:root {
  --paper: #f4f1e8;
  --paper-2: #ebe6da;
  --surface: #fffaf0;
  --ink: #101719;
  --ink-2: #18241f;
  --muted: rgba(16, 23, 25, 0.66);
  --line: rgba(16, 23, 25, 0.16);
  --pine: #24483a;
  --pine-2: #355f4d;
  --deep: #08100d;
  --stone: #8f887b;
  --clay: #a97c55;
  --red: #b60005;
  --rust: #b85243;
  --white: #fffdf7;
  --shadow: 0 24px 80px rgba(8, 16, 13, 0.18);
  color-scheme: light;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans TC", sans-serif;
  line-height: 1.5;
  letter-spacing: 0;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  overflow-x: hidden;
}

section[id] {
  scroll-margin-top: 96px;
}

body {
  width: 100%;
  max-width: 100%;
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  overflow-x: hidden;
}

body::before {
  position: fixed;
  inset: 0;
  z-index: -1;
  background-image: url("assets/brand/washi-texture.png");
  background-size: 620px auto;
  opacity: 0.12;
  content: "";
  pointer-events: none;
}

img,
svg {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
}

button,
input,
select,
textarea {
  font: inherit;
}

.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 76px;
  padding: 0 34px;
  color: var(--white);
  transition: background 180ms ease, color 180ms ease, box-shadow 180ms ease;
}

.site-header.is-scrolled {
  background: rgba(244, 241, 232, 0.95);
  color: var(--ink);
  box-shadow: 0 1px 0 var(--line);
  backdrop-filter: blur(18px);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
}

.brand img {
  width: 46px;
  height: 46px;
  object-fit: contain;
  filter: drop-shadow(0 8px 18px rgba(0, 0, 0, 0.28));
  flex: 0 0 auto;
}

.site-header.is-scrolled .brand img {
  filter: none;
}

.brand strong,
.brand small {
  display: block;
  line-height: 1.08;
}

.brand strong {
  font-size: 0.98rem;
  font-weight: 900;
}

.brand small {
  margin-top: 4px;
  color: currentColor;
  font-size: 0.74rem;
  opacity: 0.74;
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 18px;
  min-width: 0;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 24px;
  font-size: 0.86rem;
  font-weight: 850;
}

.site-header:not(.is-scrolled) .site-nav {
  padding: 8px 12px;
  border: 1px solid rgba(255, 253, 247, 0.16);
  border-radius: 6px;
  background: rgba(8, 16, 13, 0.64);
  backdrop-filter: blur(12px);
}

.site-nav a {
  opacity: 0.82;
}

.site-nav a:hover {
  opacity: 1;
}

.language-switch {
  display: inline-flex;
  flex: 0 0 auto;
  gap: 3px;
  padding: 4px;
  background: rgba(255, 253, 247, 0.1);
  border: 1px solid rgba(255, 253, 247, 0.24);
  border-radius: 6px;
  backdrop-filter: blur(12px);
}

.site-header:not(.is-scrolled) .language-switch {
  background: rgba(8, 16, 13, 0.64);
  border-color: rgba(255, 253, 247, 0.22);
}

.language-switch button {
  min-height: 32px;
  padding: 0 10px;
  border: 0;
  border-radius: 4px;
  background: transparent;
  color: inherit;
  cursor: pointer;
  font-size: 0.74rem;
  font-weight: 900;
}

.language-switch button[aria-pressed="true"] {
  background: var(--white);
  color: var(--ink);
}

.site-header.is-scrolled .language-switch {
  background: rgba(16, 23, 25, 0.06);
  border-color: rgba(16, 23, 25, 0.14);
}

.site-header.is-scrolled .language-switch button[aria-pressed="true"] {
  background: var(--ink);
  color: var(--white);
}

.hero {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(380px, 0.72fr);
  gap: 56px;
  min-width: 0;
  min-height: 94svh;
  padding: 150px max(32px, calc((100vw - 1180px) / 2)) 64px;
  overflow: hidden;
  background:
    linear-gradient(90deg, rgba(8, 16, 13, 0.98), rgba(24, 36, 31, 0.94)),
    var(--deep);
  color: var(--white);
}

