/* ============================================================
   环球中心 · 共享站点样式 /assets/site.css
   丝路枢纽：经纬网格 · 章节编号 · 珠宝色带 · 硬阴影编辑体
   ============================================================ */

/* ---------- 1. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }

body, h1, h2, h3, h4, h5, p, figure, blockquote, dl, dd, ul, ol { margin: 0; }

ul, ol { padding: 0; }

ul[class], ol[class] { list-style: none; }

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

button { font: inherit; color: inherit; background: none; border: 0; }

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

table { border-collapse: collapse; }

/* ---------- 2. Tokens ---------- */
:root {
  --blue: #0A4C8C;
  --teal: #063B3A;
  --gold: #D9A441;
  --snow: #F6F8F7;
  --oasis: #2E8B7A;
  --wine: #7A2239;
  --indigo: #2B2A6B;
  --ink: #1B1F24;
  --gravel: #C9C2B4;
  --sky: #CFE3F2;

  --font-head: "HarmonyOS Sans SC", "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --font-body: "HarmonyOS Sans SC", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, "Liberation Mono", monospace;

  --header-h: 66px;
  --gutter: clamp(1.15rem, 4.5vw, 2.75rem);
  --maxw: 1240px;
  --ease: cubic-bezier(.22, .61, .36, 1);

  --hair: rgba(246, 248, 247, .22);
  --hair-dark: rgba(27, 31, 36, .16);

  --shadow-hard: 8px 8px 0 rgba(27, 31, 36, .14);
  --shadow-blue: 10px 10px 0 rgba(10, 76, 140, .18);
  --shadow-gold: 5px 5px 0 rgba(217, 164, 65, .55);
}

@media (min-width: 960px) {
  :root { --header-h: 80px; }
}

/* ---------- 3. Base typography ---------- */
body {
  background: var(--snow);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: clamp(1rem, .96rem + .2vw, 1.125rem);
  line-height: 1.75;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4 {
  font-family: var(--font-head);
  font-weight: 900;
  line-height: 1.06;
  letter-spacing: -.02em;
}

h1 { font-size: clamp(2.8rem, 6vw, 5.5rem); }
h2 { font-size: clamp(2rem, 3.6vw, 3.2rem); }
h3 { font-size: clamp(1.3rem, 1.5vw, 1.6rem); font-weight: 800; line-height: 1.3; }
h4 { font-size: 1.05rem; font-weight: 800; line-height: 1.4; letter-spacing: 0; }

p { max-width: 68ch; }

strong { font-weight: 700; }

::selection { background: var(--gold); color: var(--ink); }

[id] { scroll-margin-top: calc(var(--header-h) + 1.25rem); }

:focus-visible {
  outline: 3px solid var(--ink);
  outline-offset: 3px;
}

.site-header:not(.is-solid) :focus-visible,
.site-footer :focus-visible,
.section--ink :focus-visible,
.section--blue :focus-visible {
  outline-color: var(--gold);
}

/* ---------- 4. Utilities ---------- */
.container {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

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

.mono {
  font-family: var(--font-mono);
  letter-spacing: .08em;
  font-variant-numeric: tabular-nums;
}

.rule {
  height: 2px;
  border: 0;
  background: currentColor;
  opacity: .18;
  margin-block: clamp(1.5rem, 3vw, 2.5rem);
}

/* ---------- 5. Skip link ---------- */
.skip-link {
  position: fixed;
  top: -120px;
  left: var(--gutter);
  z-index: 999;
  padding: .7rem 1.15rem;
  background: var(--gold);
  color: var(--ink);
  font-family: var(--font-head);
  font-weight: 800;
  font-size: .9375rem;
  border: 2px solid var(--ink);
  box-shadow: 4px 4px 0 rgba(27, 31, 36, .35);
  transition: top .2s var(--ease);
}

.skip-link:focus { top: .75rem; }

/* ---------- 6. Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  padding: .72rem 1.15rem;
  font-family: var(--font-head);
  font-weight: 800;
  font-size: .9375rem;
  line-height: 1.2;
  letter-spacing: .02em;
  border: 2px solid var(--ink);
  background: var(--ink);
  color: var(--snow);
  box-shadow: var(--shadow-gold);
  cursor: pointer;
  transition: transform .18s var(--ease), box-shadow .18s var(--ease), background-color .18s var(--ease), color .18s var(--ease);
}

