:root {
  /* Chữ kem trên nền navy; header bar + footer bar dùng --header-bar-bg; vùng kem thẻ concept dùng --card-title-* */
  --ink: #f8f1e3;
  --header-bar-bg: var(--canvas-bg);
  --header-bg: var(--canvas-bg);
  --header-text: var(--ink);
  --card-title-bg: #f8f1e3;
  --card-title-text: #1a1a1a;
  --canvas-bg: #152238;
  --landing-hero-text: var(--ink);
  --bg: var(--canvas-bg);
  --surface: #1c2e48;
  --border: rgba(255, 255, 255, 0.12);
  --text: var(--ink);
  --muted: var(--ink);
  --accent: var(--ink);
  --accent-dim: var(--ink);
  --concept-name: var(--ink);
  /** Cùng nội dung grid/footer bar + căn banner landing với footer. */
  --footer-inner-max: min(1420px, 100%);
  --shadow: rgba(0, 0, 0, 0.35);
  --header-bar-offset: 11.25rem;
  --ease-page-entrance: cubic-bezier(0.22, 1, 0.36, 1);
  /* Sans hiện đại, chữ hoa (như INDOCHINE trên mockup) */
  --font-display: "Montserrat", ui-sans-serif, system-ui, sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  scrollbar-gutter: stable;
  /** Tránh iOS/Safari chỉnh cỡ chữ làm layout “phóng” khi xoay ngang. */
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

/* Landing: chỉ #landing-snap-viewport cuộn dọc — khóa overflow document để không hai thanh scroll. */

html:has(body.is-landing) {
  overflow-y: hidden;
  height: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  font-family: "Cormorant Garamond", "Georgia", serif;
  background: var(--canvas-bg);
  color: var(--text);
  line-height: 1.5;
}

body.is-landing {
  overflow-y: hidden;
  min-height: 100vh;
  min-height: 100dvh;
  max-height: 100dvh;
  height: 100dvh;
  background: var(--canvas-bg);
}

#view-landing:not([hidden]),
#view-overview:not([hidden]),
#view-concept:not([hidden]),
#view-about:not([hidden]) {
  flex: 1 0 auto;
}

/* Landing chiếm hết chiều cao body (đã khóa 100dvh) để chỉ còn một vùng cuộn snap */
body.is-landing #view-landing:not([hidden]) {
  flex: 1 1 auto;
  min-height: 0;
}

.site-footer {
  flex-shrink: 0;
  margin-top: auto;
  padding: 0;
  border-top: none;
  background: var(--canvas-bg);
  font-family: var(--font-display), system-ui, sans-serif;
  font-size: clamp(0.72rem, 1.65vw, 0.82rem);
  color: rgba(248, 241, 227, 0.82);
}

body.is-landing .landing-footer-host .site-footer {
  margin-top: 0;
}

.site-footer-main {
  padding: 1.75rem clamp(0.85rem, 4vw, 3rem) 2rem;
}

.site-footer-grid {
  width: 100%;
  max-width: var(--footer-inner-max);
  margin-inline: auto;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  column-gap: clamp(1.25rem, 3vw, 2rem);
  row-gap: 1.75rem;
  align-items: start;
  justify-items: stretch;
}

.site-footer-grid > .footer-col {
  min-width: 0;
  text-align: start;
  overflow-wrap: break-word;
}

@media (min-width: 1025px) {
  .site-footer-grid {
    display: flex;
    flex-direction: row;
    flex-wrap: nowrap;
    justify-content: space-between;
    align-items: flex-start;
    gap: 0;
  }

  .site-footer-grid > .footer-col {
    flex: 0 1 auto;
    width: auto;
    min-width: 0;
    max-width: none;
  }

  .site-footer-grid > .footer-col:first-child {
    max-width: min(32rem, 52%);
  }

  .site-footer-grid > .footer-col--map {
    flex: 0 0 auto;
  }
}

.footer-col--dmca {
  min-width: 0;
}

.footer-dmca-body {
  margin: 0;
  line-height: 1.5;
  color: rgba(248, 241, 227, 0.72);
  font-weight: 500;
  font-size: clamp(0.7rem, 1.5vw, 0.8rem);
}

.footer-col--map {
  min-width: 0;
}

.footer-col--map .footer-map-wrap {
  width: 100%;
  max-width: min(200px, 100%);
  max-height: min(130px, 24vw);
}

.footer-heading {
  margin: 0 0 1rem;
  font-size: clamp(0.68rem, 1.55vw, 0.78rem);
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(248, 241, 227, 0.92);
}

.footer-contact-list,
.footer-social-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.footer-contact-list li {
  display: flex;
  gap: 0.65rem;
  align-items: flex-start;
  margin-bottom: 0.85rem;
  line-height: 1.45;
  color: rgba(248, 241, 227, 0.88);
}

.footer-contact-list li:last-child {
  margin-bottom: 0;
}

.footer-contact-icon {
  flex-shrink: 0;
  margin-top: 0.1rem;
  color: rgba(248, 241, 227, 0.55);
}

.footer-contact-list a {
  color: inherit;
  text-decoration: underline;
  text-underline-offset: 2px;
}

.footer-social-list li {
  margin-bottom: 0.45rem;
}

.footer-social-list a {
  color: rgba(248, 241, 227, 0.88);
  text-decoration: underline;
  text-underline-offset: 2px;
}

.footer-map-wrap {
  border-radius: 6px;
  overflow: hidden;
  border: 1px solid rgba(248, 241, 227, 0.2);
  aspect-ratio: 4 / 3;
}

.footer-map-wrap iframe {
  display: block;
  width: 100%;
  height: 100%;
  min-height: 110px;
  border: 0;
}

@media (max-width: 1024px) {
  .site-footer-grid > .footer-col--map {
    max-width: none;
  }

  .footer-col--map {
    grid-column: span 1;
  }

  .footer-col--dmca {
    grid-column: span 1;
  }
}

@media (max-width: 560px) {
  .site-footer-grid {
    grid-template-columns: 1fr;
  }

  .site-footer-grid > .footer-col {
    width: auto;
    max-width: none;
  }

  .footer-col--map .footer-map-wrap {
    max-width: 100%;
    max-height: min(180px, 55vw);
  }
}

.site-footer-bar {
  border-top: none;
  padding: 0 clamp(0.85rem, 4vw, 3rem) 1.1rem;
}

.site-footer-bar-inner {
  max-width: var(--footer-inner-max);
  width: 100%;
  margin-inline: auto;
  border-top: 0.9px solid rgba(248, 241, 227, 0.24);
  padding-top: 0.85rem;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 0.65rem 1rem;
}

.site-footer-bar-spacer {
  grid-column: 1;
  min-width: 0;
}

.site-footer-lang {
  grid-column: 2;
  justify-self: center;
}

.site-footer-copy {
  grid-column: 3;
  justify-self: end;
  margin: 0;
  text-align: right;
  font-size: clamp(0.66rem, 1.35vw, 0.76rem);
  font-weight: 500;
  letter-spacing: 0.02em;
  color: rgba(248, 241, 227, 0.72);
  max-width: min(100%, 26rem);
}

.site-footer-copy__brand {
  font-weight: 700;
  color: rgba(248, 241, 227, 0.92);
}

.site-footer-copy__suffix {
  font-weight: 500;
  color: rgba(248, 241, 227, 0.72);
}

@media (max-width: 640px) {
  .site-footer-bar-inner {
    grid-template-columns: 1fr;
    justify-items: center;
    text-align: center;
  }

  .site-footer-bar-spacer {
    display: none;
  }

  .site-footer-lang {
    grid-column: 1;
    justify-self: center;
  }

  .site-footer-copy {
    grid-column: 1;
    justify-self: center;
    text-align: center;
    max-width: 100%;
  }
}

.scroll-to-top {
  position: fixed;
  right: clamp(0.85rem, 3.5vw, 1.15rem);
  bottom: clamp(1rem, 4vw, 1.35rem);
  z-index: 80;
  width: clamp(4.25rem, 17vw, 5.65rem);
  height: clamp(4.25rem, 17vw, 5.65rem);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  border-radius: 50%;
  border: none;
  background: transparent;
  color: rgba(248, 241, 227, 0.92);
  cursor: pointer;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.28s ease, color 0.2s ease, filter 0.2s ease;
}