.hero-grid {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(255, 253, 247, 0.07) 1px, transparent 1px),
    linear-gradient(180deg, rgba(255, 253, 247, 0.06) 1px, transparent 1px);
  background-size: 92px 92px;
  mask-image: linear-gradient(90deg, #000 0%, rgba(0, 0, 0, 0.82) 52%, transparent 58%);
}

.hero::before,
.hero::after {
  position: absolute;
  top: 0;
  right: 0;
  width: 44%;
  height: 100%;
  background-color: #ece8dc;
  box-shadow:
    inset 36px 0 72px rgba(8, 16, 13, 0.24),
    inset -18px 0 52px rgba(92, 76, 52, 0.16);
  content: "";
  pointer-events: none;
}

.hero::before {
  background-image:
    linear-gradient(90deg, rgba(8, 16, 13, 0.32), rgba(255, 255, 255, 0) 17%),
    linear-gradient(0deg, rgba(219, 207, 182, 0.18), rgba(255, 249, 238, 0.08)),
    radial-gradient(circle at 44% 34%, rgba(255, 250, 238, 0.2), rgba(255, 250, 238, 0) 42%);
  background-size: auto, auto, auto;
  background-position: center;
}

.hero::after {
  background-image:
    linear-gradient(90deg, rgba(8, 16, 13, 0.32), rgba(255, 255, 255, 0) 17%),
    linear-gradient(0deg, rgba(211, 190, 154, 0.34), rgba(255, 249, 238, 0.12)),
    radial-gradient(circle at 44% 34%, rgba(255, 250, 238, 0.28), rgba(255, 250, 238, 0) 42%),
    url("assets/brand/paper-real.jpg");
  background-size: auto, auto, auto, cover;
  background-position: center;
  opacity: 1;
}

.hero-content,
.hero-mark {
  position: relative;
  z-index: 1;
  align-self: center;
  min-width: 0;
}

.hero-content {
  width: 100%;
}

.eyebrow {
  margin: 0 0 16px;
  color: var(--rust);
  font-size: 0.76rem;
  font-weight: 950;
  text-transform: uppercase;
}

.section-dark .eyebrow,
.section-ink .eyebrow,
.hero .eyebrow {
  color: #f0b18d;
}

h1,
h2,
h3,
p,
li,
dd,
dt,
.button,
.brand strong,
.brand small {
  overflow-wrap: anywhere;
}

h1,
h2,
h3,
p,
figure {
  margin-top: 0;
}

h1 {
  max-width: 760px;
  margin-bottom: 26px;
  font-family: Georgia, "Times New Roman", "Noto Serif TC", serif;
  font-size: 74px;
  font-weight: 500;
  line-height: 0.98;
  white-space: pre-line;
  text-wrap: balance;
  overflow-wrap: normal;
  word-break: keep-all;
}

h2 {
  margin-bottom: 18px;
  font-family: Georgia, "Times New Roman", "Noto Serif TC", serif;
  font-size: 42px;
  font-weight: 500;
  line-height: 1.08;
}

h3 {
  margin-bottom: 10px;
  font-size: 1.12rem;
  line-height: 1.32;
}

.hero-lead {
  max-width: 710px;
  margin-bottom: 14px;
  color: rgba(255, 253, 247, 0.88);
  font-size: 1.2rem;
  line-height: 1.72;
}

.hero-support {
  max-width: 660px;
  margin-bottom: 34px;
  color: rgba(255, 253, 247, 0.66);
  font-size: 1rem;
  line-height: 1.72;
}

.hero h1,
.hero p {
  max-width: 100%;
}

body[data-lang="en"] .hero h1 {
  font-size: 58px;
  line-height: 1.04;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 20px;
  border: 1px solid transparent;
  border-radius: 4px;
  background: transparent;
  color: inherit;
  cursor: pointer;
  font-weight: 900;
  transition: transform 160ms ease, background 160ms ease, color 160ms ease, border-color 160ms ease;
}

.button:hover {
  transform: translateY(-1px);
}

.button.primary {
  background: var(--red);
  color: var(--white);
}

.button.secondary {
  border-color: rgba(255, 253, 247, 0.36);
  color: var(--white);
}

