/* Free content part */

.student-container {
            max-width: 1200px;
            margin: auto;
            padding: 30px 20px;
        }

        .student-filters {
            display: flex;
            gap: 10px;
            flex-wrap: wrap;
            margin-bottom: 20px;
        }

        .student-filters select,
        .student-filters button {
            padding: 10px;
            font-size: 15px;
            border: 1px solid #ccc;
            border-radius: 6px;
        }

        .student-filters button {
            background-color: #8e24aa;
            color: white;
            border: none;
            cursor: pointer;
        }

        .student-filters button:hover {
            background-color: #6a1b9a;
        }

        .student-content-area {
            display: flex;
            flex-wrap: wrap;
            gap: 20px;
        }

        .chapter-sidebar {
            width: 250px;
            background-color: #ffffff;
            border: 1px solid #ddd;
            border-radius: 8px;
            padding: 15px;
        }

        .chapter-sidebar h4 {
            margin-bottom: 15px;
        }

        .chapter-sidebar ul {
            list-style: none;
            padding: 0;
        }

        .chapter-sidebar li {
            margin-bottom: 10px;
            font-size: 14px;
            display: flex;
            justify-content: space-between;
            border-bottom: 1px dashed #ccc;
            padding-bottom: 4px;
        }

        .chapter-sidebar a {
            text-decoration: none;
            color: #8e24aa;
            font-weight: bold;
        }

        .chapter-sidebar a:hover {
            text-decoration: underline;
        }

        .pdf-viewer {
            flex: 1;
            min-width: 300px;
            background-color: white;
            border-radius: 8px;
            box-shadow: 0 0 8px rgba(0, 0, 0, 0.1);
            overflow: hidden;
            padding: 10px;
        }

        .pdf-viewer iframe {
            width: 100%;
            height: 600px;
            border: none;
        }

        @media (max-width: 768px) {
            .student-content-area {
                flex-direction: column;
            }

            .chapter-sidebar {
                width: 100%;
            }

            .pdf-viewer iframe {
                height: 400px;
            }
        }