ant-design/site/theme/static/header.less

@header-height: 80px;

#header {
  transition: opacity 0.5s;
  background: #fff;
  border-bottom: 1px solid #eee;
  height: @header-height;
  margin-bottom: 24px;
  padding: 0 4%;
  width: 100%;

  &.home-nav-bottom {
    background: rgba(255, 255, 255, 0.9);
    border-bottom-color: #EBEDEE;
    .search {
      border-left-color: #EBEDEE;
    }
    a {
      color: #666;
    }
  }
}

#logo {
  float: left;
  height: 80px;
  line-height: 80px;
}

#logo img {
  height: 80px;
  line-height: 80px;
  width: 40px;
  margin-right: 8px;
}

#logo span {
  float: right;
  font-size: 16px;
  font-family: 'Raleway', 'Hiragino Sans GB', sans-serif;
  height: 80px;
  line-height: 80px;
  text-transform: uppercase;
}

#search-box {
  border-left: 1px solid #EBEDEE;
  float: left;
  height: 22px;
  line-height: 22px;
  padding-left: 30px;
  margin: 29px auto 0;
}

#search-box .ant-select {
  font-size: 14px;
  margin-top: -3px;
  width: 230px;
}

#search-box .ant-select-selection {
  border: 0;
  box-shadow: none;
}

.lang {
  float: right;
  margin-top: 29px;
  margin-left: 12px;
}

#nav {
  border: 0;
  float: right;
  font-size: 14px;
  font-family: Lato, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", SimSun, sans-serif;
}

#nav li {
  height: @header-height;
  line-height: @header-height;
  min-width: 72px;
  text-align: center;
  border-bottom-width: 3px;

  &.ant-menu-item-selected a {
    color: @primary-color;
    font-weight: bold;
  }
}

.component-select {
  &.ant-select-dropdown {
    border: 0;
    border-radius: 0;
    box-shadow: 0 0 8px rgba(0,0,0,0.25);
    font-size: 14px;
  }
  .ant-select-dropdown-menu {
    max-height: 200px;
  }
  .ant-select-dropdown-menu-item {
    border-radius: 0 !important;
  }
  .ant-component-decs {
    font-size: 12px;
    position: absolute;
    top: 9px;
    color: #aaa;
    right: 16px;
  }
}