.scroll-to-top.is-visible {
  opacity: 1;
  pointer-events: auto;
}

.scroll-to-top:hover {
  color: #fff;
  filter: drop-shadow(0 0 14px rgba(248, 241, 227, 0.18));
}

.scroll-to-top:focus-visible {
  outline: 2px solid rgba(248, 241, 227, 0.55);
  outline-offset: 3px;
}

body.is-landing #scroll-to-top {
  display: none !important;
}

.scroll-to-top-svg {
  display: block;
  width: 100%;
  height: 100%;
}

.scroll-to-top-disk {
  fill: rgba(21, 34, 56, 0.55);
}

.scroll-to-top:hover .scroll-to-top-disk {
  fill: rgba(21, 34, 56, 0.68);
}

/** Vòng chữ quay quanh tâm SVG (60,60); mũi tên vẽ sau nên đứng yên */
.scroll-top-ring-spin {
  transform-origin: 60px 60px;
  animation: scroll-top-ring-spin 12s linear infinite;
}

@keyframes scroll-top-ring-spin {
  from {
    transform: rotate(-92deg);
  }
  to {
    transform: rotate(268deg);
  }
}

@media (prefers-reduced-motion: reduce) {
  .scroll-top-ring-spin {
    animation: none;
    transform: rotate(-92deg);
  }
}

/** TextPath typography (SVG units) — Montserrat bám site */
.scroll-to-top-ring {
  font-family: Montserrat, ui-sans-serif, system-ui, sans-serif;
  font-weight: 600;
  font-size: 9.75px;
  letter-spacing: 0.08em;
  text-transform: none;
}

.scroll-to-top-arrow {
  opacity: 0.98;
}

@media (max-width: 520px) {
  .scroll-to-top-ring {
    font-size: 8.65px;
    letter-spacing: 0.065em;
  }
}

/* Globe + TIẾNG VIỆT | ENGLISH (header & footer) */
.lang-switch {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  font-family: var(--font-display), system-ui, sans-serif;
  font-size: clamp(0.68rem, 1.55vw, 0.78rem);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.lang-switch__globe {
  display: flex;
  color: rgba(248, 241, 227, 0.55);
  flex-shrink: 0;
}

.lang-switch__globe svg {
  display: block;
}

.lang-switch__sep {
  color: rgba(248, 241, 227, 0.35);
  font-weight: 400;
  user-select: none;
  padding: 0 0.1rem;
}

.lang-switch .lang-btn {
  margin: 0;
  padding: 0.15rem 0;
  border: none;
  border-radius: 0;
  background: none;
  color: rgba(248, 241, 227, 0.48);
  font: inherit;
  font-size: inherit;
  font-weight: 500;
  letter-spacing: inherit;
  text-transform: inherit;
  cursor: pointer;
  line-height: 1.25;
}

.lang-switch .lang-btn:hover {
  color: rgba(248, 241, 227, 0.88);
}

.lang-switch .lang-btn.is-active {
  color: var(--ink);
  font-weight: 700;
  background: none;
}

.lang-switch .lang-btn:focus-visible {
  outline: 2px solid rgba(248, 241, 227, 0.55);
  outline-offset: 3px;
  border-radius: 2px;
}

a {
  color: var(--accent);
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  display: flex;
  justify-content: center;
  align-items: stretch;
  padding: 0.55rem 1.25rem;
  background: var(--canvas-bg);
  color: var(--header-text);
  border-bottom: 1.25px solid #f8f1e3;
  box-shadow: none;
}

body:not(.is-landing) .site-header {
  border-bottom: none;
}

.site-header--stacked {
  padding-top: 0.45rem;
  padding-bottom: 0.4rem;
}

.site-header.is-hidden {
  display: none;
}

.header-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-start;
  align-items: center;
  gap: 0.5rem 1rem;
  width: 100%;
}

.header-inner--stacked {
  flex-direction: column;
  flex-wrap: nowrap;
  align-items: stretch;
  max-width: 1200px;
  margin: 0 auto;
  gap: 0.35rem;
}

@media (min-width: 641px) {
  body:not(.is-landing) .header-inner--stacked {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
    column-gap: 1rem;
    row-gap: 0.35rem;
    align-items: center;
  }

  body:not(.is-landing) .header-row--brand {
    display: contents;
  }

  body:not(.is-landing) .header-nav {
    grid-column: 1 / -1;
    display: grid;
    grid-template-columns: subgrid;
    justify-items: stretch;
  }

  body:not(.is-landing) .header-nav a[data-nav="home"] {
    justify-self: end;
    text-align: right;
  }

  body:not(.is-landing) .header-nav a[data-nav="concepts"] {
    justify-self: center;
    text-align: center;
  }

  body:not(.is-landing) .header-nav a[data-nav="about"] {
    justify-self: start;
    text-align: left;
  }

}


.header-row--brand {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
  align-items: center;
  gap: 0.65rem 1rem;
  width: 100%;
}

.header-cell {
  min-width: 0;
}

.header-cell--start {
  justify-self: start;
  align-self: center;
}

.header-cell--center {
  justify-self: center;
  align-self: center;
}

.header-cell--end {
  justify-self: end;
  align-self: center;
}

.site-header:not(.header--with-search) .header-cell--start .header-search {
  display: none;
}

.site-header:not(.header--with-search) .header-cell--start {
  visibility: hidden;
  pointer-events: none;
  width: 2rem;
  min-width: 2rem;
}

.header-search {
  position: relative;
  z-index: 2;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  box-sizing: border-box;
  width: fit-content;
  max-width: 100%;
  padding: 0.38rem 0.65rem;
  border-radius: 5px;
  border: 1px solid rgba(248, 241, 227, 0.28);
  background: rgba(255, 255, 255, 0.06);
  pointer-events: auto;
}

#header-search-overlay {
  position: fixed;
  inset: 0;
  z-index: 30;
  background: rgba(2, 6, 12, 0.72);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.16s ease-out;
}

body.header-search-overlay-open #header-search-overlay {
  opacity: 1;
  pointer-events: auto;
}

body:not(.is-landing) .header-search {
  width: 2rem;
  min-width: 2rem;
  height: 2rem;
  padding: 0.32rem;
  justify-content: center;
  gap: 0;
}

body:not(.is-landing) .header-search__icon {
  cursor: pointer;
}

.header-search-filter-clear {
  display: none;
  -webkit-appearance: none;
  appearance: none;
  align-items: center;
  justify-content: center;
  width: 1rem;
  height: 1rem;
  margin: 0 0 0 0.32rem;
  padding: 0;
  border: none;
  background: transparent;
  color: #ff4d57;
  font-size: 1.45rem;
  line-height: 1;
  cursor: pointer;
}

body:not(.is-landing) .header-cell--start.has-filter .header-search-filter-clear {
  display: inline-flex;
}

body:not(.is-landing) .header-search.is-open + .header-search-filter-clear {
  display: none !important;
}

body:not(.is-landing) .header-search__input {
  width: 0;
  min-width: 0;
  max-width: 0;
  opacity: 0;
  pointer-events: none;
}

body:not(.is-landing) .header-search.is-open {
  width: auto;
  min-width: min(18rem, 48vw);
  padding: 0.38rem 0.65rem;
  display: grid;
  grid-template-columns: 1rem minmax(0, 1fr) 1rem;
  column-gap: 0.45rem;
  justify-content: stretch;
  align-items: center;
  transform-origin: left center;
  animation: header-search-expand-inline 140ms cubic-bezier(0.22, 0.8, 0.2, 1);
  will-change: transform, opacity;
}

body:not(.is-landing) .header-search.is-closing {
  transform-origin: left center;
  animation: header-search-collapse-inline 120ms cubic-bezier(0.32, 0.1, 0.68, 1);
  will-change: transform, opacity;
}

body:not(.is-landing) .header-search.is-open .header-search__input {
  flex: 1 1 auto;
  min-width: 0;
  max-width: none;
  width: 100%;
  field-sizing: fixed;
  opacity: 1;
  pointer-events: auto;
}

@media (min-width: 641px) {
  .site-header.header--with-search .header-cell--start {
    min-width: 0;
    width: auto;
    max-width: 100%;
    justify-self: start;
  }
}

.header-search__icon {
  display: flex;
  flex-shrink: 0;
  align-items: center;
  justify-content: center;
  width: 1rem;
  height: 1rem;
  color: rgba(248, 241, 227, 0.55);
}