.section-light .button.secondary {
  border-color: var(--line);
  color: var(--ink);
}

.hero-mark {
  justify-self: end;
  width: 420px;
  max-width: 100%;
  margin: 0;
  border-left: 0;
  padding-left: 30px;
}

.hero-mark img {
  width: 100%;
  aspect-ratio: 105 / 129.4;
  object-fit: contain;
  filter: contrast(1.16);
}

.hero-mark figcaption {
  display: grid;
  gap: 8px;
  margin-top: 16px;
}

.hero-mark span {
  color: var(--rust);
  font-size: 0.74rem;
  font-weight: 950;
  text-transform: uppercase;
}

.hero-mark strong {
  color: var(--ink);
  font-size: 1.2rem;
}

.section-light,
.section-dark,
.section-ink {
  padding: 104px 0;
}

.section-light {
  background: var(--paper);
}

.lineage.section-light {
  padding-bottom: 72px;
}

.lineage + .architecture.section-light {
  padding-top: 72px;
  border-top: 1px solid var(--line);
}

.section-dark {
  background: var(--ink-2);
  color: var(--white);
}

.section-ink {
  background: var(--deep);
  color: var(--white);
}

.section-inner {
  width: min(1180px, calc(100% - 48px));
  margin: 0 auto;
}

.section-heading {
  max-width: 820px;
  margin-bottom: 42px;
}

.section-heading.split {
  display: grid;
  max-width: none;
  grid-template-columns: minmax(0, 0.85fr) minmax(300px, 0.6fr);
  gap: 72px;
  align-items: end;
}

.section-heading p,
.definition-grid p,
.feature-stack p,
.path-grid p,
.ask-inner p,
.contact-grid p,
.form-note {
  color: var(--muted);
}

.section-dark .section-heading p,
.section-dark p,
.section-ink .section-heading p,
.section-ink p {
  color: rgba(255, 253, 247, 0.68);
}

.definition-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.definition-grid article {
  min-height: 300px;
  padding: 26px;
  background:
    linear-gradient(180deg, rgba(255, 250, 240, 0.96), rgba(255, 250, 240, 0.88)),
    var(--surface);
}

.definition-grid span,
.path-grid span {
  display: block;
  margin-bottom: 42px;
  color: var(--red);
  font-weight: 950;
}

.definition-grid h3 {
  font-size: 1.35rem;
}

.definition-grid p,
.feature-stack p,
.path-grid p {
  margin-bottom: 0;
  line-height: 1.72;
}

.contrast-grid,
.architecture-grid,
.contact-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.88fr) minmax(0, 1.12fr);
  gap: 72px;
  align-items: center;
}

.contrast-grid > div:first-child p,
.contact-grid > div:first-child p {
  max-width: 640px;
  line-height: 1.75;
}

.contrast-list {
  display: grid;
  gap: 12px;
}

.contrast-list article {
  display: grid;
  grid-template-columns: 92px minmax(0, 1fr);
  gap: 10px 18px;
  padding: 22px;
  background: rgba(255, 253, 247, 0.07);
  border: 1px solid rgba(255, 253, 247, 0.14);
  border-radius: 8px;
}

.contrast-list article.is {
  background: rgba(182, 0, 5, 0.18);
  border-color: rgba(240, 177, 141, 0.26);
}

.contrast-list span {
  grid-row: span 2;
  color: #f0b18d;
  font-size: 0.76rem;
  font-weight: 950;
  text-transform: uppercase;
}

.contrast-list strong {
  font-size: 1.12rem;
}

.contrast-list p {
  margin: 0;
}

.lineage-inner {
  display: grid;
  gap: 36px;
}

.lineage-heading {
  display: grid;
  grid-template-columns: minmax(0, 0.82fr) minmax(320px, 0.68fr);
  gap: 72px;
  align-items: end;
}

.lineage-heading h2 {
  max-width: 720px;
}

body[data-lang="zh"] .lineage-heading h2 {
  word-break: keep-all;
}

.lineage-heading > p {
  max-width: 620px;
  margin-bottom: 0;
  color: var(--muted);
  line-height: 1.78;
}

