body {
    font-family: 'Segoe UI', sans-serif;
    background-color: #f8f9fa;
    padding-top: 75px;
}

/* Header Section */
.header-section {
    background-color: #007bff;
    color: white;
    padding: 40px 0;
    margin-bottom: 30px;
}

.header-section h1 {
    font-weight: 800;
    font-size: 2.5rem;
}

.header-section .info-bar {
    font-size: 1.1rem;
    opacity: 0.9;
    margin-top: 10px;
}

/* Main Content */
.content-area {
    padding-top: 20px;
}

.card-custom {
    background: white;
    border-radius: 10px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
    margin-bottom: 30px;
    padding: 25px;
}

/* Accordion Styles */
.accordion-button {
    font-weight: 700;
    font-size: 1.1rem;
    color: #007bff;
    background-color: #e9f5ff;
}

.accordion-button:not(.collapsed) {
    color: #fff;
    background-color: #007bff;
}

/* Lesson Item Styles */
.lesson-item {
    display: flex;
    align-items: center;
    padding: 12px 20px;
    border-bottom: 1px solid #f0f0f0;
    transition: background-color 0.2s ease;
}

.lesson-item:last-child {
    border-bottom: none;
}

.lesson-item:hover {
    background-color: #f8f9fa;
}

.lesson-item i.lesson-icon {
    width: 24px;
    text-align: center;
    margin-right: 15px;
    font-size: 1rem;
}

.lesson-item i.lesson-icon.fa-video {
    color: #dc3545;
}

.lesson-item i.lesson-icon.fa-file-alt {
    color: #17a2b8;
}

.lesson-item i.lesson-icon.fa-question-circle {
    color: #ffc107;
}

.lesson-item i.lesson-icon.fa-laptop-code {
    color: #28a745;
}

.lesson-title {
    flex-grow: 1;
    font-size: 0.95rem;
}

.lesson-meta {
    display: flex;
    align-items: center;
    gap: 15px;
    font-size: 0.85rem;
    color: #6c757d;
}

.lesson-duration {
    white-space: nowrap;
}

.lesson-preview-badge {
    background-color: #28a745;
    color: white;
    font-size: 0.7rem;
    padding: 2px 8px;
    border-radius: 10px;
    text-transform: uppercase;
}

.lesson-locked {
    color: #adb5bd;
}

/* Enrollment Card */
.enroll-card {
    position: sticky;
    top: 100px;
    background: white;
    padding: 0;
    border-radius: 10px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    overflow: hidden;
}

.enroll-card .media-placeholder {
    height: 200px;
    width: 100%;
    background-color: #e6f0ff;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.enroll-card .media-placeholder img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.enroll-card .card-content {
    padding: 20px;
}

.enroll-card .price-tag {
    font-size: 2.5rem;
    font-weight: 800;
    color: #28a745;
    margin-bottom: 15px;
}

.enroll-card .btn-buy, .enroll-card .btn-enroll {
    width: 100%;
    font-weight: 700;
    padding: 12px;
    margin-bottom: 10px;
}

.enroll-card .guarantee-box {
    text-align: center;
    font-size: 0.9rem;
    color: #6c757d;
    border-top: 1px dashed #e9ecef;
    padding-top: 15px;
    margin-top: 15px;
}

/* Features List */
.features-list {
    list-style: none;
    padding-left: 0;
}

.features-list li {
    padding: 5px 0;
    font-size: 1rem;
}

.features-list li i {
    color: #28a745;
    margin-right: 10px;
}

.original-price {
    text-decoration: line-through;
    color: #999;
    font-size: 1.5rem;
    margin-right: 10px;
}

.badge-category {
    background-color: #ffc107;
    color: #333;
    padding: 5px 10px;
    border-radius: 5px;
    font-size: 0.9rem;
    margin-bottom: 10px;
    display: inline-block;
}

.login-prompt {
    background-color: #fff3cd;
    border: 1px solid #ffc107;
    border-radius: 5px;
    padding: 15px;
    margin-bottom: 15px;
    text-align: center;
}

.login-prompt a {
    color: #007bff;
    font-weight: bold;
}

/* Course Content Summary */
.course-content-summary {
    font-size: 0.95rem;
    color: #6c757d;
    margin-bottom: 15px;
}

/* Chapter description */
.chapter-description {
    font-size: 0.9rem;
    color: #6c757d;
    padding: 10px 20px;
    background-color: #f8f9fa;
    border-bottom: 1px solid #f0f0f0;
}

/* No content message */
.no-content-message {
    text-align: center;
    padding: 40px 20px;
    color: #6c757d;
}

.no-content-message i {
    font-size: 3rem;
    margin-bottom: 15px;
    color: #dee2e6;
}

/* Chapter lesson count badge */
.chapter-lesson-badge {
    font-size: 0.75rem;
    font-weight: normal;
    margin-left: 10px;
}