.header-search__icon svg {
  display: block;
  width: 100%;
  height: 100%;
}

.header-search__input {
  flex: 0 0 auto;
  -webkit-appearance: none;
  appearance: none;
  box-sizing: content-box;
  min-width: 0;
  max-width: 100%;
  margin: 0;
  padding: 0;
  border: none;
  background: transparent;
  color: var(--ink);
  font-family: var(--font-display), system-ui, sans-serif;
  font-size: clamp(0.72rem, 1.55vw, 0.82rem);
  font-weight: 500;
  letter-spacing: 0.04em;
  line-height: 1.2;
  outline: none;
}

.header-search__input::-webkit-search-cancel-button {
  -webkit-appearance: none;
  appearance: none;
  display: none;
}

.header-search__input::-webkit-search-decoration,
.header-search__input::-webkit-search-results-button,
.header-search__input::-webkit-search-results-decoration {
  -webkit-appearance: none;
  appearance: none;
  display: none;
}

.header-search__clear {
  display: none;
  align-items: center;
  justify-content: center;
  width: 1rem;
  height: 1rem;
  margin: 0;
  padding: 0;
  border: none;
  background: transparent;
  color: #ff4d57;
  font-size: 1.7rem;
  line-height: 1;
  cursor: pointer;
}

body:not(.is-landing) .header-search.is-open.has-value .header-search__clear {
  display: inline-flex;
}


@supports (field-sizing: content) {
  .header-search__input {
    width: auto;
    min-width: 19ch;
    max-width: min(36ch, 100%);
    field-sizing: content;
  }

  body:not(.is-landing) .header-search.is-open .header-search__input {
    width: 100%;
    min-width: 0;
    max-width: none;
    field-sizing: fixed;
  }
}

@media (max-width: 1024px) {
  body:not(.is-landing) .header-search.is-open {
    transform-origin: left center;
    animation: header-search-expand-from-lens 150ms cubic-bezier(0.2, 0.8, 0.2, 1);
    backface-visibility: hidden;
  }

  body:not(.is-landing) .header-search.is-closing {
    transform-origin: left center;
    animation: header-search-collapse-to-lens 140ms cubic-bezier(0.32, 0.1, 0.68, 1);
    backface-visibility: hidden;
  }
}

@keyframes header-search-expand-inline {
  from {
    opacity: 0.32;
    transform: scaleX(0.22);
  }
  to {
    opacity: 1;
    transform: scaleX(1);
  }
}

@keyframes header-search-collapse-inline {
  from {
    opacity: 1;
    transform: scaleX(1);
  }
  to {
    opacity: 0.2;
    transform: scaleX(0.22);
  }
}

@keyframes header-search-expand-from-lens {
  from {
    opacity: 0.35;
    transform: translate(-50%, -50%) scaleX(0.3) scaleY(0.86);
  }
  to {
    opacity: 1;
    transform: translate(-50%, -50%) scaleX(1) scaleY(1);
  }
}

@keyframes header-search-collapse-to-lens {
  from {
    opacity: 1;
    transform: translate(-50%, -50%) scaleX(1) scaleY(1);
  }
  to {
    opacity: 0.3;
    transform: translate(-50%, -50%) scaleX(0.3) scaleY(0.86);
  }
}

.header-search__input::placeholder {
  color: rgba(248, 241, 227, 0.45);
}

.header-search__input:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.header-lang-select {
  position: relative;
  z-index: 2;
  appearance: none;
  margin: 0;
  padding: 0.4rem 2rem 0.4rem 0.65rem;
  border-radius: 5px;
  border: 1px solid rgba(248, 241, 227, 0.28);
  background-color: rgba(255, 255, 255, 0.06);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%23c9bfa8' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.55rem center;
  background-size: 12px;
  color: var(--ink);
  font-family: var(--font-display), system-ui, sans-serif;
  font-size: clamp(0.72rem, 1.55vw, 0.82rem);
  font-weight: 600;
  letter-spacing: 0.12em;
  cursor: pointer;
  line-height: 1.2;
  pointer-events: auto;
}

.header-lang-select:focus-visible {
  outline: 2px solid rgba(248, 241, 227, 0.45);
  outline-offset: 2px;
}

@media (max-width: 640px) {
  :root {
    --header-bar-offset: 8.75rem;
  }

  body:not(.is-landing) .header-inner--stacked {
    display: flex;
    flex-direction: column;
  }

  body:not(.is-landing) .header-nav {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    width: min(32rem, 100%);
    margin-inline: auto;
    align-items: center;
    grid-column: unset;
  }

  body:not(.is-landing) .header-nav a[data-nav="home"],
  body:not(.is-landing) .header-nav a[data-nav="concepts"],
  body:not(.is-landing) .header-nav a[data-nav="about"] {
    min-width: 0;
  }

  body:not(.is-landing) .header-nav a[data-nav="home"] {
    justify-self: end;
    text-align: right;
  }

  body:not(.is-landing) .header-nav a[data-nav="concepts"] {
    justify-self: center;
    text-align: center;
  }

  body:not(.is-landing) .header-nav a[data-nav="about"] {
    justify-self: start;
    text-align: left;
  }

  .header-row--brand {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
    justify-content: stretch;
    align-items: center;
    gap: 0.4rem 0.55rem;
  }

  .header-cell--start {
    order: 1;
    justify-self: start;
    width: auto;
    max-width: none;
    margin-inline: 0;
  }

  .header-cell--center {
    order: 2;
    justify-self: center;
  }

  .header-cell--end {
    order: 3;
    justify-self: end;
    width: auto;
    display: flex;
    justify-content: flex-end;
  }

  .site-header:not(.header--with-search) .header-cell--start {
    display: block;
    visibility: hidden;
    pointer-events: none;
    width: 1.9rem;
    min-width: 1.9rem;
  }

  .header-search {
    max-width: 100%;
    justify-content: center;
  }

  body:not(.is-landing) .site-header .logo--header {
    height: clamp(48px, 20vw, 68px);
    max-width: min(200px, 46vw);
  }

  .header-logo-center {
    margin: 0.05rem 0;
  }

  body:not(.is-landing) .header-nav {
    margin-top: 0.2rem;
    padding-top: 0.45rem;
    padding-bottom: 0.45rem;
    font-size: clamp(0.66rem, 2.65vw, 0.8rem);
    gap: 0.3rem 0.9rem;
    width: 100%;
  }

  body:not(.is-landing) .header-nav a[data-nav] {
    white-space: nowrap;
  }

  @supports (field-sizing: content) {
    .header-search__input {
      min-width: 12ch;
      max-width: 100%;
    }
  }

  body:not(.is-landing) .header-search {
    width: 1.9rem;
    min-width: 1.9rem;
    height: 1.9rem;
    padding: 0.28rem;
  }

  body:not(.is-landing) .header-search.is-open {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    min-width: min(17rem, 92vw);
    width: min(17rem, 92vw);
    z-index: 42;
    box-shadow: 0 10px 22px rgba(6, 10, 19, 0.34);
  }

  body:not(.is-landing) .header-search.is-open .header-search__input {
    min-width: 10ch;
    max-width: min(20ch, 60vw);
  }
}

.header-logo-center {
  display: flex;
  justify-content: center;
  align-items: center;
  text-decoration: none;
  line-height: 0;
  margin: 0.15rem 0;
}

.header-logo-center:focus-visible {
  outline: 2px solid rgba(248, 241, 227, 0.45);
  outline-offset: 4px;
  border-radius: 6px;
}

.header-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: 0.35rem 1.35rem;
  padding: 0.55rem 0 0.2rem;
  margin-top: 0.1rem;
  border-top: 1px solid rgba(248, 241, 227, 0.14);
  font-family: var(--font-display), system-ui, sans-serif;
  font-size: clamp(0.68rem, 1.45vw, 0.76rem);
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

body:not(.is-landing) .header-nav {
  margin-top: 0.35rem;
  padding-top: 0.55rem;
  padding-bottom: 0.55rem;
  border-top: none;
  border-bottom: 0.9px solid rgba(248, 241, 227, 0.24);
  font-size: clamp(0.82rem, 2.05vw, 0.98rem);
  gap: 0.45rem 1.65rem;
}

.header-nav a {
  color: rgba(248, 241, 227, 0.68);
  text-decoration: none;
}

.header-nav a:hover {
  color: var(--ink);
  text-decoration: none;
}

.header-nav a.is-active {
  color: var(--ink);
  font-weight: 700;
}

.header-brand-stack {
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
  color: inherit;
  text-align: left;
}