.lineage-feature {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(420px, 0.82fr);
  gap: 28px;
  align-items: start;
}

.lineage-visual {
  display: grid;
  gap: 18px;
  min-width: 0;
}

.lineage-portrait {
  margin: 0;
  overflow: hidden;
  aspect-ratio: 4 / 3;
  border-radius: 8px;
  background: var(--ink);
  box-shadow: var(--shadow);
}

.lineage-portrait img {
  width: 100%;
  height: 100%;
  min-height: 0;
  object-fit: cover;
  object-position: center;
  filter: saturate(0.98) contrast(1.02);
}

.lineage-copy {
  display: grid;
  align-content: center;
  padding: 28px 32px;
  background:
    linear-gradient(180deg, rgba(255, 250, 240, 0.72), rgba(255, 250, 240, 0.42)),
    rgba(255, 250, 240, 0.52);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.lineage-copy p {
  margin: 0;
  color: rgba(16, 23, 25, 0.78);
  font-size: 0.98rem;
  line-height: 1.74;
}

.lineage-copy p + p {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid rgba(16, 23, 25, 0.1);
}

.lineage-facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  background: var(--line);
  border: 1px solid var(--line);
}

.lineage-facts div {
  display: grid;
  gap: 12px;
  min-height: 124px;
  padding: 22px;
  background:
    linear-gradient(180deg, rgba(255, 250, 240, 0.96), rgba(255, 250, 240, 0.86)),
    var(--surface);
}

.lineage-facts dt {
  color: var(--red);
  font-size: 0.76rem;
  font-weight: 950;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.lineage-facts dd {
  margin: 0;
  color: var(--ink);
  font-size: 1rem;
  font-weight: 850;
  line-height: 1.45;
}

body[data-lang="en"] .lineage-facts {
  grid-template-columns: 1fr;
}

body[data-lang="en"] .lineage-facts div {
  min-height: 0;
}

.architecture figure {
  margin: 0;
}

.architecture figure img {
  width: 100%;
  aspect-ratio: 1 / 0.78;
  object-fit: cover;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.feature-stack {
  display: grid;
  gap: 16px;
}

.feature-stack article {
  padding: 22px 0;
  border-top: 1px solid var(--line);
}

.feature-stack h3 {
  color: var(--pine);
}

.path-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.path-grid article {
  display: grid;
  grid-template-rows: auto auto auto 1fr;
  min-height: 420px;
  overflow: hidden;
  background: rgba(255, 253, 247, 0.08);
  border: 1px solid rgba(255, 253, 247, 0.13);
  border-radius: 8px;
}

.path-grid img {
  width: 100%;
  aspect-ratio: 1 / 0.72;
  object-fit: cover;
  opacity: 0.84;
}

.path-grid span,
.path-grid h3,
.path-grid p {
  margin-right: 20px;
  margin-left: 20px;
}

.path-grid span {
  margin-top: 22px;
  margin-bottom: 22px;
  color: #f0b18d;
}

.path-grid h3 {
  color: var(--white);
  font-size: 1.2rem;
}

.ask-inner {
  display: grid;
  gap: 36px;
}

.video-teaser {
  display: grid;
  grid-template-columns: minmax(0, 0.8fr) minmax(320px, 0.62fr);
  gap: 72px;
  align-items: end;
  padding: 34px;
  background:
    linear-gradient(135deg, rgba(255, 250, 240, 0.88), rgba(255, 250, 240, 0.48)),
    var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.video-teaser h2 {
  margin-bottom: 0;
}

.video-teaser-copy {
  display: grid;
  gap: 18px;
  justify-items: start;
}

.video-teaser-copy p {
  margin: 0;
  line-height: 1.72;
}

.videos-page {
  background: var(--paper);
}

.video-hero {
  padding-top: 158px;
}

.video-hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 0.86fr) minmax(320px, 0.48fr);
  gap: 72px;
  align-items: end;
}

