yintai-company-home/src/layouts/Header.module.css

.header {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 1000;
  height: 7.5rem;
  width: 100%;

  font-family: Source Han Sans, Source Han Sans;
  font-weight: 700;
  font-size: 1.125rem;
  line-height: 1.625rem;
  text-align: left;
  font-style: normal;
  text-transform: none;

  /* transition: all 0.7s ease-in-out;
  transition-delay: 0.3s; */
}

.header::before {
  content: '';
  display: block;
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 0%;
  background: #fff;
  transition: height 0.5s ease-in-out;
}


.showDropPanel.header::before {
  height: 100%;
  transition: height 0.2s ease-in-out;
}

.whiteMode.header::before {
  height: 100%;
}

.whiteMode.header {
  /* background: rgba(255, 255, 255, 1); */
  box-shadow: 0 0 .625rem 0 rgba(255, 255, 255, 0.1);
  box-shadow: 0 0 .625rem 0 rgba(0, 0, 0, 0.2);
  transition-delay: none;
}

.keepNavDark.header::before {
  height: 7.5rem;
}

.whiteMode .navLink,
.showDropPanel .navLink,
.keepNavDark .navLink,
.keepNavDark .langTrigger,
.keepNavDark .searchBtn,
.keepNavDark svg {
  color: #222222;
  /* transition: color 0.3s ease-in-out; */
}
.keepNavDark svg path {
  fill: #222222;
}

.whiteMode,
.showDropPanel {
  .searchBtn {
    color: #222222;
  }

  .langTrigger {
    color: #222222;
  }

  svg,
  svg path {
    fill: #222222 !important;
  }
}

.activeNav .navLink {
  color: #14355C;
}

.headerInner {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  width: 100%;
  z-index: 99999;
}

.headerInner::after {
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  content: '';
  display: block;
  width: 95%;
  margin: 0 auto;
  box-sizing: border-box;
  height: .0625rem;
  background: #FFFFFF;
  transform: scaleX(0);
  transform-origin: 90% 0;
  /* 交点：左侧 85%，右侧 15%，从此点向左右展开 */
  transition: transform 1.5s ease-in-out;
}

.animate {
  &.headerInner::after {
    transform: scaleX(1);
  }

  .crossYline {
    height: 100%;
  }
}

.whiteMode,
.showDropPanel {
  .headerInner::after {
    transform: scaleX(0);
  }

  .crossYline {
    height: 0%;
  }
}

.logo {
  display: flex;
  flex-direction: column;
  font-weight: 600;
  line-height: 1.3;
}

.commonMode {
  .logo img {
    transition: filter 0.5s steps(1);
  }
}

.headerRight {
  display: flex;
  align-items: center;
  gap: 1.875rem;
  height: 100%;
}

.nav {
  display: flex;
  align-items: center;
  gap: 0;
  list-style: none;
  margin: 0;
  padding: 0;
  margin-right: 1.875rem;
}

.navItem {
  padding: 0 1.875rem;
}

.navLink {
  color: #fff;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
}

.navLink:hover {
  color: #14355C !important;
}

.navLink:hover {
  opacity: 0.9;
}


.actions {
  display: flex;
  height: 100%;
  align-items: center;
  gap: 1rem;
  margin-left: 1.875rem;
}

.crossYline {
  width: .0625rem;
  height: 0%;
  background: #FFFFFF;
  align-self: flex-end;
  /* 交点在最底部，从此点向上展开 */
  transform-origin: center bottom;
  /* 缩放从底部中心点展开 */
  transition: height 1s ease-in-out;
}

.langTrigger {
  display: flex;
  align-items: center;
  gap: .25rem;
  color: #fff;
  background: transparent;
  border: none;
  cursor: pointer;
  font-weight: bold;
}

.searchBtn {
  color: #fff;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: .25rem;
  display: flex;
  align-items: center;
  justify-content: center;
}


.dropPanel {
  position: absolute;
  top: 100%;
  left: 0;
  width: 100%;
  height: 0;
  background: rgba(255, 255, 255, 0.9);
  box-shadow: 0 0 .625rem 0 rgba(0, 0, 0, 0.1);
  padding: 0;
  z-index: 1000;
  overflow: hidden;
  transition: height 0.5s ease-in-out, padding-top 0.5s ease-in-out;
  /* transition-delay: 0.45s; */