.site-header .header-brand-stack:hover {
  text-decoration: none;
}

.site-header .header-brand-stack:focus-visible {
  outline: 2px solid rgba(248, 241, 227, 0.45);
  outline-offset: 4px;
  border-radius: 6px;
}

.site-header .header-brand-stack:hover .header-title {
  color: rgba(248, 241, 227, 0.82);
}

.site-header img.logo {
  height: 44px;
  width: auto;
  max-width: min(180px, 42vw);
  object-fit: contain;
  display: block;
  flex-shrink: 0;
}

.site-header img.logo.logo--rounded {
  border-radius: 50%;
}

.site-header .logo--header {
  height: 52px;
  max-width: min(220px, 52vw);
}

@media (min-width: 640px) {
  .site-header .logo--header {
    height: 62px;
    max-width: min(260px, 48vw);
  }
}

body:not(.is-landing) .site-header .logo--header {
  height: clamp(76px, 10vw, 96px);
  max-width: min(300px, 52vw);
}

@media (min-width: 900px) {
  body:not(.is-landing) .site-header .logo--header {
    height: clamp(88px, 8.5vw, 108px);
    max-width: min(340px, 44vw);
  }
}

/* Điện thoại xoay ngang: header gọn, không chiếm ~1/3 chiều cao màn hình */
@media (orientation: landscape) and (max-height: 520px) and (max-width: 1024px) {
  :root {
    --header-bar-offset: 4.4rem;
  }

  .site-header.site-header--stacked {
    padding: 0.2rem 0.65rem 0.15rem;
  }

  .header-inner--stacked {
    gap: 0.18rem;
  }

  body:not(.is-landing) .site-header .logo--header {
    height: clamp(28px, 18vh, 38px);
    max-width: min(96px, 18vw);
  }

  .header-logo-center {
    margin: 0;
  }

  .header-search {
    padding: 0.2rem 0.45rem;
  }

  .header-lang-select {
    padding: 0.22rem 1.65rem 0.22rem 0.45rem;
    font-size: 0.7rem;
  }

  body:not(.is-landing) .header-row--brand {
    grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr);
    justify-content: stretch;
    gap: 0.35rem 0.6rem;
  }

  body:not(.is-landing) .header-cell--start {
    grid-column: 1;
    justify-self: start;
    width: auto;
  }

  .site-header:not(.header--with-search) .header-cell--start {
    width: 1.75rem;
    min-width: 1.75rem;
  }

  body:not(.is-landing) .header-cell--center {
    grid-column: 2;
    justify-self: center;
    width: auto;
  }

  body:not(.is-landing) .header-cell--end {
    grid-column: 3;
    justify-self: end;
    width: auto;
  }

  body:not(.is-landing) .header-search {
    width: 1.75rem;
    min-width: 1.75rem;
    height: 1.75rem;
    padding: 0.24rem;
  }

  body:not(.is-landing) .header-search.is-open {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    min-width: min(13rem, 72vw);
    width: min(13rem, 72vw);
    z-index: 42;
    box-shadow: 0 8px 18px rgba(6, 10, 19, 0.3);
  }

  body:not(.is-landing) .header-search.is-open .header-search__input {
    min-width: 8ch;
    max-width: min(14ch, 34vw);
  }

  body:not(.is-landing) .header-nav {
    margin-top: 0.08rem;
    padding: 0.18rem 0 0.16rem;
    gap: 0.2rem 0.85rem;
    font-size: clamp(0.58rem, 1.85vh, 0.7rem);
  }
}

@media (orientation: landscape) and (max-height: 520px) and (max-width: 640px) {
  :root {
    --header-bar-offset: 4.75rem;
  }

  .header-row--brand {
    gap: 0.22rem;
  }
}

.landing-logo-link {
  display: block;
  width: fit-content;
  max-width: 100%;
  margin: 0 auto 0.35rem;
  line-height: 0;
  text-decoration: none;
}

.landing-logo-link:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 4px;
  border-radius: 4px;
}

.site-header .header-title {
  margin: 0;
  max-width: min(28rem, calc(100vw - 12rem));
  font-size: clamp(1.35rem, 3.6vw, 1.85rem);
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: none;
  line-height: 1.2;
  color: inherit;
  font-family: var(--font-display);
}

/* ─── Route morph (landing → Concept / About): overlay + spacer scroll ─── */
body.route-morph-active {
  overflow: hidden;
  overscroll-behavior: none;
  touch-action: none;
}

/** Safari: giữ header trên một composite layer ổn định khi morph kết thúc */
body.route-morph-active .site-header {
  transform: translateZ(0);
  backface-visibility: hidden;
  opacity: 1 !important;
  visibility: visible !important;
  transition: none !important;
}

.route-morph-overlay {
  position: fixed;
  inset: 0;
  z-index: 150;
  background: var(--canvas-bg);
  pointer-events: none;
  visibility: hidden;
  opacity: 0;
}

/* Mở lớp: hiện để transition opacity (tránh display:none / [hidden] → không fade được) */
.route-morph-overlay.is-route-morph-open {
  visibility: visible;
}

.route-morph-overlay.is-route-morph-open.is-route-morph-fade-in {
  opacity: 1;
  transition: opacity 0.3s var(--ease-page-entrance);
}

.route-morph-logo-el {
  display: block;
  margin: 0;
  padding: 0;
  border: none;
  border-radius: 50%;
  opacity: 0;
  transition: opacity 0.28s var(--ease-page-entrance) 0.04s;
}

/** Compositing ổn định khi JS cập nhật left/top/width/height mỗi frame */
body.route-morph-active .route-morph-logo-el {
  transform: translateZ(0);
  backface-visibility: hidden;
}

.route-morph-overlay.is-route-morph-open.is-route-morph-fade-in .route-morph-logo-el {
  opacity: 1;
}

.route-morph-hint {
  position: fixed;
  left: 50%;
  bottom: max(1.5rem, env(safe-area-inset-bottom));
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.18rem;
  color: rgba(248, 241, 227, 0.9);
  font-family: var(--font-display), system-ui, sans-serif;
  font-size: clamp(0.9rem, 2.1vw, 1.08rem);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.28s var(--ease-page-entrance);
}

.route-morph-hint__arrow {
  display: flex;
  justify-content: center;
  line-height: 0;
  color: rgba(248, 241, 227, 0.88);
  animation: route-morph-hint-bob 1.1s ease-in-out infinite alternate;
}

.route-morph-hint__arrow-svg {
  display: block;
  width: 11px;
  height: min(6.75rem, 21vh);
}

@keyframes route-morph-hint-bob {
  from {
    transform: translateY(0);
  }
  to {
    transform: translateY(8px);
  }
}

.route-morph-spacer {
  width: 100%;
  flex-shrink: 0;
  min-height: clamp(380px, 92dvh, 720px);
  pointer-events: none;
}

@media (orientation: landscape) and (max-height: 520px) {
  .route-morph-spacer {
    min-height: clamp(280px, 120vh, 520px);
  }
}

body.route-morph-pending #view-overview .page-inner,
body.route-morph-pending #view-about .page-inner {
  visibility: hidden;
}

@media (prefers-reduced-motion: reduce) {
  .route-morph-overlay,
  .route-morph-spacer {
    display: none !important;
  }

  body.route-morph-pending #view-overview .page-inner,
  body.route-morph-pending #view-about .page-inner {
    visibility: visible;
  }
}

body.route-morph-overlay-visible .scroll-to-top {
  visibility: hidden;
  opacity: 0;
  pointer-events: none;
}

.landing-inner.is-morph-exit .landing-wordmark,
.landing-inner.is-morph-exit .landing-lead,
.landing-inner.is-morph-exit .landing-actions {
  opacity: 0;
  transform: translateY(8px);
  pointer-events: none;
  transition:
    opacity 0.52s var(--ease-page-entrance),
    transform 0.52s var(--ease-page-entrance);
}

.boot-status {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0;
  padding: 1rem;
  font-family: system-ui, sans-serif;
  font-size: 1rem;
  color: var(--muted);
  background: var(--canvas-bg);
}

.boot-status.error {
  color: var(--ink);
}

.boot-status[hidden] {
  display: none;
}

.view-landing {
  min-height: 0;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  justify-content: flex-start;
  padding: 0;
  background: var(--canvas-bg);
}