.video-hero h1 {
  font-size: clamp(42px, 5vw, 72px);
}

.video-hero-card {
  display: grid;
  gap: 18px;
  min-height: 240px;
  padding: 28px;
  align-content: end;
  background:
    linear-gradient(180deg, rgba(255, 253, 247, 0.12), rgba(255, 253, 247, 0.04)),
    rgba(255, 253, 247, 0.08);
  border: 1px solid rgba(255, 253, 247, 0.16);
  border-radius: 8px;
}

.video-hero-card span {
  color: #f0b18d;
  font-size: 0.76rem;
  font-weight: 950;
}

.video-hero-card strong {
  color: rgba(255, 253, 247, 0.86);
  font-size: 0.95rem;
  line-height: 1.5;
  overflow-wrap: anywhere;
}

.video-watch-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 0.42fr);
  gap: 34px;
  align-items: start;
}

.video-frame {
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background: var(--ink);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.video-frame iframe {
  width: 100%;
  height: 100%;
  border: 0;
}

.video-guide {
  display: grid;
  gap: 16px;
  padding: 28px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.video-guide h2 {
  margin-bottom: 0;
  font-size: 30px;
}

.video-guide p {
  margin: 0;
  color: var(--muted);
  line-height: 1.72;
}

.video-guide ul {
  display: grid;
  gap: 10px;
  margin: 8px 0 0;
  padding: 0;
  list-style: none;
}

.video-guide li {
  padding: 12px 0;
  border-top: 1px solid var(--line);
  color: var(--ink);
  font-weight: 850;
}

.coze-chat-shell {
  position: relative;
  overflow: hidden;
  min-height: 700px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.coze-chat-container {
  position: relative;
  display: flex;
  flex-direction: column;
  width: 100%;
  height: 700px;
  min-height: 700px;
  background: var(--surface);
}

.coze-chat-container > * {
  min-width: 0;
}

.coze-panel {
  display: grid;
  grid-template-rows: auto minmax(0, 1fr) auto;
  height: 100%;
  min-height: 0;
}

.coze-panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 22px;
  border-bottom: 1px solid var(--line);
}

.coze-panel-header strong {
  color: var(--ink);
  font-size: 1rem;
  font-weight: 950;
}

.coze-panel-header span {
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 800;
}

.coze-messages {
  display: grid;
  align-content: start;
  gap: 14px;
  overflow-y: auto;
  padding: 22px;
}

.coze-message {
  max-width: min(720px, 86%);
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 250, 240, 0.72);
  color: rgba(16, 23, 25, 0.86);
  line-height: 1.72;
  white-space: pre-wrap;
}

.coze-message.user {
  justify-self: end;
  background: var(--ink);
  color: var(--white);
}

.coze-message.error {
  border-color: rgba(182, 0, 5, 0.22);
  background: rgba(182, 0, 5, 0.08);
  color: #8f1619;
}

.coze-form {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 12px;
  padding: 18px 22px;
  border-top: 1px solid var(--line);
}

.coze-form textarea {
  min-height: 52px;
  max-height: 132px;
  padding: 14px;
  border: 1px solid rgba(16, 23, 25, 0.16);
  border-radius: 6px;
  background: #f7f2e7;
  color: var(--ink);
  resize: vertical;
  outline: none;
}

.coze-form textarea:focus {
  border-color: var(--pine-2);
  box-shadow: 0 0 0 3px rgba(53, 95, 77, 0.16);
}

.coze-form button {
  align-self: end;
  min-width: 112px;
}

.coze-chat-fallback {
  align-self: center;
  justify-self: center;
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
  font-weight: 800;
}

.contact-form {
  display: grid;
  gap: 16px;
  padding: 28px;
  background: var(--surface);
  border-radius: 8px;
  color: var(--ink);
}

.contact-form label {
  display: grid;
  gap: 8px;
  font-size: 0.82rem;
  font-weight: 950;
}

.contact-form input,
.contact-form select,
.contact-form textarea {
  width: 100%;
  border: 1px solid rgba(16, 23, 25, 0.18);
  border-radius: 4px;
  background: #f7f2e7;
  color: var(--ink);
  outline: none;
}

.contact-form input,
.contact-form select {
  height: 46px;
  padding: 0 12px;
}

.contact-form textarea {
  min-height: 132px;
  padding: 12px;
  resize: vertical;
}