.btn:hover { transform: translate(-2px, -2px); box-shadow: 7px 7px 0 rgba(217, 164, 65, .75); }
.btn:active { transform: translate(1px, 1px); box-shadow: 2px 2px 0 rgba(217, 164, 65, .6); }

.btn--gold {
  background: var(--gold);
  color: var(--ink);
  border-color: var(--ink);
  box-shadow: 5px 5px 0 rgba(27, 31, 36, .3);
}
.btn--gold:hover { box-shadow: 7px 7px 0 rgba(27, 31, 36, .45); }

.btn--blue {
  background: var(--blue);
  color: var(--snow);
  border-color: var(--ink);
  box-shadow: var(--shadow-gold);
}

.btn--ghost {
  background: transparent;
  color: inherit;
  border-color: currentColor;
  box-shadow: none;
}
.btn--ghost:hover { background: rgba(217, 164, 65, .16); box-shadow: none; transform: translate(-1px, -1px); }

/* ---------- 7. Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 120;
  isolation: isolate;
  color: var(--snow);
  background: transparent;
  border-bottom: 1px solid var(--hair);
  transition: background-color .35s var(--ease), color .35s var(--ease), border-color .35s var(--ease), box-shadow .35s var(--ease);
}

.site-header::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background: linear-gradient(180deg, rgba(6, 59, 58, .82) 0%, rgba(6, 59, 58, .38) 62%, rgba(6, 59, 58, 0) 100%);
  transition: opacity .35s var(--ease);
  pointer-events: none;
}

.site-header.is-solid {
  background: rgba(246, 248, 247, .985);
  color: var(--ink);
  border-bottom: 2px solid var(--blue);
  box-shadow: 0 3px 0 0 rgba(217, 164, 65, .85);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
}

.site-header.is-solid::before { opacity: 0; }

.scroll-progress {
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 3px;
  background: var(--gold);
  transform: scaleX(0);
  transform-origin: 0 50%;
  z-index: 3;
  pointer-events: none;
}

.site-header__inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: clamp(.75rem, 2vw, 2rem);
  min-height: var(--header-h);
  padding-block: .5rem;
}

/* Brand */
.brand {
  display: inline-flex;
  align-items: center;
  gap: .7rem;
  min-width: 0;
}

.brand__mark {
  position: relative;
  display: grid;
  place-items: center;
  flex: 0 0 auto;
  width: 2.55rem;
  height: 2.55rem;
  border: 2px solid var(--gold);
  color: var(--gold);
  font-family: var(--font-mono);
  font-size: .8125rem;
  font-weight: 700;
  letter-spacing: .06em;
  transition: color .35s var(--ease), border-color .35s var(--ease);
}

.brand__mark::after {
  content: "";
  position: absolute;
  right: -4px;
  bottom: -4px;
  width: 8px;
  height: 8px;
  background: var(--gold);
}

.brand__text { display: flex; flex-direction: column; min-width: 0; }

.brand__line {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: 1rem;
  line-height: 1.2;
  letter-spacing: .01em;
  white-space: nowrap;
}

.brand__descriptor {
  font-family: var(--font-body);
  font-size: .6875rem;
  letter-spacing: .12em;
  line-height: 1.5;
  opacity: .72;
  white-space: nowrap;
}

.is-solid .brand__mark { color: var(--blue); border-color: var(--blue); }

/* Nav */
.site-nav { display: block; justify-self: center; }

.site-nav__list {
  display: flex;
  align-items: center;
  gap: clamp(.25rem, 1.2vw, 1.35rem);
  flex-wrap: nowrap;
}

.site-nav__link {
  display: inline-flex;
  align-items: baseline;
  gap: .35rem;
  padding: .45rem .15rem;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: .9375rem;
  letter-spacing: .02em;
  white-space: nowrap;
  border-bottom: 2px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.site-nav__index {
  font-family: var(--font-mono);
  font-size: .625rem;
  font-weight: 500;
  letter-spacing: .08em;
  opacity: .62;
}

