:root {
  --teal-950: #123f43;
  --teal-800: #185b5c;
  --teal-700: #257572;
  --teal-500: #579995;
  --teal-200: #c9e1dc;
  --teal-100: #eaf5f2;
  --teal-50: #f4faf8;
  --gold: #ae8648;
  --ink-soft: #627879;
  --paper: #fff;
  --line: rgba(25, 91, 92, 0.14);
  --shadow: 0 20px 54px rgba(19, 66, 67, 0.09);
  --page-gutter: clamp(24px, 4.5vw, 72px);
  --ui-font: "DM Sans", "Avenir Next", "Helvetica Neue", sans-serif;
  --editorial-font: "Newsreader", Georgia, serif;
  --chinese-font: "Noto Sans SC", "PingFang SC", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  position: relative;
  margin: 0;
  min-width: 320px;
  color: var(--teal-950);
  background:
    radial-gradient(circle at 10% 0, rgba(190, 224, 215, 0.34), transparent 28rem),
    linear-gradient(180deg, #fbfdfc, #f2f8f6 48rem);
  font-family: var(--ui-font);
  font-size: 16px;
  line-height: 1.5;
}

.homepage-intro {
  position: relative;
  isolation: isolate;
}

.homepage-intro::before {
  position: absolute;
  z-index: -1;
  top: -100px;
  bottom: -18px;
  left: 50%;
  width: 100vw;
  content: "";
  pointer-events: none;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.02), rgba(255, 255, 255, 0.08)),
    url("assets/brand/homepage-landscape-west-lake-full-v1.webp") center bottom / cover no-repeat;
  transform: translateX(-50%);
}

button,
a {
  font: inherit;
}

a:focus-visible,
button:focus-visible {
  outline: 3px solid rgba(37, 117, 114, 0.28);
  outline-offset: 3px;
}

.page-shell,
.site-footer {
  width: auto;
  margin-inline: var(--page-gutter);
}

.site-header {
  position: sticky;
  z-index: 20;
  top: 0;
  display: grid;
  grid-template-columns: minmax(200px, 1fr) auto minmax(200px, 1fr);
  width: 100%;
  min-height: 82px;
  margin: 0;
  padding: 9px clamp(20px, 4.5vw, 72px);
  align-items: center;
  border: 0;
  border-bottom: 1px solid transparent;
  border-radius: 0;
  background: transparent;
  box-shadow: none;
  backdrop-filter: none;
  transition: background-color 180ms ease, border-color 180ms ease, box-shadow 180ms ease;
}

.site-header.is-scrolled {
  border-bottom-color: rgba(25, 91, 92, 0.12);
  background: rgba(249, 252, 251, 0.92);
  box-shadow: 0 8px 24px rgba(19, 66, 67, 0.06);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  width: max-content;
  align-items: center;
  gap: 10px;
  color: var(--teal-950);
  text-decoration: none;
}

.brand img {
  width: 56px;
  height: 56px;
  object-fit: contain;
}

.brand-wordmark {
  display: inline-flex;
  align-items: baseline;
  white-space: nowrap;
}

.brand .brand-nihao,
.brand .brand-world {
  font-family: "Lora", Georgia, serif;
  font-size: 1.86rem;
  font-weight: 700;
  letter-spacing: -0.045em;
  line-height: 1;
}

.brand .brand-nihao {
  color: var(--teal-800);
  font-style: italic;
  font-weight: 700;
  letter-spacing: -0.035em;
  transform: scaleX(1.035);
  transform-origin: left center;
  -webkit-text-stroke: 0.32px currentColor;
}

.brand .brand-world {
  margin-left: 0.1em;
  color: #aa8247;
  font-style: normal;
}

.primary-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.primary-nav a,
.about-menu > summary {
  border-radius: 6px;
  color: #335f60;
  font-size: 1rem;
  font-weight: 600;
  line-height: 1;
  text-decoration: none;
  transition: color 160ms ease, background 160ms ease, transform 160ms ease;
}

.primary-nav a {
  padding: 15px 22px;
  font-size: 1.12rem;
  font-weight: 700;
  letter-spacing: -0.015em;
}

.primary-nav a:hover,
.primary-nav a.is-current {
  color: var(--teal-800);
  background: var(--teal-100);
}