.contact-form input:focus,
.contact-form select:focus,
.contact-form textarea:focus {
  border-color: var(--pine-2);
  box-shadow: 0 0 0 3px rgba(53, 95, 77, 0.16);
}

.contact-form .button {
  width: 100%;
}

.form-note {
  margin: 0;
  font-size: 0.86rem;
}

.form-note a {
  color: var(--pine);
  font-weight: 900;
}

.contact-card {
  display: grid;
  gap: 18px;
  padding: 34px;
  background: var(--surface);
  border: 1px solid rgba(16, 23, 25, 0.12);
  border-radius: 8px;
  color: var(--ink);
}

.contact-card-label {
  margin: 0;
  color: var(--red) !important;
  font-size: 0.82rem;
  font-weight: 950;
}

.contact-mail {
  color: var(--ink);
  font-size: clamp(1.35rem, 2vw, 2rem);
  font-weight: 950;
  line-height: 1.16;
  overflow-wrap: anywhere;
  text-decoration: none;
}

.contact-mail:hover {
  color: var(--red);
}

.contact-card-note {
  margin: 0;
  color: var(--muted) !important;
  line-height: 1.7;
}

.contact-button {
  width: fit-content;
}

.site-footer {
  padding: 28px 0;
  background: #050907;
  color: rgba(255, 253, 247, 0.72);
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.footer-inner p {
  margin: 0;
  color: var(--white);
  font-weight: 900;
}

.footer-inner span {
  margin-left: 8px;
  color: rgba(255, 253, 247, 0.58);
}

.footer-inner nav {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  font-size: 0.86rem;
  font-weight: 850;
}

@media (max-width: 1080px) {
  .site-header {
    align-items: flex-start;
    flex-direction: column;
    gap: 12px;
    padding: 16px 20px;
  }

  .header-controls {
    width: 100%;
    gap: 8px;
  }

  .site-nav {
    width: auto;
    min-width: 0;
    flex: 1 1 auto;
    gap: 4px;
    padding: 8px;
    overflow-x: auto;
    background: rgba(8, 16, 13, 0.58);
    border: 1px solid rgba(255, 253, 247, 0.18);
    border-radius: 6px;
    color: var(--white);
    backdrop-filter: blur(12px);
    font-size: 0.74rem;
  }

  .site-header:not(.is-scrolled) .site-nav {
    padding: 8px;
  }

  .site-header.is-scrolled .site-nav {
    background: rgba(16, 23, 25, 0.08);
    color: var(--ink);
  }

  .site-nav a {
    flex: 0 0 auto;
    padding: 0 10px;
  }

  .language-switch {
    background: rgba(8, 16, 13, 0.58);
  }

  .hero::before,
  .hero::after {
    display: none;
  }

  .hero {
    grid-template-columns: 1fr;
    gap: 40px;
    padding-top: 170px;
  }

  .hero h1 {
    font-size: clamp(48px, 8vw, 64px);
  }

  .hero-mark {
    justify-self: start;
    width: 420px;
    max-width: 100%;
    border-left: 0;
    padding: 24px;
    border-radius: 8px;
    background-color: #ece8dc;
    background-image:
      linear-gradient(0deg, rgba(219, 207, 182, 0.18), rgba(255, 249, 238, 0.08)),
      radial-gradient(circle at 44% 34%, rgba(255, 250, 238, 0.2), rgba(255, 250, 238, 0) 42%);
    background-size: auto, auto;
    background-position: center;
    box-shadow: 0 20px 50px rgba(2, 7, 5, 0.24);
  }

  body.paper-ready .hero-mark {
    background-image:
      linear-gradient(0deg, rgba(211, 190, 154, 0.34), rgba(255, 249, 238, 0.12)),
      radial-gradient(circle at 44% 34%, rgba(255, 250, 238, 0.28), rgba(255, 250, 238, 0) 42%),
      url("assets/brand/paper-real.jpg");
    background-size: auto, auto, cover;
  }