.site-nav__link:hover,
.site-nav__link:focus-visible {
  color: var(--gold);
  border-bottom-color: var(--gold);
}

.site-nav__link[aria-current="page"] {
  color: var(--gold);
  border-bottom-color: var(--gold);
}

.is-solid .site-nav__link:hover,
.is-solid .site-nav__link:focus-visible,
.is-solid .site-nav__link[aria-current="page"] {
  color: var(--blue);
  border-bottom-color: var(--blue);
}

/* Actions */
.header-actions {
  display: flex;
  align-items: center;
  gap: .85rem;
  justify-self: end;
}

.header-note {
  font-family: var(--font-mono);
  font-size: .6875rem;
  letter-spacing: .1em;
  padding: .3rem .5rem;
  border: 1px solid currentColor;
  opacity: .78;
  white-space: nowrap;
}

.header-cta {
  padding: .58rem .9rem;
  font-size: .875rem;
  white-space: nowrap;
}

/* Mobile toggle */
.nav-toggle {
  position: relative;
  display: none;
  width: 2.9rem;
  height: 2.6rem;
  border: 2px solid currentColor;
  background: transparent;
  cursor: pointer;
  flex: 0 0 auto;
}

.nav-toggle__bar {
  position: absolute;
  left: 50%;
  width: 1.2rem;
  height: 2px;
  background: currentColor;
  transform: translateX(-50%);
  transition: transform .26s var(--ease), opacity .18s var(--ease), top .26s var(--ease);
}

.nav-toggle__bar:nth-child(1) { top: calc(50% - 7px); }
.nav-toggle__bar:nth-child(2) { top: calc(50% - 1px); }
.nav-toggle__bar:nth-child(3) { top: calc(50% + 5px); }

.site-header[data-open] .nav-toggle__bar:nth-child(1) {
  top: calc(50% - 1px);
  transform: translateX(-50%) rotate(45deg);
}
.site-header[data-open] .nav-toggle__bar:nth-child(2) { opacity: 0; }
.site-header[data-open] .nav-toggle__bar:nth-child(3) {
  top: calc(50% - 1px);
  transform: translateX(-50%) rotate(-45deg);
}

.nav-toggle[aria-expanded="true"] { color: var(--gold); }

/* ---------- 8. Footer ---------- */
.site-footer {
  position: relative;
  background: var(--teal);
  color: var(--snow);
  border-top: 3px solid var(--ink);
  overflow: hidden;
}

.footer-meridian {
  height: 10px;
  background: linear-gradient(
    90deg,
    var(--gold) 0 16%,
    var(--blue) 16% 44%,
    var(--oasis) 44% 60%,
    var(--wine) 60% 76%,
    var(--indigo) 76% 100%
  );
}

.site-footer__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(2rem, 5vw, 3.25rem);
  padding-block: clamp(2.75rem, 6vw, 4.5rem);
}

.footer-brand { display: flex; flex-direction: column; align-items: flex-start; gap: 1rem; }

.brand--footer .brand__line { font-size: 1.05rem; }
.brand--footer .brand__descriptor { opacity: .64; }

.footer-tagline {
  font-family: var(--font-head);
  font-weight: 900;
  font-size: clamp(1.8rem, 3.6vw, 2.75rem);
  line-height: 1.08;
  letter-spacing: -.02em;
  margin-top: .35rem;
  border-bottom: 3px solid var(--gold);
  padding-bottom: .5rem;
  display: inline-block;
}

.footer-lede {
  font-size: .9375rem;
  line-height: 1.8;
  color: rgba(246, 248, 247, .76);
  max-width: 34ch;
}

.footer-coord {
  font-family: var(--font-mono);
  font-size: .6875rem;
  letter-spacing: .14em;
  color: var(--sky);
  opacity: .78;
}

.footer-cta { margin-top: .35rem; }

.footer-col { display: flex; flex-direction: column; gap: .9rem; }

.footer-col__title {
  font-family: var(--font-mono);
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--gold);
  padding-bottom: .6rem;
  border-bottom: 1px solid var(--hair);
}

.footer-links { display: grid; gap: .55rem; }

.footer-link {
  display: inline-block;
  font-size: .9375rem;
  line-height: 1.6;
  color: rgba(246, 248, 247, .84);
  border-bottom: 1px solid transparent;
  transition: color .2s var(--ease), border-color .2s var(--ease);
}