.about-menu {
  position: relative;
  justify-self: end;
}

.about-menu > summary {
  padding: 11px 5px;
  border: 0;
  border-bottom: 1px solid rgba(25, 91, 92, 0.28);
  cursor: pointer;
  list-style: none;
}

.about-menu > summary::-webkit-details-marker {
  display: none;
}

.about-menu > summary:hover,
.about-menu[open] > summary {
  color: #fff;
  background: var(--teal-800);
  transform: translateY(-1px);
}

.about-popover {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  display: grid;
  width: 270px;
  padding: 7px;
  gap: 2px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
  box-shadow: 0 18px 46px rgba(19, 66, 67, 0.14);
}

.about-popover a {
  display: grid;
  padding: 10px 11px;
  gap: 1px;
  border-radius: 6px;
  color: var(--teal-950);
  text-decoration: none;
}

.about-popover a:hover {
  background: var(--teal-50);
}

.about-popover strong {
  font-size: 0.9rem;
  line-height: 1.25;
}

.about-popover small {
  color: var(--ink-soft);
  font-size: 0.73rem;
  line-height: 1.35;
}

.menu-toggle {
  position: relative;
  display: none;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 0;
  border-radius: 8px;
  background: transparent;
  cursor: pointer;
  transition: background-color 160ms ease;
}

.menu-toggle:hover {
  background: rgba(234, 245, 242, 0.72);
}

.menu-toggle:focus-visible {
  outline: 2px solid rgba(37, 117, 114, 0.48);
  outline-offset: 2px;
}

.menu-toggle span {
  position: absolute;
  left: 10px;
  display: block;
  width: 24px;
  height: 2px;
  margin: 0;
  border-radius: 2px;
  background: var(--teal-800);
  transition: top 180ms ease, opacity 140ms ease, transform 180ms ease;
}

.menu-toggle span:nth-child(1) {
  top: 13px;
}

.menu-toggle span:nth-child(2) {
  top: 21px;
}

.menu-toggle span:nth-child(3) {
  top: 29px;
}

.menu-toggle[aria-expanded="true"] span:nth-child(1) {
  top: 21px;
  transform: rotate(45deg);
}

.menu-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0.35);
}

.menu-toggle[aria-expanded="true"] span:nth-child(3) {
  top: 21px;
  transform: rotate(-45deg);
}

.page-shell {
  position: relative;
  z-index: 1;
  padding: 4px 0 14px;
}

.hero {
  min-height: 94px;
  border: 0;
  border-radius: 0;
  background: transparent;
  box-shadow: none;
}

.hero-copy {
  display: grid;
  padding: 13px 24px 22px;
  justify-items: center;
  text-align: center;
}

.hero h1 {
  margin: 0;
  color: var(--teal-800);
  font-family: var(--editorial-font);
  font-size: clamp(1.95rem, 3.25vw, 2.85rem);
  font-weight: 600;
  letter-spacing: -0.05em;
  line-height: 0.96;
}

.hero h1 a {
  position: relative;
  display: flex;
  padding-bottom: 5px;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0 0.22em;
  color: inherit;
  text-decoration: none;
}

.hero h1 a::after {
  position: absolute;
  right: 0;
  bottom: 0;
  left: 0;
  height: 1px;
  content: "";
  background: rgba(37, 117, 114, 0.55);
  transform: scaleX(0);
  transform-origin: center;
  transition: transform 180ms ease;
}

.hero h1 a:hover::after,
.hero h1 a:focus-visible::after {
  transform: scaleX(1);
}

.hero h1 a:hover span {
  color: var(--teal-800);
}

.hero h1 span:last-child {
  color: var(--teal-700);
}

.hero h1 a span {
  transition: color 180ms ease;
}

.hero h1 a:hover span:last-child {
  color: var(--teal-800);
}

.pathways {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  width: 100%;
  gap: 10px;
  margin: 0;
}