.view-landing[hidden] {
  display: none !important;
}

/* Hai trang dọc: trang 1 hero; trang 2 = banner + footer (cùng một nhịp cuộn). */
.landing-snap-viewport {
  box-sizing: border-box;
  width: 100%;
  flex: 1 1 auto;
  align-self: stretch;
  min-height: 0;
  height: auto;
  max-height: none;
  overflow-x: hidden;
  overflow-y: auto;
  overscroll-behavior-y: contain;
  -webkit-overflow-scrolling: touch;
}

@media (prefers-reduced-motion: no-preference) {
  body.is-landing .landing-snap-viewport {
    scroll-snap-type: y mandatory;
    scroll-behavior: smooth;
  }
}

@media (prefers-reduced-motion: reduce) {
  body.is-landing .landing-snap-viewport {
    scroll-snap-type: none;
    scroll-behavior: auto;
  }
}

.landing-inner {
  display: flex;
  flex-direction: column;
  width: 100%;
  max-width: min(72rem, 100%);
  margin-inline: auto;
  text-align: center;
}

/* Màn đầu: chỉ logo + wordmark + mô tả + nav, luôn ít nhất một viewport (mobile ngang/dọc + desktop) */
.landing-hero {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  box-sizing: border-box;
  width: 100%;
  min-height: 100vh;
  min-height: 100svh;
  min-height: 100dvh;
  padding: max(0.75rem, env(safe-area-inset-top)) 1.25rem max(1rem, env(safe-area-inset-bottom));
}

body.is-landing .landing-hero {
  scroll-snap-align: start;
  scroll-snap-stop: normal;
}

/* Trang 2: một snap block — đỉnh là banner; cuộn tiếp trong cùng khối thấy footer */
body.is-landing .landing-page-2 {
  box-sizing: border-box;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  width: 100%;
  min-height: 100vh;
  min-height: 100svh;
  min-height: 100dvh;
  padding-top: max(0.35rem, env(safe-area-inset-top));
  padding-bottom: max(0.35rem, env(safe-area-inset-bottom));
  scroll-snap-align: start;
  scroll-snap-stop: normal;
}

body.is-landing .landing-slide-page:has(#landing-banner-rail:not([hidden])) {
  flex: 1 1 auto;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  justify-content: center;
  min-height: 0;
  padding: 0 0 max(0.35rem, env(safe-area-inset-bottom));
}

body.is-landing .landing-slide-page:not(:has(#landing-banner-rail:not([hidden]))) {
  flex: 0 0 auto;
  min-height: 0;
  padding: 0;
}

/* Footer full-bleed: margin calc theo parent width (không dùng left 50% — sẽ lệch trong .landing-inner hẹp). */
body.is-landing .landing-footer-host {
  flex: 0 0 auto;
  width: 100vw;
  max-width: none;
  position: relative;
  margin-left: calc(50% - 50vw);
  margin-right: calc(50% - 50vw);
  margin-top: clamp(2rem, 5.5vw, 3.25rem);
}

/**
 * Điện thoại / màn hẹp: banner sát safe-area (Dynamic Island), footer kéo lên gần banner.
 * (Trước đây justify-content: center tạo khoảng trống đều trên–dưới trong trang 2.)
 */
@media (max-width: 1024px) {
  body.is-landing .landing-page-2 {
    padding-top: env(safe-area-inset-top, 0px);
    padding-bottom: max(0.25rem, env(safe-area-inset-bottom, 0px));
  }

  body.is-landing .landing-slide-page:has(#landing-banner-rail:not([hidden])) {
    justify-content: flex-start;
    padding-bottom: max(0.25rem, env(safe-area-inset-bottom, 0px));
  }

  body.is-landing .landing-footer-host {
    margin-top: clamp(0.45rem, 2.2vw, 0.95rem);
  }

  body.is-landing .site-footer-main {
    padding-top: 0.95rem;
  }

  body.is-landing .landing-below {
    justify-content: flex-start;
  }
}

.landing-below {
  width: 100%;
  max-width: none;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  justify-content: center;
}

@keyframes landing-fade-up {
  from {
    opacity: 0;
    transform: translateY(1.15rem);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (prefers-reduced-motion: no-preference) {
  .view-landing:not([hidden]) .landing-hero > .landing-logo-link {
    opacity: 0;
    animation: landing-fade-up 0.9s var(--ease-page-entrance) 0.05s both;
  }

  .view-landing:not([hidden]) .landing-hero > .landing-wordmark {
    opacity: 0;
    animation: landing-fade-up 0.9s var(--ease-page-entrance) 0.22s both;
  }

  .view-landing:not([hidden]) .landing-hero > .landing-lead {
    opacity: 0;
    animation: landing-fade-up 0.9s var(--ease-page-entrance) 0.4s both;
  }

  .view-landing:not([hidden]) .landing-hero > .landing-actions {
    opacity: 0;
    animation: landing-fade-up 0.9s var(--ease-page-entrance) 0.58s both;
  }
}

@media (prefers-reduced-motion: reduce) {
  .view-landing .landing-hero > .landing-logo-link,
  .view-landing .landing-hero > .landing-wordmark,
  .view-landing .landing-hero > .landing-lead,
  .view-landing .landing-hero > .landing-actions {
    animation: none;
    opacity: 1;
    transform: none;
  }
}

.landing-logo {
  width: auto;
  max-width: min(920px, 88vw);
  max-height: min(42svh, 46dvh, 440px);
  height: auto;
  object-fit: contain;
  margin: 0;
  display: block;
}

/* Khối tiêu đề (giống sans đậm ảnh 2), tách khỏi đoạn mô tả bên dưới */
.landing-wordmark {
  margin: 0 auto 0;
  padding: 0 0.5rem 1.35rem;
  text-align: center;
  border-bottom: 1px solid rgba(248, 241, 227, 0.28);
  max-width: 40rem;
}

.landing-wordmark-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.9rem, 5.5vw, 2.85rem);
  letter-spacing: 0.12em;
  line-height: 1.05;
  text-transform: uppercase;
  color: var(--landing-hero-text);
}

.landing-wordmark-sub {
  margin: 0.3rem 0 0;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: clamp(0.98rem, 2.5vw, 1.18rem);
  letter-spacing: 0.08em;
  line-height: 1.35;
  color: var(--landing-hero-text);
}

.landing-lead {
  margin: 1.25rem auto 1.5rem;
  max-width: 46rem;
  font-size: clamp(1.1rem, 3.2vw, 1.85rem);
  line-height: 1.55;
  color: var(--landing-hero-text);
}

.landing-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 1.5rem;
  justify-content: center;
  align-items: stretch;
}

.landing-actions--cta {
  gap: 1.35rem clamp(2.85rem, 11vw, 5.75rem);
}

.landing-nav-btn {
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
  font-size: clamp(0.9rem, 2.6vw, 1.08rem);
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--landing-hero-text);
  background: transparent;
  border: none;
  border-bottom: none;
  padding: 0.45rem 0.2rem 0.55rem;
  cursor: pointer;
  text-decoration: underline;
  text-decoration-color: rgba(248, 241, 227, 0.88);
  text-underline-offset: 0.2em;
  text-decoration-thickness: 1px;
  display: inline-block;
  text-align: center;
  transition: color 0.15s;
}

.landing-actions--cta .landing-nav-btn {
  font-size: clamp(1.05rem, 3.1vw, 1.35rem);
  font-weight: 700;
  letter-spacing: 0.16em;
  padding: 0.55rem 0.35rem 0.65rem;
}

.landing-nav-btn:hover {
  color: rgba(248, 241, 227, 0.78);
  text-decoration: underline;
  text-decoration-color: rgba(248, 241, 227, 0.65);
}

@media (max-width: 520px) {
  .landing-actions {
    flex-direction: row;
    flex-wrap: nowrap;
    justify-content: center;
    align-items: center;
    gap: clamp(0.35rem, 2vw, 0.75rem) clamp(1.5rem, 9vw, 2.85rem);
  }

  .landing-actions--cta {
    gap: clamp(0.35rem, 2vw, 0.75rem) clamp(1.5rem, 9vw, 2.85rem);
  }

  .landing-actions--cta .landing-nav-btn {
    font-size: clamp(0.7rem, 3.4vw, 0.95rem);
    letter-spacing: 0.09em;
    padding: 0.38rem 0.12rem 0.48rem;
  }
}