  &.visible {
    height: 23.75rem;
    padding-top: 1.25rem;

  }
}

.dropPanelContent {
  display: inline-flex;
  flex-direction: column;
  text-align: center;
  transform: translateX(-50%);
}

.dropPanelLink {
  font-weight: 400;
  font-size: 1.125rem;
  line-height: 3.125rem;
  color: #222222;
  text-decoration: none;

  &:hover {
    color: #14355C;
  }
}

@media (max-width: 64rem) {
  .header {
    height: 5.5rem;
  }

  .headerInner::after {
    left: 1.5rem;
    width: calc(100% - 3rem);
  }

  .navItem {
    padding: 0 1rem;
  }

  .headerRight {
    gap: 1rem;
  }

  .nav {
    margin-right: 1rem;
  }

  .actions {
    margin-left: 1rem;
  }
}

/* Hamburger button - hidden on desktop */
.hamburger {
  display: none;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 0.25rem;
  position: relative;
  z-index: 1;
  width: 2.5rem;
  height: 2.5rem;
}

.hamburgerBar {
  display: block;
  width: 1.5rem;
  height: 2px;
  background: #fff;
  position: relative;
  transition: background 0.3s;
}

.hamburgerBar::before,
.hamburgerBar::after {
  content: '';
  display: block;
  width: 1.5rem;
  height: 2px;
  background: #fff;
  position: absolute;
  left: 0;
  transition: transform 0.3s, top 0.3s;
}

.hamburgerBar::before {
  top: -0.45rem;
}

.hamburgerBar::after {
  top: 0.45rem;
}

.hamburgerOpen .hamburgerBar {
  background: transparent;
}

.hamburgerOpen .hamburgerBar::before {
  top: 0;
  transform: rotate(45deg);
  background: #222;
}

.hamburgerOpen .hamburgerBar::after {
  top: 0;
  transform: rotate(-45deg);
  background: #222;
}

.whiteMode .hamburgerBar,
.whiteMode .hamburgerBar::before,
.whiteMode .hamburgerBar::after,
.keepNavDark .hamburgerBar,
.keepNavDark .hamburgerBar::before,
.keepNavDark .hamburgerBar::after {
  background: #222;
}

.hamburgerOpen .hamburgerBar {
  background: transparent !important;
}

/* Mobile drawer */
.mobileDrawer {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100vh;
  height: 100dvh;
  background: #fff;
  z-index: 999;
  padding-top: 4rem;
  overflow-y: auto;
  transform: translateX(100%);
  transition: transform 0.35s ease;
}

.mobileDrawerOpen {
  transform: translateX(0);
}

.mobileNavList {
  list-style: none;
  margin: 0;
  padding: 1.5rem 1.25rem;
  margin-top: 3rem;
}

.mobileNavItem {
  border-bottom: 1px solid #eee;
}

.mobileNavLink {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 0;
  font-size: 1.125rem;
  font-weight: 600;
  color: #222;
  text-decoration: none;
  cursor: pointer;
}

.mobileNavArrow {
  font-size: 0.75rem;
  transition: transform 0.3s;
  color: #999;
}

.mobileNavArrowOpen {
  transform: rotate(90deg);
}

.mobileSubList {
  list-style: none;
  margin: 0;
  padding: 0 0 0.5rem 1rem;
}

.mobileSubLink {
  display: block;
  padding: 0.625rem 0;
  font-size: 1rem;
  font-weight: 400;
  color: #555;
  text-decoration: none;
}

.mobileSubLink:active {
  color: #14355C;
}

.mobileDrawerActions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.5rem 1.25rem;
  border-top: 1px solid #eee;
  margin-top: 1rem;
}

.mobileDrawerActions .searchBtn {
  color: #222;
}

.mobileDrawerActions .searchBtn svg,
.mobileDrawerActions .searchBtn svg path {
  fill: #222 !important;
}

.mobileDrawerActions .langTrigger {
  color: #222;
}

@media (max-width: 48rem) {
  .header {
    height: 8rem;
    width: 100vw;
  }

  .headerInner::after {
    left: 1rem;
    width: calc(100% - 2rem);
  }

  .nav,
  .actions,
  .crossYline {
    display: none;
  }

  .hamburger {
    display: flex;
  }

  .dropPanel {
    display: none;
  }

}