body {
        background-color: #f8f9fa;
        font-family: 'Arial', sans-serif;
        font-size: 1.2rem;
        line-height: 1.8;
        color: #212529;
    }
    .container {
        max-width: 1100px;
        margin: auto;
    }
    h1 {
        font-size: 2.5rem;
        color: #007bff;
    }
    h2 {
        font-size: 2rem;
        color: #343a40;
    }
    h3 {
        font-size: 1.8rem;
        color: #343a40;
    }
    h4 {
        font-size: 1.5rem;
        color: #007bff;
    }
    .tabs {
        display: flex;
        justify-content: center;
        gap: 10px;
        margin-bottom: 30px;
        flex-wrap: wrap;
    }
    .tab-link {
        padding: 14px 24px;
        cursor: pointer;
        background: #e0e0e0;
        border-radius: 3px;
        border: none;
        font-size: 18px;
        transition: background 0.3s, color 0.3s;
    }
    .tab-link:hover {
        background: #007bff;
        color: white;
    }
    .tab-link.active {
        background: #007bff;
        color: white;
        font-weight: bold;
    }
    .tab-content {
        display: none;
        padding: 20px;
        border-radius: 5px;
        background: #ffffff;
        border: 1px solid #dee2e6;
    }
    .tab-content.active {
        display: block;
    }
    .language-card, .vocab-card, .grammar-card, .glossary-card, .exercise-card, .passage-card {
        transition: transform 0.2s;
        border: 1px solid #dee2e6;
        background: #ffffff;
        margin-bottom: 20px;
    }
    .language-card:hover, .vocab-card:hover, .grammar-card:hover, .glossary-card:hover, .exercise-card:hover, .passage-card:hover {
        transform: translateY(-5px);
        box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    }
    .audio-btn {
        font-size: 18px;
        padding: 8px 16px;
        margin-bottom: 10px;
        background-color: #007bff;
        border-color: #007bff;
    }
    .audio-btn:hover {
        background-color: #0056b3;
        border-color: #0056b3;
    }
    .collapse-btn {
        font-size: 16px;
        padding: 8px 15px;
        margin-bottom: 10px;
        background-color: #6c757d;
        border-color: #6c757d;
    }
    .collapse-btn:hover {
        background-color: #5a6268;
        border-color: #5a6268;
    }
    .note {
        font-style: italic;
        color: #6c757d;
        font-size: 16px;
        margin-top: 10px;
    }
    #audio-feedback {
        position: fixed;
        top: 20px;
        left: 20px;
        z-index: 1000;
        width: 300px;
    }
    .vocab-card p, .grammar-card p, .glossary-card p, .exercise-card p, .passage-card p {
        margin-bottom: 0.5rem;
        color: #212529;
    }
    .vocab-card .card p strong, .grammar-card .card p strong, .glossary-card .card p strong {
        color: #007bff;
    }
    .draggable, .draggable-word {
        cursor: move;
        user-select: none;
    }
    .draggable.dragging, .draggable-word.dragging {
        opacity: 0.5;
    }
    .droppable, .droppable-sentence {
        min-height: 50px;
        border: 2px dashed #6c757d;
        padding: 10px;
        background: #f8f9fa;
        margin-bottom: 10px;
    }
    .droppable:hover, .droppable-sentence:hover {
        background: #e9ecef;
    }
    .form-control.d-inline-block {
        width: 100px;
        display: inline-block;
        margin: 0 5px;
    }
    .alert-success, .alert-warning, .alert-danger {
        padding: 10px;
        border-radius: 5px;
        margin-top: 10px;
    }
    .list-group-item {
        margin-bottom: 5px;
        border: 1px solid #dee2e6;
    }
    .collapse {
        margin-top: 15px;
        padding: 10px;
        background: #f8f9fa;
        border: 1px solid #dee2e6;
        border-radius: 5px;
    }

.sentence-drag-list .draggable-word {
    display: inline-block;
    margin-right: 8px; /* Space between words */
    padding: 2px 5px; /* Optional: slight padding for readability */
    cursor: move; /* Indicate draggability */
}

.droppable-sentence .draggable-word {
    display: inline-block;
    margin: 0 5px; /* Consistent spacing in droppable area */
}
    @media (max-width: 576px) {
        body {
            font-size: 1.1rem;
        }
        h1 {
            font-size: 2rem;
        }
        h2 {
            font-size: 1.8rem;
        }
        h3 {
            font-size: 1.6rem;
        }
        h4 {
            font-size: 1.4rem;
        }
        .dialogue-card, .passage-card, .vocab-card, .grammar-card, .glossary-card, .exercise-card {
            font-size: 1rem;
        }
        .tab-link {
            font-size: 1rem;
            padding: 10px 18px;
        }
        .audio-btn, .collapse-btn {
            font-size: 1rem;
            padding: 8px 16px;
        }
        .form-control.d-inline-block {
            width: 80px;
        }
        #audio-feedback {
            width: 90%;
        }
    }