.pathway-card {
  --card-bg: #f8e9e6;
  --card-accent: #8d3e3d;
  --arrow-bg: #f1d2cd;
  display: grid;
  overflow: hidden;
  grid-template-columns: minmax(165px, 43%) minmax(0, 1fr) 34px;
  min-height: 172px;
  padding: 0 13px 0 0;
  align-items: center;
  gap: 12px;
  border: 1px solid rgba(32, 111, 107, 0.16);
  border-radius: 9px;
  color: var(--teal-950);
  background: var(--card-bg);
  box-shadow: 0 8px 22px rgba(19, 66, 67, 0.08);
  text-decoration: none;
  transition: transform 180ms ease, border-color 180ms ease, box-shadow 180ms ease;
}

.pathway-card:hover {
  border-color: rgba(32, 111, 107, 0.42);
  box-shadow: 0 18px 40px rgba(19, 66, 67, 0.14);
  transform: translateY(-4px);
}

.pathway-books {
  --card-bg: #e7f1f7;
  --card-accent: #285b76;
  --arrow-bg: #d3e4ee;
}

.pathway-culture {
  --card-bg: #f3efdc;
  --card-accent: #4c625a;
  --arrow-bg: #e5ddbd;
  border-color: rgba(174, 134, 72, 0.2);
}

.pathway-visual {
  position: relative;
  width: 100%;
  aspect-ratio: 3 / 2;
  align-self: center;
  overflow: hidden;
  background: var(--card-bg);
}

.pathway-visual::after {
  position: absolute;
  z-index: 1;
  inset: 0;
  content: "";
  pointer-events: none;
  background:
    linear-gradient(
      90deg,
      var(--card-bg) 0%,
      transparent 7%,
      transparent 70%,
      var(--card-bg) 100%
    ),
    linear-gradient(
      180deg,
      var(--card-bg) 0%,
      transparent 12%,
      transparent 88%,
      var(--card-bg) 100%
    );
}

.pathway-visual img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  mix-blend-mode: multiply;
}

.pathway-learn .pathway-visual img {
  object-position: 48% center;
}

.pathway-books .pathway-visual img {
  object-position: 50% center;
}

.pathway-culture .pathway-visual img {
  object-position: 51% center;
}

.pathway-copy {
  display: grid;
  gap: 5px;
  min-width: 0;
}

.pathway-copy strong {
  color: var(--card-accent);
  font-family: var(--editorial-font);
  font-size: 1.5rem;
  font-weight: 600;
  letter-spacing: -0.025em;
  line-height: 1.08;
}

.pathway-copy small {
  color: #536d6f;
  font-size: 1rem;
  line-height: 1.34;
}

.pathway-copy > span {
  margin-top: 6px;
  color: var(--card-accent);
  font-size: 0.9rem;
  font-weight: 700;
  line-height: 1.3;
}

.pathway-arrow {
  display: grid;
  width: 31px;
  height: 31px;
  place-items: center;
  border: 0;
  border-radius: 50%;
  color: #fff;
  background: var(--card-accent);
  box-shadow: 0 4px 12px color-mix(in srgb, var(--card-accent) 24%, transparent);
  font-size: 1.1rem;
  font-weight: 700;
}

.featured {
  margin-top: 18px;
}

.feature-controls {
  position: absolute;
  z-index: 4;
  top: 16px;
  right: 16px;
  display: flex;
  gap: 7px;
}

.feature-controls button {
  display: grid;
  width: 39px;
  height: 39px;
  padding: 0;
  place-items: center;
  border: 1px solid rgba(18, 63, 67, 0.12);
  border-radius: 50%;
  color: var(--teal-800);
  background: rgba(255, 255, 255, 0.92);
  box-shadow: 0 5px 16px rgba(18, 63, 67, 0.1);
  cursor: pointer;
}

.feature-controls button:hover {
  color: #fff;
  background: var(--teal-800);
}

.feature-window {
  position: relative;
  overflow: hidden;
  border: 0;
  border-radius: 11px;
  background: #fff;
  box-shadow: 0 16px 46px rgba(19, 66, 67, 0.08);
}

.feature-viewport {
  overflow-x: auto;
  overscroll-behavior-inline: contain;
  scroll-snap-type: inline mandatory;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.feature-viewport::-webkit-scrollbar {
  display: none;
}

