/* Explain: Styles for lesson cards and embedded lesson details. */
/* Lesson gallery tiles + embedded-lesson detail styles */
.lesson-card {
    display: flex;
    flex-direction: column;
    overflow: hidden;
    border: 1px solid var(--glass-border);
    border-radius: 1.8rem;
    background: linear-gradient(145deg, rgba(250, 249, 246, 0.82), rgba(255, 255, 255, 0.5));
    box-shadow: var(--shadow-soft);
    text-decoration: none;
    transition: transform 300ms ease, border-color 300ms ease, box-shadow 300ms ease;
}

.lesson-card:hover {
    transform: translateY(-6px);
    border-color: rgba(88, 129, 87, 0.58);
    box-shadow: 0 26px 80px rgba(31, 46, 35, 0.12);
}

.lesson-card:focus-visible {
    outline: 2px solid var(--accent-color);
    outline-offset: 3px;
}

.lesson-card-media {
    position: relative;
    aspect-ratio: 16 / 9;
    overflow: hidden;
    background: var(--surface-color);
}

.lesson-card-media img {
    height: 100%;
    width: 100%;
    object-fit: cover;
    transition: transform 500ms ease;
}

.lesson-card:hover .lesson-card-media img {
    transform: scale(1.05);
}

.lesson-play {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

.lesson-play i {
    display: inline-flex;
    height: 3.4rem;
    width: 3.4rem;
    align-items: center;
    justify-content: center;
    border-radius: 999px;
    background: rgba(31, 46, 35, 0.62);
    color: #ffffff;
    font-size: 1.05rem;
    backdrop-filter: blur(4px);
    transition: background-color 300ms ease, transform 300ms ease;
}

.lesson-card:hover .lesson-play i {
    background: var(--primary-color);
    transform: scale(1.08);
}

.lesson-duration {
    position: absolute;
    bottom: 0.7rem;
    inset-inline-end: 0.7rem;
    border-radius: 999px;
    background: rgba(31, 46, 35, 0.72);
    color: #ffffff;
    font-size: 0.72rem;
    font-weight: 700;
    padding: 0.25rem 0.7rem;
}

.lesson-card-body {
    display: flex;
    flex: 1 1 auto;
    flex-direction: column;
    gap: 0.5rem;
    padding: 1.1rem 1.2rem 1.3rem;
}

.lesson-card-title {
    color: var(--text-color);
    font-family: var(--font-heading);
    font-size: 1.2rem;
    font-weight: 600;
    line-height: 1.35;
}

.lesson-card-speaker {
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
    color: var(--sage-dark);
    font-size: 0.8rem;
    font-weight: 700;
}

.lesson-card-summary {
    color: var(--text-muted);
    font-size: 0.86rem;
    line-height: 1.65;
}

.lesson-back {
    display: inline-flex;
    min-height: 44px;
    align-items: center;
    gap: 0.5rem;
    border: 1px solid var(--glass-border);
    border-radius: 999px;
    background: rgba(250, 249, 246, 0.6);
    padding: 0.5rem 1.2rem;
    color: var(--text-color);
    font-size: 0.88rem;
    font-weight: 700;
    text-decoration: none;
    transition: border-color 300ms ease, background-color 300ms ease;
}

.lesson-back:hover {
    border-color: var(--accent-color);
    background: var(--surface-color);
}

.lesson-video-frame {
    position: relative;
    aspect-ratio: 16 / 9;
    overflow: hidden;
    border: 1px solid var(--glass-border);
    border-radius: 2rem;
    background: #000000;
    box-shadow: var(--shadow-soft);
}

.lesson-video-frame iframe {
    position: absolute;
    inset: 0;
    height: 100%;
    width: 100%;
    border: 0;
}

.lesson-video-fallback {
    display: flex;
    height: 100%;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    color: #ffffff;
    text-align: center;
}

.lesson-detail-panel {
    border: 1px solid var(--glass-border);
    border-radius: 2rem;
    background: linear-gradient(145deg, rgba(250, 249, 246, 0.82), rgba(255, 255, 255, 0.5));
    box-shadow: var(--shadow-soft);
    padding: clamp(1.5rem, 3vw, 2.2rem);
}

.lesson-topic {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 0.7rem;
    align-items: start;
    color: var(--text-color);
    font-size: 0.95rem;
    line-height: 1.6;
}

.lesson-topic-icon {
    margin-top: 0.35rem;
    color: var(--accent-color);
    font-size: 0.85rem;
}