:root {
    --primary-color: #ffc815;
    --secondary-color: #585858;
    --text-primary: #333333;
    --text-secondary: #666666;
    --bg-light: #f8f9fa;
    --card-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    --card-hover-shadow: 0 8px 30px rgba(0, 0, 0, 0.15);
    --transition: all 0.3s ease;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 20px;
    text-align: center;
}

.course-header {
    margin-bottom: 2rem;
    position: relative;
    text-align: center;
}

.course-title {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text-primary);
    margin-bottom: 1rem;
    line-height: 1.2;
    text-align: center;
}

.course-category {
    display: inline-block;
    padding: 0.5rem 1rem;
    background-color: rgba(255, 200, 21, 0.1);
    border-radius: 20px;
    color: var(--text-primary);
    font-weight: 500;
    margin-bottom: 1rem;
    text-align: center;
}

.course-info-container {
    background: #ffffff;
    border-radius: 20px;
    box-shadow: var(--card-shadow);
    padding: 30px;
    margin-bottom: 30px;
    transition: var(--transition);
    text-align: center;
}

.course-info-container:hover {
    box-shadow: var(--card-hover-shadow);
}

.course-thumbnail {
    width: 100%;
    height: 300px;
    object-fit: cover;
    border-radius: 15px;
    margin-bottom: 1.5rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.no-thumbnail {
    height: 300px;
    background: linear-gradient(135deg, #f5f5f5 0%, #e0e0e0 100%);
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.course-description {
    color: var(--text-secondary);
    font-size: 1.1rem;
    line-height: 1.8;
    margin: 1.5rem 0 2.5rem;
    padding: 2rem;
    background: linear-gradient(to right, rgba(255, 200, 21, 0.05), rgba(255, 255, 255, 0.8));
    border-radius: 16px;
    border-left: 4px solid var(--primary-color);
    box-shadow: 0 2px 15px rgba(0, 0, 0, 0.05);
    position: relative;
    transition: var(--transition);
    text-align: left;
}

.course-description:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.course-description p {
    margin-bottom: 1.2rem;
}

.course-description p:last-child {
    margin-bottom: 0;
}

.course-description::before {
    content: '"';
    position: absolute;
    top: -10px;
    left: 20px;
    font-size: 4rem;
    color: var(--primary-color);
    opacity: 0.2;
    font-family: Georgia, serif;
}

.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin: 2rem auto 1rem;
    padding-bottom: 0.5rem;
    display: block;
    text-align: center;
}

.section-title::after {
    content: "";
    display: block;
    width: 20%;
    height: 3px;
    background-color: var(--primary-color);
    margin: 5px auto;
}

.course-video {
    margin: 1.5rem 0;
}

.video-link {
    display: inline-flex;
    align-items: center;
    padding: 0.8rem 1.5rem;
    background-color: var(--primary-color);
    border-radius: 12px;
    color: var(--text-primary);
    text-decoration: none;
    transition: var(--transition);
}

.video-link:hover {
    background-color: var(--secondary-color);
    color: var(--primary-color);
    transform: translateY(-2px);
}

.price-tag {
    font-size: 2rem;
    font-weight: 800;
    color: var(--text-primary);
    margin: 1.5rem 0;
    padding: 1rem;
    background: rgba(255, 200, 21, 0.1);
    border-radius: 15px;
    text-align: center;
}

.btn-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    margin-top: 1.5rem;
}

.btn-custom {
    background-color: var(--primary-color);
    color: var(--text-primary);
    padding: 12px 24px;
    border-radius: 25px;
    border: none;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    display: inline-block;
    transition: var(--transition);
    text-align: center;
    cursor: pointer;
    width: 60%;
    margin: 0.5rem auto;
}

.btn-custom:hover {
    background-color: var(--secondary-color);
    color: var(--primary-color);
    transform: translateY(-2px);
}

.btn-purchase {
    background-color: var(--primary-color);
    color: var(--text-primary);
}

.btn-purchase:hover {
    background-color: var(--secondary-color);
    color: var(--primary-color);
}

#pdfOverlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

#pdfContainer {
    background-color: #fff;
    padding: 20px;
    border-radius: 10px;
    width: 80%;
    height: 80%;
    max-width: 1000px;
    max-height: 80vh;
    overflow: hidden;
    position: relative;
}

iframe {
    width: 100%;
    height: 100%;
    border: none;
    overflow: hidden;
}

#closePdfBtn {
    background-color: var(--primary-color);
    border: none;
    padding: 15px 20px;
    border-radius: 5px;
    cursor: pointer;
    position: absolute;
    top: 18px;
    right: 10px;
    z-index: 1100;
}

#closePdfBtn:hover {
    background-color: var(--secondary-color);
    color: var(--primary-color);
}

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

    .course-title {
        font-size: 2rem;
    }

    .course-thumbnail {
        height: 200px;
    }

    .price-tag {
        font-size: 1.5rem;
    }

    .btn-custom {
        width: 80%;
    }
}