.os_t_syk4 {
  padding: 20px;
}

.t_yiqih2 h2 {
  text-align: center;
  font-size: 24px;
  margin-bottom: 30px;
}

ul.f-cb {
  list-style: none;
  padding: 0;
  margin: 0 auto;
  max-width: 1200px;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
}

ul.f-cb li {
  flex: 0 0 calc(25% - 20px);
  box-sizing: border-box;
  margin-bottom: 40px;
  background: #f9f9f9;
  padding: 20px;
  border-radius: 8px;
  text-align: center;
}

ul.f-cb li img {
  max-width: 80px;
  height: auto;
  margin-bottom: 15px;
}

ul.f-cb li .os_title,
ul.f-cb li .title {
  font-size: 18px;
  font-weight: bold;
  margin-bottom: 10px;
}

ul.f-cb li .os_detaile,
ul.f-cb li .detaile {
  font-size: 14px;
  color: #666;
  line-height: 1.6;
}

@media (max-width: 992px) {
  ul.f-cb li {
    flex: 0 0 calc(33.33% - 20px);
  }
}

@media (max-width: 768px) {
  ul.f-cb {
    justify-content: center;
  }
  ul.f-cb li {
    flex: 0 0 calc(50% - 20px);
  }
}

@media (max-width: 480px) {
  ul.f-cb li {
    flex: 0 0 100%;
  }
}