/** Điện thoại ngang (chiều cao thấp): giảm vw-based type + logo để không tràn/mất chữ; banner thấp hơn cho còn chỗ footer. */
@media (orientation: landscape) and (max-height: 520px) {
  body.is-landing .landing-hero {
    justify-content: center;
    padding-top: max(0.3rem, env(safe-area-inset-top));
    padding-bottom: max(0.35rem, env(safe-area-inset-bottom));
  }

  .landing-logo-link {
    margin-bottom: 0.15rem;
  }

  .landing-logo {
    width: auto;
    max-width: min(280px, 40vw);
    max-height: min(20svh, 110px);
  }

  .landing-wordmark {
    padding: 0 0.5rem 0.5rem;
    max-width: min(40rem, 94vw);
  }

  .landing-wordmark-title {
    font-size: clamp(0.95rem, 3.4vw, 1.55rem);
    letter-spacing: 0.08em;
    line-height: 1.08;
  }

  .landing-wordmark-sub {
    font-size: clamp(0.7rem, 1.95vw, 0.9rem);
    margin-top: 0.12rem;
    line-height: 1.25;
  }

  .landing-lead {
    margin: 0.45rem auto 0.6rem;
    max-width: min(44rem, 94vw);
    font-size: clamp(0.72rem, 2.05vw, 0.98rem);
    line-height: 1.45;
  }

  .landing-actions--cta {
    gap: 0.45rem 1.85rem;
    margin-top: 0.1rem;
    flex-wrap: wrap;
  }

  .landing-actions--cta .landing-nav-btn {
    font-size: clamp(0.62rem, 1.75vw, 0.82rem);
    letter-spacing: 0.08em;
    padding: 0.3rem 0.14rem 0.38rem;
  }

  .landing-banner-scroller {
    --landing-banner-h: min(50dvh, 58svh, 380px);
    min-height: min(max(140px, 32svh), var(--landing-banner-h));
    max-height: var(--landing-banner-h);
    overscroll-behavior-x: contain;
  }

  /* Cho phép trang 2 nở theo nội dung để cuộn được xuống footer ở màn ngang thấp */
  body.is-landing .landing-slide-page:has(#landing-banner-rail:not([hidden])) {
    flex: 0 0 auto;
    flex-grow: 0;
  }

  body.is-landing .landing-page-2 {
    padding-bottom: max(0.2rem, env(safe-area-inset-bottom, 0px));
  }

  /* Snap đáy footer để không bị hút ngược về đầu banner khi chạm cuối trang 2 */
  body.is-landing .landing-footer-host {
    scroll-snap-align: end;
    scroll-snap-stop: normal;
  }
}

@media (orientation: landscape) and (max-height: 520px) and (max-width: 1024px) {
  .page-inner {
    padding: 0.55rem 0.75rem 1.15rem;
  }

  .grid {
    grid-template-columns: repeat(auto-fill, minmax(132px, 1fr));
    gap: 0.5rem;
  }

  .grid button.thumb {
    border-radius: 3px;
  }
}

@media (orientation: landscape) and (max-height: 520px) {
  .site-footer-bar-inner {
    grid-template-columns: 1fr;
    justify-items: center;
    text-align: center;
    gap: 0.38rem;
  }

  .site-footer-bar-spacer {
    display: none;
  }

  .site-footer-lang {
    grid-column: 1;
    justify-self: center;
  }

  .site-footer-copy {
    grid-column: 1;
    justify-self: center;
    text-align: center;
    max-width: 100%;
  }
}

/* Banner ngang: full-bleed bằng margin calc(50% - 50vw) — căn đúng từ parent có max-width. */
.landing-banner-rail {
  flex-shrink: 0;
  box-sizing: border-box;
  width: 100vw;
  max-width: none;
  position: relative;
  margin-left: calc(50% - 50vw);
  margin-right: calc(50% - 50vw);
  padding-inline: clamp(0.85rem, 4vw, 3rem);
}

.landing-banner-viewport {
  position: relative;
  width: 100%;
  max-width: var(--footer-inner-max);
  margin-inline: auto;
  overflow: hidden;
  border-radius: 0;
  background: var(--canvas-bg);
}

/* Ảnh kéo full ngang ô slide (như chiều rộng nội dung footer); object-fit giữ tỉ lệ trong max-height. */
.landing-banner-slide-media {
  position: relative;
  box-sizing: border-box;
  width: 100%;
  height: 100%;
  max-width: 100%;
  max-height: 100%;
  min-height: 0;
  min-width: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0;
}

.landing-banner-slide-media > .landing-banner-slide__img {
  display: block;
  width: 100%;
  height: 100%;
  /* Cover: luôn lấp full khung (mũi tên dính vào ảnh); contain để chỉnh tay nếu cần tránh crop. */
  object-fit: cover;
  object-position: center;
}

/* Mũi tên mảnh: ẩn mặc định; desktop hover / focus; mobile khi có class is-chrome-reveal (vuốt ngang) */
.landing-banner-arrow {
  position: absolute;
  top: 50%;
  /* Trên thumb + vuốt, luôn nổi trên scroller */
  z-index: 8;
  transform: translateY(-50%);
  width: auto;
  min-width: 1.75rem;
  height: auto;
  min-height: 2.5rem;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0.15rem 0.2rem;
  border: none;
  border-radius: 0;
  background: transparent;
  color: rgba(248, 241, 227, 0.92);
  cursor: pointer;
  opacity: 0;
  pointer-events: none;
  transition:
    color 0.18s ease,
    opacity 0.22s ease;
  -webkit-tap-highlight-color: transparent;
}

@media (hover: hover) and (pointer: fine) {
  .landing-banner-viewport:hover .landing-banner-arrow:not(:disabled) {
    opacity: 1;
    pointer-events: auto;
  }
}

.landing-banner-viewport.is-chrome-reveal .landing-banner-arrow:not(:disabled) {
  opacity: 1;
  pointer-events: auto;
}

.landing-banner-viewport:focus-within .landing-banner-arrow:not(:disabled) {
  opacity: 1;
  pointer-events: auto;
}

.landing-banner-arrow:hover:not(:disabled) {
  color: #fff;
}

.landing-banner-arrow:focus-visible {
  outline: 2px solid rgba(248, 241, 227, 0.55);
  outline-offset: 2px;
  opacity: 1;
  pointer-events: auto;
}

.landing-banner-arrow:disabled {
  opacity: 0 !important;
  pointer-events: none !important;
  cursor: default;
}

.landing-banner-arrow--prev {
  left: clamp(0.25rem, 1.5vw, 0.65rem);
}

.landing-banner-arrow--next {
  right: clamp(0.25rem, 1.5vw, 0.65rem);
}

.landing-banner-arrow__svg {
  display: block;
  line-height: 0;
  pointer-events: none;
  filter: drop-shadow(0 0 10px rgba(10, 18, 32, 0.9)) drop-shadow(0 1px 18px rgba(10, 18, 32, 0.75));
}

.landing-banner-arrow__svg svg {
  display: block;
  width: clamp(16px, 3.2vw, 22px);
  height: auto;
  max-height: min(3.5rem, 14svh);
}

.landing-banner-scroller {
  --landing-banner-h: min(72dvh, 78svh, 820px);
  position: relative;
  z-index: 1;
  display: flex;
  flex-flow: row nowrap;
  gap: 0;
  width: 100%;
  height: var(--landing-banner-h);
  min-height: min(max(220px, 38svh), var(--landing-banner-h));
  max-height: var(--landing-banner-h);
  overflow-x: auto;
  overflow-y: hidden;
  scroll-snap-type: x mandatory;
  scroll-behavior: smooth;
  scrollbar-width: none;
  -ms-overflow-style: none;
  border: none;
  cursor: grab;
  /* pan-x một mình chặn cuộn dọc lên trang cha trên mobile; cho phép cả dọc để cuộn #landing-snap-viewport */
  touch-action: pan-x pan-y;
  -webkit-overflow-scrolling: touch;
  overscroll-behavior-x: contain;
  background: var(--canvas-bg);
}

.landing-banner-scroller:active {
  cursor: grabbing;
}

.landing-banner-scroller::-webkit-scrollbar {
  display: none;
}

@media (prefers-reduced-motion: reduce) {
  .landing-banner-scroller {
    scroll-behavior: auto;
  }
}