.feature-track {
  display: flex;
  width: 100%;
}

.feature-slide {
  --feature-surface: 235, 246, 243;
  position: relative;
  isolation: isolate;
  overflow: hidden;
  min-width: 100%;
  flex: 0 0 100%;
  min-height: clamp(450px, 30vw, 500px);
  margin: 0;
  background: rgb(var(--feature-surface));
  scroll-snap-align: start;
}

.feature-slide:nth-child(2) {
  --feature-surface: 248, 242, 226;
}

.feature-slide:nth-child(3) {
  --feature-surface: 232, 244, 241;
}

.feature-slide::after {
  position: absolute;
  z-index: 1;
  inset: 0;
  content: "";
  pointer-events: none;
  background: linear-gradient(
    90deg,
    rgb(var(--feature-surface)) 0%,
    rgb(var(--feature-surface)) 30%,
    rgba(var(--feature-surface), 0.96) 34%,
    rgba(var(--feature-surface), 0.52) 40%,
    rgba(var(--feature-surface), 0.1) 47%,
    transparent 53%
  );
}

.feature-copy {
  position: relative;
  z-index: 2;
  display: flex;
  width: min(49%, 570px);
  min-height: clamp(450px, 30vw, 500px);
  padding: clamp(28px, 3.6vw, 46px);
  flex-direction: column;
  align-items: flex-start;
  justify-content: center;
  background: transparent;
}

.feature-copy h3 {
  margin: 0;
  color: var(--teal-950);
  font-family: var(--editorial-font);
  font-size: clamp(1.65rem, 2.35vw, 2.25rem);
  font-weight: 600;
  letter-spacing: -0.025em;
  line-height: 1.02;
}

.feature-copy h4 {
  margin: 17px 0 0;
  color: var(--teal-800);
  font-family: var(--chinese-font);
  font-size: clamp(1.65rem, 2.35vw, 2.25rem);
  font-weight: 600;
  letter-spacing: -0.035em;
  line-height: 1.08;
}

.feature-copy > span {
  max-width: 36ch;
  margin-top: 20px;
  color: #4f696a;
  font-size: 0.96rem;
  line-height: 1.45;
}

.feature-copy a {
  display: inline-flex;
  margin-top: 22px;
  padding: 10px 17px;
  align-items: center;
  gap: 12px;
  border-radius: 999px;
  color: #fff;
  background: var(--teal-700);
  font-size: 0.84rem;
  font-weight: 700;
  text-decoration: none;
}

.feature-copy a:hover {
  background: var(--teal-800);
}

.feature-copy b {
  font-size: 1rem;
}

.feature-slide img {
  position: absolute;
  z-index: 0;
  top: 0;
  right: 0;
  display: block;
  width: 72%;
  height: 100%;
  object-fit: cover;
  object-position: center 42%;
}

.feature-dots {
  display: flex;
  margin-top: 11px;
  justify-content: center;
  gap: 8px;
}

.feature-dots button {
  width: 8px;
  height: 8px;
  padding: 0;
  border: 0;
  border-radius: 999px;
  background: #c3d9d4;
  cursor: pointer;
  transition: width 180ms ease, background 180ms ease;
}

.feature-dots button[aria-current="true"] {
  width: 26px;
  background: var(--teal-700);
}

.site-footer {
  display: flex;
  padding: 20px 4px 28px;
  align-items: center;
  justify-content: center;
  gap: 12px;
  border-top: 1px solid rgba(25, 91, 92, 0.13);
  color: #746d68;
}

.site-footer img {
  flex: 0 0 auto;
  width: 52px;
  height: 52px;
  object-fit: contain;
}

.footer-copy {
  display: grid;
  min-width: 0;
  gap: 1px;
  justify-items: start;
  text-align: left;
}

.footer-copy strong {
  color: #5d5753;
  font-size: 0.9rem;
  font-weight: 700;
  line-height: 1.3;
}

.footer-copy span {
  font-size: 0.82rem;
  line-height: 1.4;
}

@media (min-width: 651px) and (max-width: 1180px) {
  .pathways {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    align-items: stretch;
  }

  .pathway-card,
  .pathway-culture {
    grid-column: auto;
    grid-template-columns: minmax(0, 1fr) 34px;
    grid-template-rows: auto auto;
    min-height: 0;
    padding: 0 12px 15px;
    align-content: start;
    align-items: start;
    gap: 10px 8px;
  }

