/* 底部白色 */
.footer {
    background-color: #fff;
}




/* ----------------------免费内容板块---------------------- */

/* 标题 */
.title_video {
    margin-top: 40px;
    margin-bottom: 20px;
    width: 90%;
}

.title_video h2 {
    font-size: 36px;
    font-weight: 700;
    color: #000;
}

/* 内容 */
.past_video {
  display: flex;
  justify-content: flex-start;
  align-content: flex-start;
  flex-wrap: wrap;
  min-height: 400px;
  width: 90%;
}
.past_video a {
    width: calc(25% - 11.25px);
    margin-right: 15px;
    margin-bottom: 30px;
    text-decoration: none;
}

/* 统一处理右边距 */
.past_video a:nth-child(4n) {
    margin-right: 0;
}

@media (max-width: 1068px) {
    .past_video a {
        width: calc(33.333% - 10px);
    }
    
    .past_video a:nth-child(4n) {
        margin-right: 15px;  /* 重置四列布局的右边距 */
    }
    
    .past_video a:nth-child(3n) {
        margin-right: 0;
    }
    .title_video h2 {
        font-size: 32px;
    }
}

@media (max-width: 734px) {
    .past_video a {
        width: calc(50% - 7.5px);
    }
    
    .past_video a:nth-child(3n) {
        margin-right: 15px;  /* 重置三列布局的右边距 */
    }
    
    .past_video a:nth-child(2n) {
        margin-right: 0;
    }
    .title_video h2 {
        font-size: 28px;
    }
}

.past_video a img {
    width: 100%;
}

.past_video a h3 {
    font-size: 15px;
    font-weight: 700;
    color: #000;
}

.past_video a h3:hover {
    color: #555;
    text-decoration: none;
}

.past_video a span,
.past_video a p {
    display: inline-block;
    font-size: 12px;
    color: #999;
    margin-top: 10px;
}