/**
 * Điện thoại / tablet dọc: khung xem không cao như máy dọc (tránh ô “đứng” + cover làm crop mất cánh ảnh ngang).
 * 16∶9 = dải ngang ổn định; contain = không cắt nội dung (letterbox navy nếu cần).
 */
@media (max-width: 1024px) and (orientation: portrait) {
  body.is-landing .landing-slide-page:has(#landing-banner-rail:not([hidden])) {
    flex: 0 0 auto;
    flex-grow: 0;
  }

  /** Giữ mandatory snap nhưng dễ “đậu” đáy cuộn sau footer + safe-area. */
  body.is-landing .landing-snap-viewport {
    scroll-padding-bottom: max(0.5rem, env(safe-area-inset-bottom, 0px));
  }

  /** 100dvw + margin tương ứng: full-bleed ổn định hơn 100vw (viewport động / safe-area). */
  .landing-banner-rail {
    width: 100vw;
    width: 100dvw;
    margin-left: calc(50% - 50vw);
    margin-right: calc(50% - 50vw);
    margin-left: calc(50% - 50dvw);
    margin-right: calc(50% - 50dvw);
    padding-inline: env(safe-area-inset-left, 0px) env(safe-area-inset-right, 0px);
  }

  .landing-banner-viewport {
    max-width: none;
    width: 100%;
    margin-inline: 0;
  }

  .landing-banner-scroller {
    height: auto;
    aspect-ratio: 16 / 9;
    min-height: unset;
    max-height: unset;
    /* Ghi đè biến cũ tránh một số engine dùng chung với height cố định */
    --landing-banner-h: auto;
  }

  .landing-banner-slide-media > .landing-banner-slide__img {
    /* Cover = tràn hai cạnh ngang ô 16∶9 (có thể crop dải trên/dưới ảnh rất ngang). */
    object-fit: cover;
    object-position: center;
  }
}

.landing-banner-slide {
  flex: 0 0 100%;
  width: 100%;
  min-width: 0;
  height: 100%;
  min-height: 0;
  scroll-snap-align: start;
  /* normal: không bắt dừng từng slide khi smooth wrap 4→1 (always gây “ghé” t2/t3 và dot nhảy). */
  scroll-snap-stop: normal;
  display: flex;
  align-items: center;
  justify-content: center;
  box-sizing: border-box;
  padding: 0;
  margin: 0;
  background: var(--canvas-bg);
}

/* Grid + stretch: con lấp full slide; ảnh bên trong vẫn contain + căn giữa nhờ flex trên .landing-banner-slide-media. */
.landing-banner-slide__link {
  display: grid;
  width: 100%;
  height: 100%;
  min-width: 0;
  min-height: 0;
  padding: 0;
  text-decoration: none;
  color: inherit;
  outline-offset: 2px;
  position: relative;
}

.landing-banner-slide__link:focus-visible {
  outline: 2px solid rgba(248, 241, 227, 0.55);
}

.landing-banner-dots {
  position: absolute;
  left: 50%;
  bottom: clamp(0.35rem, 2vw, 0.75rem);
  transform: translateX(-50%);
  z-index: 5;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: 0.45rem;
  margin: 0;
  padding: 0;
  border-radius: 0;
  background: transparent;
  pointer-events: auto;
}

.landing-banner-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  border: 1px solid rgba(248, 241, 227, 0.42);
  background: transparent;
  padding: 0;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease;
}

.landing-banner-dot:hover {
  border-color: rgba(248, 241, 227, 0.65);
}

.landing-banner-dot.is-active {
  background: rgba(248, 241, 227, 0.88);
  border-color: rgba(248, 241, 227, 0.88);
}

.page-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 1.25rem 3rem;
  background: var(--canvas-bg);
  min-height: calc(100vh - var(--header-bar-offset));
}

.page-inner--overview {
  max-width: min(1080px, 100%);
  padding-inline: clamp(0.85rem, 3vw, 1.75rem);
}

@media (max-width: 640px) {
  .page-inner--overview {
    padding-inline: clamp(0.55rem, 2.5vw, 1rem);
    padding-top: 0.65rem;
  }
}

.view-overview .page-title {
  text-align: center;
  color: rgba(248, 241, 227, 0.96);
  margin-bottom: 1.35rem;
}

.view-overview[hidden],
.view-concept[hidden],
.view-about[hidden] {
  display: none !important;
}

#view-about {
  background-color: var(--canvas-bg);
  min-height: calc(100vh - var(--header-bar-offset));
}

.about-page {
  padding-top: 1.25rem;
  padding-bottom: 3rem;
}

.about-title {
  margin: 0 0 1rem;
  font-size: clamp(1.35rem, 3.2vw, 2rem);
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--ink);
}

.about-lead {
  margin: 0;
  max-width: 42rem;
  font-size: clamp(1.1rem, 2.5vw, 1.4rem);
  line-height: 1.6;
  color: rgba(248, 241, 227, 0.9);
}

.back-link {
  display: inline-block;
  margin-bottom: 1rem;
  font-family: system-ui, sans-serif;
  font-size: clamp(1rem, 2.5vw, 1.2rem);
  color: var(--accent);
}

.page-title {
  margin: 0 0 1rem;
  font-size: clamp(0.95rem, 2.3vw, 1.15rem);
  font-family: system-ui, sans-serif;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

@keyframes overview-card-in {
  from {
    opacity: 0;
    transform: translateY(0.65rem) scale(0.98);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@media (prefers-reduced-motion: no-preference) {
  .view-concept:not([hidden]) .page-inner > .back-link {
    opacity: 0;
    animation: landing-fade-up 0.6s var(--ease-page-entrance) 0.04s both;
  }

  .view-overview:not([hidden]) .page-inner > .page-title,
  .view-concept:not([hidden]) .page-inner > .concept-head {
    opacity: 0;
    animation: landing-fade-up 0.6s var(--ease-page-entrance) 0.12s both;
  }

  .view-overview:not([hidden]) .overview-cards .concept-card {
    opacity: 0;
    animation-name: overview-card-in;
    animation-duration: 0.55s;
    animation-timing-function: var(--ease-page-entrance);
    animation-delay: calc(0.18s + (var(--card-stagger, 0) * 42ms));
    animation-fill-mode: both;
  }

  .view-concept:not([hidden]) .grid button.thumb {
    opacity: 0;
    animation: overview-card-in 0.52s var(--ease-page-entrance)
      calc(0.2s + var(--thumb-stagger, 0) * 36ms) both;
  }
}

@media (prefers-reduced-motion: reduce) {
  .view-overview .page-inner > .page-title,
  .view-overview .overview-cards .concept-card,
  .view-concept .page-inner > .back-link,
  .view-concept .page-inner > .concept-head,
  .view-concept .grid button.thumb {
    animation: none;
    opacity: 1;
    transform: none;
  }
}

.overview-empty {
  grid-column: 1 / -1;
  margin: 0;
  padding: 2rem 1rem 1.25rem;
  text-align: center;
  font-family: var(--font-display), system-ui, sans-serif;
  font-size: clamp(0.85rem, 2vw, 1rem);
  font-weight: 500;
  color: rgba(248, 241, 227, 0.72);
}

.overview-cards {
  display: grid;
  width: 100%;
  min-width: 0;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(0.5rem, 2.2vw, 0.95rem);
}

@media (min-width: 720px) {
  .overview-cards {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: clamp(1rem, 2vw, 1.25rem);
  }
}

.concept-card {
  margin: 0;
}

.concept-card-inner {
  width: 100%;
  min-width: 0;
  padding: 0;
  border: none;
  border-radius: 0;
  overflow: visible;
  cursor: pointer;
  text-align: center;
  background: transparent;
  box-shadow: none;
  transition: transform 0.28s var(--ease-page-entrance);
}

.concept-card-inner:hover {
  transform: translateY(-3px);
}

.concept-card-inner:active {
  transform: translateY(-1px);
}

.concept-card-inner:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

.concept-card-visual {
  position: relative;
  width: 100%;
  min-width: 0;
  aspect-ratio: 3 / 4;
  overflow: hidden;
  border-radius: clamp(12px, 2.2vw, 16px);
  box-shadow: 0 2px 14px rgba(0, 0, 0, 0.2);
  transition: box-shadow 0.28s var(--ease-page-entrance);
}

