*{margin:0;padding:0;}
body{ min-height: 100px; font-family: Arial; font-weight: bold; }
ul{list-style: none}

.mainBox{min-height:100px;width:100%;}
.firstBox{min-height:200px;width:80%;margin:10px auto;position:relative}
.menuBox{height:80px;background-color: #ccc;position: relative;}
.menuBox ul{background-color:#fff;width:100%;height:80px;display: flex;justify-content: flex-start;align-items: center;}
.menuBox ul li{ height: 80px; width: 33.333%; border-bottom: 1px solid #ccc; background-color: #DFDFDF; text-align: center; line-height: 80px; font-weight: bold; font-size: 30px; }
.menuBox ul li.liactive{border-bottom:none; background-color: #3B3B3B; color: #fff}
.contentBox{height:300px;width:100%;background-color: #fff;position:absolute;overflow: hidden;position:relative}
.contentBox ul{height:300px;width:300%;display: flex;justify-content: center;align-items: center;margin-top:10px;position:absolute;left:0;top:0;transition: all 0.5s ease}
.contentBox ul li{height:300px;width:100%;}
.contentBox li{ line-height: 300px; text-align: center; color: #FFFFFF; font-size: 80px; }
.green{background-color: green}
.red{background-color: #005EDD}
.yellow{background-color: #833030}