  .pathway-visual {
    grid-column: 1 / -1;
    grid-row: 1;
    width: calc(100% + 24px);
    margin-left: -12px;
    align-self: start;
  }

  .pathway-visual::after {
    top: auto;
    right: 0;
    bottom: -1px;
    left: 0;
    width: auto;
    height: 34px;
    background: linear-gradient(180deg, transparent, var(--card-bg));
  }

  .pathway-copy {
    grid-column: 1;
    grid-row: 2;
    align-self: start;
  }

  .pathway-copy strong {
    font-size: clamp(1.25rem, 2.2vw, 1.45rem);
  }

  .pathway-copy small {
    font-size: clamp(0.9rem, 1.7vw, 1rem);
  }

  .pathway-copy > span {
    font-size: clamp(0.8rem, 1.45vw, 0.9rem);
  }

  .pathway-arrow {
    grid-column: 2;
    grid-row: 2;
    align-self: end;
  }
}

@media (max-width: 900px) {
  .site-header {
    grid-template-columns: 1fr auto auto;
  }

  .menu-toggle {
    display: grid;
    grid-column: 3;
  }

  .about-menu {
    grid-column: 2;
    grid-row: 1;
    margin-right: 8px;
  }

  .primary-nav {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    display: none;
    width: min(280px, calc(100vw - 32px));
    padding: 8px;
    align-items: stretch;
    flex-direction: column;
    border: 1px solid var(--line);
    border-radius: 18px;
    background: #fff;
    box-shadow: var(--shadow);
  }

  .primary-nav.is-open {
    display: flex;
  }

  .primary-nav a {
    padding: 14px 15px;
  }

  .feature-copy {
    width: 58%;
  }

}

@media (max-width: 650px) {
  .page-shell,
  .site-footer {
    width: auto;
    margin-inline: 10px;
  }

  .site-header {
    width: 100%;
    min-height: 68px;
    margin: 0;
    padding: 8px 10px;
    border-radius: 0;
  }

  .brand img {
    width: 46px;
    height: 46px;
  }

  .brand .brand-nihao,
  .brand .brand-world {
    font-size: 1.48rem;
  }

  .menu-toggle {
    grid-column: 3;
  }

  .hero {
    min-height: 96px;
    border-radius: 0;
  }

  .hero-copy {
    padding: 12px 12px 20px;
  }

  .hero h1 a {
    display: grid;
    row-gap: clamp(8px, 2.3vw, 12px);
  }

  .hero h1 {
    font-size: clamp(1.85rem, 8.8vw, 2.35rem);
    line-height: 1.12;
  }

  .pathways {
    grid-template-columns: 1fr;
    margin: 0;
  }

  .pathway-card {
    grid-template-columns: minmax(110px, 38%) minmax(0, 1fr) 31px;
    min-height: 132px;
    padding-right: 9px;
    gap: 8px;
  }

  .pathway-copy strong {
    font-size: 1.3rem;
  }

  .pathway-copy small {
    font-size: 0.9rem;
  }

  .pathway-copy > span {
    display: none;
  }

  .feature-slide {
    display: block;
    min-height: 520px;
  }

  .feature-slide img {
    width: 100%;
    height: 60%;
    object-position: center 35%;
  }

  .feature-slide::after {
    background: linear-gradient(
      180deg,
      transparent 0%,
      rgba(var(--feature-surface), 0.08) 26%,
      rgba(var(--feature-surface), 0.72) 43%,
      rgb(var(--feature-surface)) 57%,
      rgb(var(--feature-surface)) 100%
    );
  }

  .feature-copy {
    width: 100%;
    min-height: 520px;
    padding: 268px 24px 26px;
    justify-content: flex-start;
  }

  .feature-copy h3,
  .feature-copy h4 {
    max-width: 20ch;
    font-size: clamp(1.55rem, 7vw, 2rem);
  }

  .site-footer {
    padding-top: 16px;
    padding-inline: 6px;
    gap: 8px;
  }

  .site-footer img {
    width: 44px;
    height: 44px;
  }

  .footer-copy strong {
    font-size: 0.84rem;
  }

  .footer-copy span {
    font-size: 0.76rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}