html {
  font-size: 1vw;
}
.header-container {
  position: -webkit-sticky; /* Safari */
  position: sticky;
  top: 0;
  left: 0;
  width: 100rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: #f2f2f2;
  padding: 1rem 9rem;
  box-sizing: border-box;
  z-index: 10;
}
/* 如果 .header-container 仍被外层容器影响，将 sticky 应用于 header 元素本身 */
header {
  position: -webkit-sticky;
  position: sticky;
  top: 0;
  z-index: 9999;
  background: #f2f2f2;
}
.header-logo {
  display: flex;
  align-items: center;
  height: 3.75rem;
}
.header-logo-img {
  height: 3.75rem;
  width: auto;
  display: block;
}
.header-language {
  position: absolute;
  left: 94rem;
  top: 1rem;
  width: 3.75rem;
  height: 3.75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  user-select: none; /* 禁止文本选择 */
  z-index: 10000;
}

/* 圆形样式 */
.header-language-circle {
  position: absolute;
  width: 1.5rem !important;
  height: 1.5rem !important;
  border-radius: 50% !important;

  background: var(--theme-color1);
  z-index: 1;
}

/* 文字样式 */
.header-language-text {
  position: relative;
  color: white;
  font-size: 0.7rem;
  z-index: 2;
  text-align: center;

  width: auto;
  box-sizing: border-box;
  cursor: pointer;
}
.header-menu ul {
  list-style: none;
  margin: 0 0rem 0 0;
  padding: 0;
  display: flex;
  gap: 2rem;
  grid-gap: 2rem;
}
.header-menu a {
  /* 去除下划线 */
  text-decoration: none;
  color: #333;
}
.header-menu ul ul a {
  color: #fff;
}
.header-menu > ul > li {
  position: relative;
  font-size: 1.1rem;
  color: #333;
  cursor: pointer;
  transition: color 0.2s;
  font-weight: normal;
  letter-spacing: 0.1rem;
  padding: 0.5rem 0rem;
}

/* .header-menu > ul > li::after {
  content: "";
  display: block;
  height: 0.1875rem;
  width: 80%;
  background: var(--theme-color1);
  margin: 0.375rem auto 0 auto;
  border-radius: 0.125rem;
  opacity: 0;
  transition: opacity 0.2s;
}
.header-menu > ul > li:hover::after {
  opacity: 1;
}
.header-menu > ul > li:hover {
  color: var(--theme-color1);
} */
.header-menu ul ul {
  display: none;
  position: absolute;
  left: 50%;
  top: 100%;
  transform: translateX(-50%);
  background: var(--theme-color1);
  box-shadow: 0 0.125rem 0.5rem rgba(0, 0, 0, 0.08);
  border-radius: 0.25rem;
  min-width: 7.5rem;
  z-index: 10;
  flex-direction: column;
  gap: 0;
}
.header-menu > ul > li:hover > ul {
  display: flex;
}
.header-menu ul ul li {
  padding: 0.5rem 1rem;
  color: #fff;
  white-space: nowrap;
  font-size: 1rem;
  font-weight: 400;
  transition: background 0.2s, color 0.2s;
  text-align: center;
  position: relative;
}

.header-menu ul ul ul {
  display: none;
  position: absolute;
  left: 150%;
  top: 0;
  background: var(--theme-color1);
  box-shadow: 0 0.125rem 0.5rem rgba(0, 0, 0, 0.08);
  border-radius: 0.25rem;
  min-width: 7.5rem;
  z-index: 10;
}

.header-menu ul ul li:hover > ul {
  display: flex;
  flex-direction: column;
}
/* 学生培养菜单下的二级标题文字为红色 */
/* .header-menu > ul > li:nth-child(3) > ul > li {
  color: #fb2f2f;
} */
.header-menu ul ul li:hover {
  /* background: #0078d7; */
  background: var(--theme-color1);
  color: #fff;
}