.footer-link:hover,
.footer-link:focus-visible {
  color: var(--gold);
  border-bottom-color: var(--gold);
}

.footer-contact { display: grid; gap: .95rem; }

.footer-contact__item { display: flex; flex-direction: column; gap: .2rem; }

.footer-contact__label {
  font-family: var(--font-mono);
  font-size: .6875rem;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--gold);
}

.footer-contact__value {
  font-size: .9375rem;
  font-weight: 600;
  line-height: 1.6;
  color: var(--snow);
  overflow-wrap: anywhere;
}

.footer-note {
  font-size: .8125rem;
  line-height: 1.75;
  color: rgba(246, 248, 247, .62);
  border-top: 1px solid var(--hair);
  padding-top: .9rem;
  max-width: 40ch;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: .65rem 1.5rem;
  padding-block: 1.15rem 1.4rem;
  border-top: 1px solid var(--hair);
}

.footer-legal {
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: .06em;
  color: rgba(246, 248, 247, .66);
  max-width: none;
}

.footer-legal__links {
  display: flex;
  flex-wrap: wrap;
  gap: .4rem 1.25rem;
  font-size: .8125rem;
}

.footer-legal__links .footer-link { font-size: .8125rem; }

/* ---------- 9. Shared layout components ---------- */
.section {
  position: relative;
  padding-block: clamp(3.25rem, 7vw, 6.5rem);
}

.section--snow { background: var(--snow); color: var(--ink); }
.section--ink { background: var(--teal); color: var(--snow); }
.section--blue { background: var(--blue); color: var(--snow); }

.section--ink p,
.section--blue p { color: rgba(246, 248, 247, .84); }

.section__head {
  display: grid;
  gap: 1rem;
  max-width: 66ch;
  margin-bottom: clamp(1.5rem, 3.5vw, 2.75rem);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: .6rem;
  font-family: var(--font-mono);
  font-size: .75rem;
  font-weight: 600;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--gold);
}

.eyebrow::before {
  content: "";
  width: 2.2rem;
  height: 2px;
  background: var(--gold);
  flex: 0 0 auto;
}

.section-num {
  font-family: var(--font-mono);
  font-size: clamp(2.4rem, 6vw, 4.5rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -.03em;
  color: var(--gold);
  font-variant-numeric: tabular-nums;
}

.grid-2 {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(1.5rem, 4vw, 3.5rem);
}

@media (min-width: 820px) {
  .grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

.panel {
  border: 3px solid var(--ink);
  background: var(--snow);
  color: var(--ink);
  padding: clamp(1.25rem, 3vw, 2rem);
  box-shadow: var(--shadow-hard);
}

.aside-note {
  border-left: 4px solid var(--gold);
  padding: .2rem 0 .2rem 1rem;
  font-size: .9375rem;
  line-height: 1.75;
  color: rgba(27, 31, 36, .78);
}

.section--ink .aside-note,
.section--blue .aside-note { color: rgba(246, 248, 247, .8); }

.tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: .6875rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  padding: .22rem .55rem;
  border: 2px solid currentColor;
  color: var(--oasis);
}

.section--ink .tag,
.section--blue .tag { color: var(--gold); }

/* Image container foundation (页面阶段放入 img 即用) */
.media-frame {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 10;
  border: 3px solid var(--ink);
  background:
    repeating-linear-gradient(90deg, rgba(10, 76, 140, .13) 0 1px, transparent 1px 56px),
    repeating-linear-gradient(0deg, rgba(10, 76, 140, .13) 0 1px, transparent 1px 56px),
    linear-gradient(135deg, var(--sky) 0%, var(--snow) 58%, #E5EBE6 100%);
  box-shadow: var(--shadow-blue);
}

.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.media-frame--wide { aspect-ratio: 21 / 9; }
.media-frame--tall { aspect-ratio: 3 / 4; }

.media-frame--ink {
  border-color: var(--gold);
  background:
    repeating-linear-gradient(90deg, rgba(217, 164, 65, .16) 0 1px, transparent 1px 56px),
    repeating-linear-gradient(0deg, rgba(217, 164, 65, .16) 0 1px, transparent 1px 56px),
    linear-gradient(135deg, var(--teal) 0%, var(--indigo) 100%);
  box-shadow: 10px 10px 0 rgba(217, 164, 65, .22);
}