  .hero-mark img {
    max-width: min(340px, 100%);
    margin: 0 auto;
  }

  .definition-grid,
  .path-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .contrast-grid,
  .lineage-heading,
  .lineage-feature,
  .architecture-grid,
  .contact-grid,
  .video-teaser,
  .video-hero-inner,
  .video-watch-grid,
  .section-heading.split {
    grid-template-columns: 1fr;
    gap: 34px;
  }

  .lineage-portrait img {
    min-height: 0;
  }
}

@media (max-width: 680px) {
  .site-header {
    min-height: 0;
  }

  .brand strong {
    max-width: 250px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .brand img {
    width: 42px;
    height: 42px;
  }

  .header-controls {
    align-items: flex-start;
    flex-direction: column;
    width: 100%;
    max-width: 100%;
  }

  .site-nav {
    width: 100%;
    max-width: 100%;
    gap: 2px;
    padding: 6px;
    font-size: 0.72rem;
  }

  .site-header:not(.is-scrolled) .site-nav {
    padding: 6px;
  }

  .site-nav a {
    padding: 0 6px;
  }

  .hero {
    grid-template-columns: minmax(0, 1fr);
    min-height: 0;
    padding: 164px 16px 48px;
    width: 100%;
    max-width: 100%;
    justify-items: stretch;
  }

  .hero > * {
    min-width: 0;
  }

  .hero-content {
    width: 100%;
    max-width: 100%;
  }

  .hero-mark {
    width: 100%;
    max-width: 100%;
    padding: 18px;
  }

  .hero h1 {
    max-width: 100%;
    font-size: 34px;
    line-height: 1.04;
    width: 100%;
    white-space: pre-line;
    overflow-wrap: normal;
    word-break: keep-all;
    line-break: strict;
  }

  body[data-lang="en"] .hero h1 {
    max-width: 100%;
    font-size: 31px;
    line-height: 1.06;
  }

  .video-hero h1 {
    font-size: 34px;
  }

  h2 {
    font-size: 30px;
    line-height: 1.12;
  }

  .hero-lead,
  .hero-support {
    width: 100%;
    max-width: calc(100vw - 32px);
    overflow-wrap: anywhere;
    word-break: break-word;
    line-break: strict;
  }

  body[data-lang="zh"] .hero-lead,
  body[data-lang="zh"] .hero-support {
    word-break: break-all;
    line-break: loose;
  }

  .hero-lead {
    font-size: 1.05rem;
  }

  .hero-actions {
    display: grid;
    width: 100%;
    max-width: 100%;
  }

  .hero-actions .button {
    width: 100%;
  }

  .section-light,
  .section-dark,
  .section-ink {
    padding: 74px 0;
  }

  .lineage.section-light {
    padding-bottom: 54px;
  }

  .lineage + .architecture.section-light {
    padding-top: 54px;
  }

  .section-inner {
    width: calc(100% - 32px);
  }

  .definition-grid,
  .path-grid {
    grid-template-columns: 1fr;
  }

  .definition-grid article {
    min-height: 240px;
    padding: 22px;
  }

  .lineage-facts {
    grid-template-columns: 1fr;
  }

  .lineage-facts div {
    min-height: 0;
    gap: 6px;
  }

  .lineage-copy {
    padding: 22px;
  }

  .lineage-portrait img {
    min-height: 0;
  }

  .hero-mark img {
    max-width: min(300px, calc(100vw - 68px));
  }

  .hero-mark figcaption {
    width: 100%;
  }

  .coze-chat-shell,
  .coze-chat-container {
    min-height: 640px;
  }

  .coze-chat-container {
    height: 640px;
  }

  .coze-form {
    grid-template-columns: 1fr;
  }

  .coze-form button {
    width: 100%;
  }

  .coze-message {
    max-width: 100%;
  }

  .video-teaser,
  .video-guide {
    padding: 22px;
  }

  .video-hero {
    padding-top: 164px;
  }

  .video-hero-card {
    min-height: 160px;
    padding: 22px;
  }

  .contrast-list article {
    grid-template-columns: 1fr;
  }

  .contrast-list span {
    grid-row: auto;
  }

  .path-grid article {
    min-height: 360px;
  }

  .contact-card,
  .contact-form {
    padding: 22px;
  }

  .footer-inner {
    align-items: flex-start;
    flex-direction: column;
  }
}