.concept-card-inner:hover .concept-card-visual,
.concept-card-inner:focus-visible .concept-card-visual {
  box-shadow: 0 6px 26px rgba(0, 0, 0, 0.32);
}

.concept-card-cover-layer {
  display: block;
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0;
  z-index: 1;
  pointer-events: none;
  transition: opacity 0.52s var(--ease-page-entrance);
}

.concept-card-cover-layer.is-visible {
  opacity: 1;
  z-index: 2;
  transform: scale(1);
  transition:
    opacity 0.52s var(--ease-page-entrance),
    transform 0.45s var(--ease-page-entrance);
}

@media (prefers-reduced-motion: no-preference) {
  .view-overview .concept-card-inner:hover .concept-card-cover-layer.is-visible,
  .view-overview .concept-card-inner:focus-visible .concept-card-cover-layer.is-visible {
    transform: scale(1.015);
  }
}

@media (prefers-reduced-motion: reduce) {
  .view-overview .concept-card-cover-layer.is-visible {
    transform: none;
  }
}

.concept-card-title {
  margin: 0;
  padding: 0.55rem 0.35rem 0;
  font-family: var(--font-display), system-ui, sans-serif;
  font-size: clamp(0.78rem, 1.45vw, 0.92rem);
  font-weight: 600;
  letter-spacing: 0.04em;
  line-height: 1.35;
  text-align: center;
  background: transparent;
  color: rgba(248, 241, 227, 0.9);
}

@media (max-width: 640px) {
  .concept-card-visual {
    border-radius: clamp(8px, 2vw, 13px);
  }

  .concept-card-title {
    font-size: clamp(0.62rem, 2.8vw, 0.78rem);
    padding: 0.38rem 0.12rem 0;
    line-height: 1.3;
  }
}

.concept-head {
  margin-bottom: 1rem;
}

.concept-head h2 {
  margin: 0;
  font-size: clamp(2rem, 4.5vw, 2.5rem);
  font-weight: 500;
  color: var(--concept-name);
  text-align: center;
}

.grid {
  width: 100%;
  max-width: min(880px, 100%);
  margin-inline: auto;
  column-width: 180px;
  column-gap: 0.35rem;
}

@media (min-width: 600px) {
  .grid {
    column-width: 220px;
    column-gap: 0.4rem;
  }
}

.grid button.thumb {
  position: relative;
  display: block;
  width: 100%;
  break-inside: avoid;
  -webkit-column-break-inside: avoid;
  margin: 0 0 0.35rem;
  padding: 0;
  border: none;
  border-radius: 0;
  overflow: hidden;
  cursor: zoom-in;
  background: var(--surface);
  box-shadow: none;
}

.grid button.thumb img {
  width: 100%;
  height: auto;
  object-fit: contain;
  display: block;
  transition: transform 0.35s ease;
}

@media (min-width: 600px) {
  .grid button.thumb {
    margin-bottom: 0.4rem;
  }
}

.grid button.thumb:hover img {
  transform: scale(1.04);
}

.grid button.thumb:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.concept-related {
  margin-top: clamp(1.3rem, 3.2vw, 2.4rem);
}

.concept-related__title {
  margin: 0 0 clamp(0.55rem, 1.8vw, 0.95rem);
  font-family: var(--font-display), system-ui, sans-serif;
  font-size: clamp(0.86rem, 1.95vw, 1.05rem);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: rgba(248, 241, 227, 0.9);
}

.concept-related-cards {
  max-width: min(1060px, 100%);
}

.status,
.error {
  padding: 2rem;
  text-align: center;
  color: var(--muted);
  font-size: 1.15rem;
}

.error {
  color: var(--ink);
}

/* Lightbox (tối riêng, không dùng palette sáng của trang) */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(5, 8, 7, 0.92);
  padding: 1rem;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.2s ease;
  color: var(--ink);
  will-change: opacity;
  transform: translateZ(0);
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
}

.lightbox.is-open {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.lightbox.is-closing {
  visibility: visible;
  pointer-events: none;
}

.lightbox-inner {
  position: relative;
  max-width: min(96vw, 1400px);
  max-height: 92vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.35rem;
}

.lightbox-toolbar {
  display: flex;
  gap: 0.35rem;
  align-items: center;
  z-index: 5;
  font-family: system-ui, sans-serif;
}

.lightbox-toolbar button {
  min-width: 2.25rem;
  padding: 0.35rem 0.5rem;
  font-size: 0.9rem;
  border: 1px solid #3d3d38;
  border-radius: 4px;
  background: rgba(30, 28, 26, 0.92);
  color: var(--ink);
  cursor: pointer;
}

.lightbox-toolbar button:hover {
  border-color: var(--ink);
  color: var(--ink);
}

.lightbox-viewport {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: min(96vw, 1200px);
  height: min(78vh, 900px);
  overflow: hidden;
  touch-action: none;
  cursor: grab;
  border-radius: 4px;
  background: #0a0f0d;
  box-shadow: 0 12px 48px rgba(0, 0, 0, 0.55);
}

.lightbox-viewport.is-dragging {
  cursor: grabbing;
}

.lightbox-zoom-wrap {
  flex-shrink: 0;
  transform: translate(0px, 0px) scale(1);
  transform-origin: center center;
  will-change: transform;
}

.lightbox-zoom-wrap img {
  display: block;
  max-width: min(92vw, 1100px);
  max-height: min(74vh, 820px);
  width: auto;
  height: auto;
  object-fit: contain;
  border-radius: 2px;
  user-select: none;
  -webkit-user-drag: none;
}

.lightbox-zoom-wrap img.is-enter-from-right {
  animation: lightbox-slide-in-right 220ms cubic-bezier(0.22, 0.8, 0.2, 1);
}

.lightbox-zoom-wrap img.is-enter-from-left {
  animation: lightbox-slide-in-left 220ms cubic-bezier(0.22, 0.8, 0.2, 1);
}

@keyframes lightbox-slide-in-right {
  from {
    opacity: 0.38;
    transform: translate3d(28px, 0, 0) scale(0.99);
  }
  to {
    opacity: 1;
    transform: translate3d(0, 0, 0) scale(1);
  }
}

@keyframes lightbox-slide-in-left {
  from {
    opacity: 0.38;
    transform: translate3d(-28px, 0, 0) scale(0.99);
  }
  to {
    opacity: 1;
    transform: translate3d(0, 0, 0) scale(1);
  }
}

.lightbox-hint {
  margin: 0;
  font-size: 0.8rem;
  color: var(--ink);
  font-family: system-ui, sans-serif;
  text-align: center;
  max-width: 28rem;
}

.lightbox .caption {
  font-size: 1rem;
  color: var(--ink);
}

.lightbox .caption .lightbox-caption-title {
  color: var(--ink);
}

.lightbox .caption .lightbox-caption-count {
  color: var(--ink);
}

.lightbox .close {
  position: absolute;
  top: -2.5rem;
  right: 0;
  font-family: system-ui, sans-serif;
  font-size: 0.85rem;
  background: transparent;
  border: 1px solid #4a4a44;
  padding: 0.35rem 0.75rem;
  border-radius: 4px;
  cursor: pointer;
  color: var(--ink);
}

.lightbox .close:hover {
  border-color: var(--ink);
  color: var(--ink);
}

.lightbox .nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid #4a4a44;
  background: rgba(30, 28, 26, 0.88);
  color: var(--ink);
  font-size: 1.25rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  line-height: 1;
  z-index: 7;
  opacity: 1;
}

.lightbox .nav:hover {
  border-color: var(--ink);
  color: var(--ink);
}

.lightbox .nav.prev {
  left: -3.25rem;
}

.lightbox .nav.next {
  right: -3.25rem;
}

@media (max-width: 900px) {
  .lightbox .nav.prev {
    left: 0.25rem;
  }
  .lightbox .nav.next {
    right: 0.25rem;
  }
  .lightbox .nav {
    width: 46px;
    height: 46px;
    font-size: 1.35rem;
    background: rgba(24, 22, 20, 0.92);
  }
  .lightbox .close {
    top: 0.25rem;
    right: 0.25rem;
  }
  .lightbox-viewport {
    width: 94vw;
    height: min(70vh, 560px);
  }
}

@media (prefers-reduced-motion: reduce) {
  .lightbox-zoom-wrap img.is-enter-from-right,
  .lightbox-zoom-wrap img.is-enter-from-left {
    animation: none;
  }
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}