/* =============================================================
   皇家国际荟 · 全站共享样式
   File: /assets/site.css
   ============================================================= */

/* ---------- 1. Reset & Tokens ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --royal-blue: #0B1E3F;
  --gold: #C9A227;
  --crimson: #6B2D2D;
  --jade: #1F4D3A;
  --ivory: #F4F1EB;
  --mist: #7A8794;
  --light-gold: #E8D9A0;
  --steel: #2A3A5E;
  --cut: 16px;
  --font-serif: "Songti SC", "SimSun", "Noto Serif SC", serif;
  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --font-mono: "SF Mono", "Cascadia Code", "Consolas", "JetBrains Mono", monospace;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --section-pad: clamp(48px, 7vw, 88px);
}

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

[hidden] {
  display: none !important;
}

body {
  min-height: 100vh;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  font-weight: 400;
  color: var(--royal-blue);
  background-color: var(--ivory);
  background-image:
    linear-gradient(rgba(201, 162, 39, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(201, 162, 39, 0.035) 1px, transparent 1px);
  background-size: 48px 48px;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

body.no-scroll {
  overflow: hidden;
}

body.nav-open::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 115;
  background: rgba(5, 12, 28, 0.56);
  -webkit-backdrop-filter: blur(2px);
  backdrop-filter: blur(2px);
}

/* ---------- 2. Typography ---------- */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-serif);
  font-weight: 700;
  line-height: 1.3;
  color: var(--royal-blue);
  text-wrap: balance;
}

p {
  text-wrap: pretty;
}

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

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

ul,
ol {
  list-style: none;
}

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

:focus {
  outline: none;
}

:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 3px;
}

/* ---------- 3. Layout Primitives ---------- */
.container {
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: 24px;
}

.section {
  padding-block: var(--section-pad);
}

.section-head {
  max-width: 760px;
  margin-bottom: 36px;
  position: relative;
  padding-left: 18px;
}

.section-head::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: linear-gradient(180deg, var(--gold), transparent);
}

.section-head--center {
  margin-inline: auto;
  text-align: center;
  padding-left: 0;
}

.section-head--center::before {
  left: 50%;
  transform: translateX(-50%);
  top: auto;
  bottom: auto;
  top: -14px;
  width: 56px;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--gold), transparent);
}

.section-kicker {
  display: block;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.16em;
  color: var(--gold);
  text-transform: uppercase;
  margin-bottom: 8px;
}

.section-title {
  font-family: var(--font-serif);
  font-size: clamp(26px, 3.4vw, 38px);
  font-weight: 700;
  line-height: 1.3;
  color: var(--royal-blue);
  letter-spacing: 0.04em;
}

.section-desc {
  margin-top: 12px;
  color: var(--steel);
  font-size: 15px;
  line-height: 1.8;
}

.grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

.deco-line {
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(201, 162, 39, 0.55), transparent);
  border: 0;
  margin: 28px 0;
}

/* ---------- 4. Buttons & Tags ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 24px;
  font-size: 15px;
  font-weight: 500;
  letter-spacing: 0.04em;
  line-height: 1.5;
  text-align: center;
  cursor: pointer;
  border: 1px solid transparent;
  clip-path: polygon(12px 0, 100% 0, 100% calc(100% - 12px), calc(100% - 12px) 100%, 0 100%, 0 12px);
  transition: background-color 0.3s, color 0.3s, border-color 0.3s;
}

.btn-gold {
  background: linear-gradient(135deg, var(--gold), #A5821B);
  color: var(--ivory);
}

.btn-gold:hover {
  background: linear-gradient(135deg, var(--light-gold), var(--gold));
  color: var(--royal-blue);
}

.btn-ghost {
  background: transparent;
  color: var(--gold);
  border-color: rgba(201, 162, 39, 0.6);
}

.btn-ghost:hover {
  background: rgba(201, 162, 39, 0.1);
}

.btn-small {
  padding: 6px 16px;
  font-size: 13px;
}

.btn-block {
  display: flex;
  width: 100%;
}

.tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  padding: 4px 10px;
  color: var(--ivory);
  background: var(--crimson);
  clip-path: polygon(6px 0, 100% 0, 100% calc(100% - 6px), calc(100% - 6px) 100%, 0 100%, 0 6px);
}

.tag--gold {
  background: var(--gold);
  color: var(--royal-blue);
}

.tag--green {
  background: var(--jade);
}

/* ---------- 5. Breadcrumb ---------- */
.breadcrumb {
  padding: 18px 0 0;
  font-size: 14px;
  color: var(--mist);
}

.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.breadcrumb-list li {
  display: flex;
  align-items: center;
  gap: 6px;
}

