/* 话题详情页样式 */

/* ========== 头部导航 ========== */
.topic-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background: var(--card-bg);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 var(--spacing-md);
    z-index: var(--z-sticky);
    border-bottom: 1px solid var(--border-color);
}

.btn-back,
.btn-share {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-full);
    background: transparent;
    border: none;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-xl);
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition-fast);
}

.btn-back:active,
.btn-share:active {
    background: var(--background);
    transform: scale(0.95);
}

.header-title {
    font-size: var(--font-lg);
    font-weight: var(--font-semibold);
    color: var(--text-primary);
}

/* ========== 话题信息 ========== */
.topic-info {
    margin-top: var(--header-height);
    background: var(--card-bg);
}

.topic-cover-large {
    position: relative;
    width: 100%;
    height: 200px;
    overflow: hidden;
}

.topic-cover-large img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.topic-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: var(--spacing-lg);
    background: linear-gradient(to top, rgba(0,0,0,0.7), transparent);
}

.topic-stats {
    display: flex;
    gap: var(--spacing-lg);
}

.topic-stats .stat {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: white;
    font-size: var(--font-sm);
}

.topic-stats .stat i {
    font-size: var(--font-md);
}

.topic-content {
    padding: var(--spacing-lg);
}

.topic-header-info {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-md);
}

.topic-title {
    flex: 1;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.topic-tag {
    font-size: var(--font-xl);
    font-weight: var(--font-bold);
    color: var(--primary-color);
}

.topic-badge {
    padding: 2px 8px;
    background: linear-gradient(135deg, #52c41a, #73d13d);
    color: white;
    font-size: var(--font-xs);
    border-radius: var(--radius-full);
    font-weight: var(--font-medium);
}

.btn-follow-topic {
    padding: 8px 16px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: var(--radius-full);
    font-size: var(--font-sm);
    font-weight: var(--font-medium);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    cursor: pointer;
    transition: var(--transition-fast);
}

.btn-follow-topic:active {
    transform: scale(0.95);
}

.topic-description {
    margin-bottom: var(--spacing-lg);
}

.topic-description p {
    font-size: var(--font-base);
    color: var(--text-regular);
    line-height: var(--line-height-relaxed);
    margin-bottom: var(--spacing-md);
}

.topic-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}

.topic-tags .tag {
    padding: 4px 12px;
    background: var(--background);
    color: var(--text-secondary);
    font-size: var(--font-xs);
    border-radius: var(--radius-full);
}

.topic-organizer {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--background);
    border-radius: var(--radius-lg);
}

.organizer-avatar {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    object-fit: cover;
}

.organizer-info {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.organizer-label {
    font-size: var(--font-xs);
    color: var(--text-secondary);
}

.organizer-name {
    font-size: var(--font-sm);
    font-weight: var(--font-medium);
    color: var(--text-primary);
}

.btn-follow-organizer {
    padding: 6px 16px;
    background: var(--card-bg);
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
    border-radius: var(--radius-full);
    font-size: var(--font-xs);
    font-weight: var(--font-medium);
    cursor: pointer;
    transition: var(--transition-fast);
}

.btn-follow-organizer:active {
    background: var(--primary-bg);
}

/* ========== 筛选栏 ========== */
.filter-bar {
    display: flex;
    align-items: center;
    justify-content: flex-start;
    padding: var(--spacing-sm) var(--spacing-lg);
    background: var(--card-bg);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
    margin-top: var(--spacing-sm);
    position: sticky;
    top: var(--header-height);
    z-index: calc(var(--z-sticky) - 1);
}

.filter-tabs {
    display: flex;
    gap: var(--spacing-lg);
}

.filter-tab {
    background: none;
    border: none;
    padding: 2px 0;
    font-size: var(--font-base);
    color: var(--text-secondary);
    cursor: pointer;
    position: relative;
    transition: var(--transition-fast);
}

.filter-tab.active {
    color: var(--text-primary);
    font-weight: var(--font-medium);
}

.filter-tab.active::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary-color);
}


/* ========== 作品网格 ========== */
.works-grid {
    padding: var(--spacing-sm);
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-sm);
    padding-bottom: var(--spacing-lg);
    background: var(--background);
}

.work-card {
    background: var(--card-bg);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: var(--transition-fast);
}

.work-card:active {
    transform: scale(0.98);
}

.work-image {
    position: relative;
    width: 100%;
}

.work-image img {
    width: 100%;
    height: auto;
    display: block;
}

.work-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: var(--spacing-sm);
    background: linear-gradient(to top, rgba(0,0,0,0.5), transparent);
    opacity: 0;
    transition: var(--transition-fast);
}

.work-card:hover .work-overlay {
    opacity: 1;
}

.work-likes {
    display: flex;
    align-items: center;
    gap: 4px;
    color: white;
    font-size: var(--font-sm);
    font-weight: var(--font-medium);
}

.work-likes i {
    font-size: var(--font-md);
}

.work-info {
    padding: var(--spacing-sm);
}

.work-author {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.work-author img {
    width: 24px;
    height: 24px;
    border-radius: var(--radius-full);
    object-fit: cover;
}

.work-author span {
    font-size: var(--font-xs);
    color: var(--text-regular);
}


/* ========== 响应式优化 ========== */
@media (min-width: 375px) {
    .works-grid {
        gap: var(--spacing-md);
        padding: var(--spacing-md);
    }
}

@media (min-width: 414px) {
    .topic-cover-large {
        height: 220px;
    }
}