/* 卡片组件样式 */
.card {
    background: white;
    border-radius: 12px;
    padding: 20px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
    cursor: pointer;
    border: 1px solid #f0f0f0;
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(0,0,0,0.15);
    border-color: #1890ff;
}

/* AI应用卡片 */
.app-card {
    display: flex;
    align-items: flex-start;
    gap: 16px;
}

.app-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 20px;
    font-weight: 600;
    flex-shrink: 0;
}

.app-content {
    flex: 1;
    min-width: 0;
}

.app-title {
    font-size: 16px;
    font-weight: 600;
    color: #333;
    margin-bottom: 8px;
    display: -webkit-box;
    -webkit-line-clamp: 1;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.app-description {
    font-size: 14px;
    color: #666;
    line-height: 1.5;
    margin-bottom: 12px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.app-meta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 12px;
    color: #999;
}

.app-tags {
    display: flex;
    gap: 8px;
}

.app-tag {
    background: #f0f0f0;
    color: #666;
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 11px;
}

.app-stats {
    display: flex;
    align-items: center;
    gap: 16px;
}

.stat-item {
    display: flex;
    align-items: center;
    gap: 4px;
}

.stat-icon {
    width: 14px;
    height: 14px;
}

/* AI工具卡片 */
.tool-card {
    text-align: center;
    padding: 32px 20px;
}

.tool-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 16px;
    background: linear-gradient(135deg, #52c41a 0%, #73d13d 100%);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 24px;
}

.tool-title {
    font-size: 18px;
    font-weight: 600;
    color: #333;
    margin-bottom: 8px;
}

.tool-description {
    font-size: 14px;
    color: #666;
    margin-bottom: 20px;
    line-height: 1.5;
}

.tool-action {
    background: #1890ff;
    color: white;
    border: none;
    padding: 8px 24px;
    border-radius: 6px;
    font-size: 14px;
    cursor: pointer;
    transition: background-color 0.3s;
}

.tool-action:hover {
    background: #40a9ff;
}

/* AI课程卡片 */
.course-card {
    position: relative;
    overflow: hidden;
}

.course-badge {
    position: absolute;
    top: 12px;
    right: 12px;
    background: #ff4d4f;
    color: white;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 12px;
    font-weight: 600;
    z-index: 1;
}

.course-badge.hot {
    background: #ff4d4f;
}

.course-badge.new {
    background: #52c41a;
}

.course-badge.top {
    background: #fa8c16;
}

.course-image {
    width: 100%;
    height: 160px;
    background: linear-gradient(135deg, #ffecd2 0%, #fcb69f 100%);
    border-radius: 8px;
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 48px;
    color: rgba(255,255,255,0.8);
}

.course-content {
    padding: 0 4px;
}

.course-title {
    font-size: 16px;
    font-weight: 600;
    color: #333;
    margin-bottom: 8px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    line-height: 1.4;
}

.course-description {
    font-size: 14px;
    color: #666;
    margin-bottom: 16px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    line-height: 1.5;
}

.course-action {
    background: #1890ff;
    color: white;
    border: none;
    padding: 8px 20px;
    border-radius: 6px;
    font-size: 14px;
    cursor: pointer;
    transition: background-color 0.3s;
    width: 100%;
}

.course-action:hover {
    background: #40a9ff;
}

/* 加载状态 */
.loading {
    text-align: center;
    padding: 40px;
    color: #666;
}

.loading::after {
    content: '';
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid #f3f3f3;
    border-top: 2px solid #1890ff;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-left: 8px;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* 空状态 */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: #999;
}

.empty-icon {
    font-size: 48px;
    margin-bottom: 16px;
    opacity: 0.5;
}

.empty-text {
    font-size: 16px;
    margin-bottom: 8px;
}

.empty-description {
    font-size: 14px;
    color: #ccc;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .app-card {
        flex-direction: column;
        text-align: center;
    }

    .app-meta {
        flex-direction: column;
        gap: 8px;
        align-items: center;
    }

    .tool-card {
        padding: 24px 16px;
    }

    .course-image {
        height: 120px;
        font-size: 36px;
    }
}