.topic-thumbnail {
    position: relative;
    width: 100%;
    height: 200px;
    overflow: hidden;
    background-color: #f8f9fa;
}

.topic-thumbnail.landscape {
    height: 200px;
}

.topic-thumbnail.portrait {
    height: 200px;
}

.topic-thumbnail img,
.topic-thumbnail video.topic-card-video {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.topic-thumbnail:hover img,
.topic-thumbnail:hover video.topic-card-video {
    transform: scale(1.05);
}

.topic-card {
    border: none;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    height: auto;
    margin-bottom: 2rem;
}

.topic-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.post-card {
    border: 1px solid rgba(0,0,0,0.1);
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.post-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 3px 6px rgba(0,0,0,0.1);
}

.card-title {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
    line-height: 1.4;
}

.card-text {
    color: #6c757d;
    margin-bottom: 0.75rem;
}

.badge {
    font-size: 0.75rem;
    padding: 0.25em 0.6em;
}

.video-play-overlay {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 48px;
    height: 48px;
    background: rgba(0, 0, 0, 0.55);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 18px;
    pointer-events: none;
    transition: opacity 0.25s ease;
    z-index: 2;
}

.video-play-overlay i {
    margin-left: 3px;
}

.feature-btn {
    transition: all 0.2s ease;
}

.feature-btn:hover {
    transform: scale(1.05);
}