: 15px;
      }

      .instructions {
        background: linear-gradient(135deg, #ffeaa7 0%, #fdcb6e 100%);
        padding: 20px;
        border-radius: 10px;
        border-left: 5px solid var(--warning);
        margin-top: 20px;
      }

      .instructions strong {
        color: var(--dark);
      }

      /* Sections */
      .section {
        margin-bottom: 50px;
        border-left: 6px solid var(--primary);
        padding-left: 30px;
      }

      .section h3 {
        color: var(--primary);
        margin-bottom: 20px;
        font-size: 2em;
        display: flex;
        align-items: center;
        gap: 12px;
      }

      .explanation {
        background: var(--light);
        padding: 20px;
        border-radius: 10px;
        margin-bottom: 25px;
        border-left: 4px solid var(--secondary);
      }

      .explanation strong {
        color: var(--accent);
      }

      /* Examples */
      .examples {
        display: grid;
        gap: 20px;
      }

      .example-item {
        background: white;
        border: 2px solid #bdc3c7;
        padding: 20px;
        border-radius: 12px;
        transition: all 0.3s ease;
        position: relative;
        overflow: hidden;
      }

      .example-item::before {
        content: "";
        position: absolute;
        top: 0;
        left: 0;
        width: 6px;
        height: 100%;
        background: var(--primary);
        transform: scaleY(0);
        transition: transform 0.3s ease;
      }

      .example-item:hover {
        transform: translateX(10px);
        border-color: var(--primary);
        box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
      }

      .example-item:hover::before {
        transform: scaleY(1);
      }

      .phrase {
        font-weight: bold;
        color: var(--accent);
        font-size: 1.4em;
        margin-bottom: 10px;
      }

      .meaning {
        color: var(--secondary);
        font-style: italic;
        margin-bottom: 12px;
        font-weight: 600;
        font-size: 1.05em;
      }

      .sentence {
        color: var(--dark);
        padding-left: 15px;
        border-left: 3px solid var(--light);
        line-height: 1.7;
      }

      /* Tables */
      .data-table {
        width: 100%;
        border-collapse: collapse;
        margin: 25px 0;
        box-shadow: 0 3px 15px rgba(0, 0, 0, 0.1);
        border-radius: 10px;
        overflow: hidden;
      }

      .data-table th {
        background: linear-gradient(135deg, var(--primary), #2980b9);
        color: white;
        padding: 18px;
        text-align: left;
        font-weight: bold;
        font-size: 1.1em;
      }

      .data-table td {
        padding: 16px 18px;
        border-bottom: 1px solid var(--light);
      }

      .data-table tr:hover {
        background: #f8f9fa;
      }

      .data-table tr:last-child td {
        border-bottom: none;
      }

      .highlight-word {
        font-weight: bold;
        color: var(--accent);
        font-size: 1.15em;
      }

      /* Exercises */
      .exercise-box {
        background: #fff5f5;
        border: 3px dashed var(--accent);
        padding: 30px;
        border-radius: 12px;
        margin: 30px 0;
      }

      .exercise-box h4 {
        color: var(--accent);
        margin-bottom: 20px;
        font-size: 1.5em;
        display: flex;
        align-items: center;
        gap: 10px;
      }

      .exercise-question {
        margin-bottom: 25px;
        padding: 20px;
        background: white;
        border-radius: 8px;
        border-left: 5px solid var(--warning);
      }

      .exercise-question strong {
        color: var(--dark);
        display: block;
        margin-bottom: 15px;
        font-size: 1.1em;
      }

      .exercise-question p {
        margin: 12px 0;
        font-size: 1.05em;
      }

      .blank-line {
        display: inline-block;
        min-width: 220px;
        border-bottom: 2px solid #7f8c8d;
        margin: 0 8px;
      }

      /* Answer Key */
      .answer-key {
        background: var(--light);
        padding: 25px;
        border-radius: 10px;
        margin-top: 30px;
        border: 3px solid var(--secondary);
      }

      .answer-key h4 {
        color: var(--secondary);
        margin-bottom: 20px;
        display: flex;
        align-items: center;
        gap: 12px;
        font-size: 1.4em;
      }

      .answer-hidden {
        filter: blur(6px);
        user-select: none;
        transition: filter 0.3s ease;
      }

      .answer-revealed {
        filter: blur(0);
      }

      .reveal-btn {
        background: var(--secondary);
        color: white;
        border: none;
        padding: 12px 25px;
        border-radius: 25px;
        cursor: pointer;
        font-weight: 600;
        margin-top: 15px;
        transition: all 0.3s ease;
        font-size: 1.05em;
      }

      .reveal-btn:hover {
        background: var(--success);
        transform: scale(1.05);
      }

      /* Vocab Cards */
      .vocab-grid {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
        gap: 25px;
        margin: 30px 0;
      }

      .vocab-card {
        background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        color: white;
        padding: 25px;
        border-radius: 15px;
        box-shadow: 0 5px 20px rgba(0, 0, 0, 0.2);
        transition: transform 0.3s ease;
      }

      .vocab-card:hover {
        transform: translateY(-8px);
      }

      .vocab-word {
        font-size: 1.8em;
        font-weight: bold;
        margin-bottom: 12px;
      }

      .vocab-type {
        font-size: 0.95em;
        opacity: 0.9;
        margin-bottom: 12px;
      }

      .vocab-definition {
        font-size: 1.05em;
        line-height: 1.8;
      }

      /* Print Styles */
      @media print {
        body {
          background: white;
          padding: 0;
        }

        .nav-container,
        .utility-btns,
        .reveal-btn {
          display: none !important;
        }

        .container {
          box-shadow: none;
          padding: 20px;
        }

        .answer-hidden {
          filter: none;
        }

        .section {
          page-break-inside: avoid;
        }
      }

      /* Responsive */
      @media (max-width: 768px) {
        .container {
          padding: 30px 20px;
        }

        .worksheet-header h2 {
          font-size: 2.2em;
        }

        .section h3 {
          font-size: 1.6em;
        }

        .worksheet-tabs {
          flex-direction: column;
        }

        .tab-btn {
          width: 100%;
        }
      }