/* ========================================
   活动中心页面样式
   ======================================== */

/* ========== 筛选区域 ========== */
.activity-filter {
    background-color: var(--white);
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-lg) 0;
    position: sticky;
    top: 72px;
    z-index: 100;
}

/* ========== 精选活动 ========== */
.featured-activities {
    padding: var(--spacing-3xl) 0;
    background-color: var(--bg-light);
}

.featured-activities .section-header {
    margin-bottom: var(--spacing-xl);
}

.featured-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-xl);
}

/* ========== 活动卡片 ========== */
.activity-card {
    background-color: var(--white);
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all 0.3s ease;
}

.activity-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.activity-card.ended {
    opacity: 0.6;
}

.activity-card.ended:hover {
    transform: none;
    box-shadow: var(--shadow-sm);
}

/* 精选活动大卡片 */
.activity-card.featured {
    display: flex;
}

.activity-card.featured .activity-image {
    width: 300px;
    flex-shrink: 0;
}

.activity-image {
    position: relative;
}

.image-placeholder {
    width: 100%;
    height: 200px;
    background: linear-gradient(135deg, var(--bg-blue) 0%, var(--primary-blue) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
}

.image-placeholder span {
    font-size: 64px;
}

.image-placeholder.small {
    height: 140px;
}

.image-placeholder.small span {
    font-size: 48px;
}

.activity-date-badge {
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    background-color: var(--white);
    border-radius: var(--radius-md);
    padding: var(--spacing-sm) var(--spacing-md);
    text-align: center;
    box-shadow: var(--shadow-md);
}

.activity-date-badge.small {
    padding: 4px 8px;
}

.date-day {
    display: block;
    font-size: 24px;
    font-weight: 700;
    color: var(--primary-blue);
    line-height: 1;
}

.activity-date-badge.small .date-day {
    font-size: 18px;
}

.date-month {
    display: block;
    font-size: 12px;
    color: var(--text-gray);
    line-height: 1;
}

.activity-content {
    padding: var(--spacing-lg);
    display: flex;
    flex-direction: column;
    flex: 1;
}

.activity-tags {
    display: flex;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-sm);
}

.activity-tag {
    display: inline-flex;
    padding: 4px 10px;
    font-size: 12px;
    font-weight: 500;
    border-radius: var(--radius-sm);
}

.tag-training { background-color: #FEF3C7; color: #92400E; }
.tag-salon { background-color: #DBEAFE; color: #1E40AF; }
.tag-meetup { background-color: #D1FAE5; color: #065F46; }
.tag-lecture { background-color: #EDE9FE; color: #5B21B6; }
.tag-hot { background-color: var(--primary-red); color: var(--white); }
.tag-online { background-color: #E0E7FF; color: #3730A3; }
.tag-ended { background-color: var(--text-light); color: var(--white); }

.activity-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: var(--spacing-sm);
    line-height: 1.4;
}

.activity-desc {
    font-size: 14px;
    color: var(--text-gray);
    line-height: 1.6;
    margin-bottom: var(--spacing-md);
}

.activity-meta {
    margin-bottom: var(--spacing-lg);
}

.activity-meta.compact {
    margin-bottom: var(--spacing-md);
}

.meta-row {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 14px;
    color: var(--text-gray);
    margin-bottom: var(--spacing-xs);
}

.meta-icon {
    font-size: 16px;
}

.activity-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: auto;
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--border-color);
}

.activity-host {
    font-size: 13px;
    color: var(--text-light);
}

.host-label {
    color: var(--text-light);
}

.host-name {
    color: var(--text-dark);
    font-weight: 500;
}

.btn-sm {
    padding: 6px 16px;
    font-size: 13px;
}

.btn-disabled {
    background-color: var(--border-color);
    border-color: var(--border-color);
    color: var(--text-light);
    cursor: not-allowed;
}

/* ========== 活动列表 ========== */
.activity-list {
    padding: var(--spacing-3xl) 0;
    background-color: var(--white);
}

.activity-list .section-header {
    margin-bottom: var(--spacing-xl);
}

.activity-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
}

/* 普通活动卡片 */
.activity-grid .activity-card .activity-image {
    width: 100%;
}

/* ========== 活动须知 ========== */
.activity-tips {
    padding: var(--spacing-3xl) 0;
    background-color: var(--bg-light);
}

.activity-tips .section-title {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
}

.tips-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-lg);
}

.tip-card {
    background-color: var(--white);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    text-align: center;
}

.tip-icon {
    font-size: 48px;
    margin-bottom: var(--spacing-md);
}

.tip-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-dark);
    margin-bottom: var(--spacing-sm);
}

.tip-desc {
    font-size: 14px;
    color: var(--text-gray);
    line-height: 1.6;
}

/* ========== 响应式 ========== */
@media (max-width: 1200px) {
    .activity-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .tips-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 992px) {
    .activity-card.featured {
        flex-direction: column;
    }
    
    .activity-card.featured .activity-image {
        width: 100%;
    }
    
    .activity-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .page-header {
        padding: 100px 0 32px;
    }
    
    .page-title {
        font-size: 28px;
    }
    
    .filter-bar {
        flex-direction: column;
        align-items: stretch;
    }
    
    .filter-options {
        flex-direction: column;
    }
    
    .filter-group {
        width: 100%;
    }
    
    .filter-group select {
        width: 100%;
    }
    
    .tips-grid {
        grid-template-columns: 1fr;
    }
}