.media-frame__caption {
  position: absolute;
  left: 0;
  bottom: 0;
  padding: .35rem .6rem;
  background: var(--ink);
  color: var(--snow);
  font-family: var(--font-mono);
  font-size: .6875rem;
  letter-spacing: .12em;
}

/* Breadcrumbs */
.breadcrumbs { padding-block: clamp(.9rem, 2vw, 1.4rem); }

.breadcrumbs__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .45rem;
  font-family: var(--font-mono);
  font-size: .75rem;
  letter-spacing: .08em;
  color: rgba(27, 31, 36, .62);
}

.breadcrumbs__list > li + li::before {
  content: "/";
  margin-right: .45rem;
  opacity: .5;
}

.breadcrumbs a {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.breadcrumbs [aria-current="page"] { color: var(--ink); font-weight: 600; }

/* Hero foundation：页面首个深色区块加 data-hero，即与透明头部叠合 */
[data-hero] {
  position: relative;
  margin-top: calc(-1 * var(--header-h));
  padding-top: calc(var(--header-h) + clamp(2rem, 6vw, 4rem));
  background-color: var(--teal);
  color: var(--snow);
  overflow: hidden;
}

/* ---------- 10. Motion ---------- */
.reveal-ready [data-reveal] {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity .7s var(--ease), transform .7s var(--ease);
}

.reveal-ready [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }

  .reveal-ready [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .btn:hover,
  .btn:active { transform: none; }

  .scroll-progress { transition: none; }
}

/* ---------- 11. Breakpoints ---------- */
@media (max-width: 1180px) {
  .header-note { display: none; }
}

@media (max-width: 1040px) and (min-width: 960px) {
  .header-cta { display: none; }
}

@media (max-width: 959px) {
  .site-header__inner {
    grid-template-columns: minmax(0, 1fr) auto;
    gap: .75rem;
  }

  .nav-toggle { display: block; }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: none;
    justify-self: stretch;
    background: var(--teal);
    color: var(--snow);
    border-top: 2px solid var(--gold);
    border-bottom: 3px solid var(--gold);
    padding: .35rem var(--gutter) 1.35rem;
    max-height: calc(100dvh - var(--header-h));
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
  }

  .site-header[data-open] .site-nav {
    display: block;
    animation: navPanel .28s var(--ease) both;
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }

  .site-nav__item + .site-nav__item { border-top: 1px solid var(--hair); }

  .site-nav__link {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    padding: .95rem 0;
    font-size: 1.0625rem;
    border-bottom: 0;
  }

  .site-nav__link:hover,
  .site-nav__link:focus-visible,
  .site-nav__link[aria-current="page"] {
    color: var(--gold);
    border-bottom-color: transparent;
  }

  .is-solid .site-nav__link:hover,
  .is-solid .site-nav__link:focus-visible,
  .is-solid .site-nav__link[aria-current="page"] {
    color: var(--snow);
  }

  .site-nav__link[aria-current="page"] .site-nav__index { opacity: 1; color: var(--gold); }

  .brand__descriptor { font-size: .625rem; letter-spacing: .08em; }
}

@keyframes navPanel {
  from { opacity: 0; transform: translateY(-10px); }
  to { opacity: 1; transform: none; }
}

@media (max-width: 559px) {
  .header-cta { display: none; }
  .brand__mark { width: 2.3rem; height: 2.3rem; font-size: .75rem; }
  .brand__line { font-size: .9375rem; }
  .brand__descriptor { font-size: .59375rem; }
  .footer-bottom { flex-direction: column; align-items: flex-start; }
}

@media (min-width: 600px) {
  .site-footer__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-brand { grid-column: 1 / -1; }
  .footer-col--contact { grid-column: 1 / -1; }
}

@media (min-width: 1024px) {
  .site-footer__grid {
    grid-template-columns: 1.55fr .72fr .82fr 1.15fr;
    gap: 2.5rem 3rem;
  }
  .footer-brand,
  .footer-col--contact { grid-column: auto; }
}