.tabs {
    display: flex;
    justify-content: space-between;
    margin-bottom: 20px;
  }

.tab {
flex-grow: 1; /* 使每个标签平均分配可用空间 */
text-align: center; /* 文字居中 */
cursor: pointer;
padding: 10px 20px;
margin: 0 10px;
background-color: #f0f0f0;
border: 2px solid transparent;
border-radius: 5px;
transition: background-color 0.3s, border-color 0.3s;
}

.tab:hover {
background-color: #e0e0e0;
}

.tab.active {
background-color: #fff;
border-color: #007bff;
color: #007bff;
}

.thumbnails {
  width: 90%;
  overflow: hidden;
  margin-top: 20px;
  margin-bottom: 5px;
  margin-left: auto;
  margin-right: auto;
}

.thumbnail-btn {
  border: none;
  cursor: pointer;
  outline: none;
  background-color: #fff;
  padding-bottom: 8px;
  border-radius: 10px;
}

.thumbnail-btn:hover   {
  background-color: #eaeaea;
}

.active-btn   {
  background-color: #d9e8ec;
}

.thumbnail-row {
  display: flex;
  overflow-x: scroll;
  scroll-behavior: smooth;
  width: 88%;
  margin-left: auto;
  margin-right: auto;
  float: left;
}

.thumbnail-col {
  width: 22%;
  flex: 1 0 22%;
}

.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: #ccc;
  -webkit-transition: .2s;
  transition: .2s;
  border-radius: 34px;
}

.slider:before {
  position: absolute;
  content: "";
  height: 26px;
  width: 26px;
  left: 4px;
  bottom: 4px;
  background-color: white;
  -webkit-transition: .2s;
  transition: .2s;
  border-radius: 50%;
}

input:checked + .slider {
  background-color: #2196F3;
}

input:focus + .slider {
  box-shadow: 0 0 1px #2196F3;
}

input:checked + .slider:before {
  -webkit-transform: translateX(36px);
  -ms-transform: translateX(36px);
  transform: translateX(36px);
}

.slide-arrow {
  display: flex;
  top: 0;
  bottom: 0;
  margin-top: 40px;
  height: 4rem;
  background-color: #6dbdff;
  border: none;
  width: 5%;
  font-size: 2.5rem;
  padding: 0;
  cursor: pointer;
  opacity: 1.0;
  transition: color 100ms;
  justify-content: center;
}

.slide-arrow:hover,
.slide-arrow:focus {
  background-color: #2196F3;
  opacity: 1;
}

#slide-arrow-prev {
  float: left;
  left: 0;
  margin-right: 1%;
  border-radius: 2rem 2rem 2rem 2rem;
}

#slide-arrow-next {
  float: right;
  right: 0;
  margin-left: 1%;
  border-radius: 2rem 2rem 2rem 2rem;
}

#main-video {
  width: 90%;
  margin-top: 0px;
  margin-bottom: 10px;
  border-radius: 15px;
}