/* ========================================
   LESSON HEADER (Generic)
   ======================================== */

.lesson-header {
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary-medium) 100%);
    color: white;
    padding: 2rem;
    position: relative;
}

.lesson-header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 20"><defs><radialGradient id="a" cx="50%25" cy="0%25" r="100%25"><stop offset="0%25" stop-color="%23fff" stop-opacity=".05"/><stop offset="100%25" stop-color="%23fff" stop-opacity="0"/></radialGradient></defs><rect width="100" height="20" fill="url(%23a)"/></svg>') repeat-x;
    opacity: 0.3;
}

/* ========================================
   BREADCRUMB NAVIGATION
   ======================================== */

.breadcrumb-nav {
    font-size: 0.875rem;
    margin-bottom: 1.5rem;
    position: relative;
    z-index: 2;
}

.breadcrumb-nav a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: color 0.3s ease;
}

.breadcrumb-nav a:hover {
    color: white;
    text-decoration: underline;
}

.breadcrumb-nav .separator {
    margin: 0 0.5rem;
    opacity: 0.6;
}

/* ========================================
   COURSE/SERIES INFO
   ======================================== */

.course-info {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
    position: relative;
    z-index: 2;
}

.instructor-avatar {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    object-fit: cover;
}

.author-details h4 {
    font-size: 1rem;
    font-weight: 600;
    margin: 0;
}

/* ========================================
   LESSON ACTIONS
   ======================================== */

.lesson-actions {
    position: absolute;
    top: 2rem;
    right: 2rem;
    display: flex;
    gap: 0.5rem;
    z-index: 3;
}

.action-btn {
    width: 40px;
    height: 40px;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.1);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    transition: var(--transition);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.action-btn:hover {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    text-decoration: none;
    transform: translateY(-2px);
}

/* ========================================
   LESSON TITLE
   ======================================== */

.lesson-title {
    font-size: 2.25rem;
    font-weight: bold;
    margin-bottom: 0.75rem;
    line-height: 1.2;
    position: relative;
    z-index: 2;
}

/* ========================================
   LESSON METADATA
   ======================================== */

.lesson-metadata {
    display: flex;
    flex-wrap: wrap;
    gap: 1.5rem;
    align-items: center;
    position: relative;
    z-index: 2;
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.9rem;
    opacity: 0.9;
}

.meta-icon {
    font-size: 0.875rem;
}

.lesson-badge {
    background: var(--accent-green);
    color: white;
    padding: 0.375rem 0.75rem;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
}

/* ========================================
   RESPONSIVE
   ======================================== */

@media (max-width: 768px) {
    .lesson-header {
        padding: 1.5rem;
    }

    .lesson-title {
        font-size: 1.75rem;
    }

    .lesson-actions {
        top: 1.5rem;
        right: 1.5rem;
    }
}