.breadcrumb-list li:not(:last-child)::after {
  content: "/";
  color: var(--gold);
  font-family: var(--font-mono);
}

.breadcrumb a {
  color: var(--steel);
}

.breadcrumb a:hover {
  color: var(--gold);
}

.breadcrumb [aria-current="page"] {
  color: var(--royal-blue);
  font-weight: 500;
}

/* ---------- 6. Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 200;
  background: var(--royal-blue);
  color: var(--ivory);
  border-bottom: 1px solid rgba(201, 162, 39, 0.45);
}

.site-header::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(201, 162, 39, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(201, 162, 39, 0.05) 1px, transparent 1px);
  background-size: 44px 44px;
  pointer-events: none;
}

.site-header::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: linear-gradient(90deg, transparent 4%, var(--gold) 50%, transparent 96%);
  opacity: 0.7;
  pointer-events: none;
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0;
  background: linear-gradient(90deg, var(--gold), var(--light-gold));
  box-shadow: 0 0 12px rgba(201, 162, 39, 0.55);
  z-index: 150;
  pointer-events: none;
}

.header-utility {
  position: relative;
  z-index: 1;
  background: rgba(4, 12, 28, 0.4);
  border-bottom: 1px solid rgba(201, 162, 39, 0.14);
}

.header-utility-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 34px;
  font-size: 12.5px;
}

.legacy-link {
  position: relative;
  padding-left: 18px;
  color: var(--light-gold);
  transition: color 0.3s;
}

.legacy-link::before {
  content: "❖";
  position: absolute;
  left: 0;
  color: var(--gold);
  font-size: 11px;
}

.legacy-link:hover {
  color: var(--gold);
}

.header-utility-note {
  color: rgba(201, 162, 39, 0.6);
  letter-spacing: 0.04em;
  white-space: nowrap;
}

.header-main {
  position: relative;
  z-index: 1;
}

.header-box {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 74px;
}

/* ---------- 7. Brand ---------- */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex-shrink: 0;
}

.brand-seal {
  position: relative;
  width: 42px;
  height: 42px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transform: rotate(45deg);
  border: 1px solid rgba(201, 162, 39, 0.65);
  background: linear-gradient(135deg, rgba(201, 162, 39, 0.16), rgba(201, 162, 39, 0.02));
}

.brand-seal::after {
  content: "";
  position: absolute;
  inset: 4px;
  border: 1px solid rgba(201, 162, 39, 0.3);
}

.brand-seal i {
  font-style: normal;
  font-family: var(--font-serif);
  font-size: 19px;
  font-weight: 700;
  color: var(--gold);
  transform: rotate(-45deg);
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}

.brand-name {
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 700;
  letter-spacing: 0.1em;
  background: linear-gradient(115deg, #A5821B 0%, #C9A227 20%, #F7EBC3 42%, #C9A227 65%, #8C6D14 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: var(--gold);
  -webkit-text-fill-color: transparent;
}

.brand-en {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.34em;
  color: rgba(201, 162, 39, 0.6);
  text-transform: uppercase;
}

/* ---------- 8. Navigation ---------- */
.nav-toggle {
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px;
  border: 1px solid rgba(201, 162, 39, 0.4);
  color: var(--gold);
  z-index: 130;
  clip-path: polygon(8px 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%, 0 8px);
}

.nav-toggle-lines,
[data-nav-toggle] .nav-toggle-lines {
  position: relative;
  display: block;
  width: 20px;
  height: 14px;
}

.nav-toggle-lines::before,
.nav-toggle-lines::after,
.nav-toggle-lines i {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  background: currentColor;
  transition: transform 0.3s var(--ease), top 0.3s var(--ease), opacity 0.3s;
}

.nav-toggle-lines::before {
  top: 0;
}

.nav-toggle-lines i {
  top: 6px;
}

.nav-toggle-lines::after {
  top: 12px;
}

body.nav-open .nav-toggle-lines::before {
  top: 6px;
  transform: rotate(45deg);
}

body.nav-open .nav-toggle-lines i {
  opacity: 0;
}

body.nav-open .nav-toggle-lines::after {
  top: 6px;
  transform: rotate(-45deg);
}

.nav-toggle-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
}

.site-nav,
[data-nav] {
  position: relative;
  z-index: 1;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.nav-item {
  position: relative;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 8px 14px;
  color: rgba(244, 241, 235, 0.78);
  font-size: 15px;
  letter-spacing: 0.05em;
  position: relative;
  transition: color 0.3s, background-color 0.3s;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 2px;
  height: 2px;
  background: var(--gold);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.3s var(--ease);
}

.nav-link:hover {
  color: var(--gold);
}

.nav-link:hover::after {
  transform: scaleX(1);
}

.nav-link-title {
  line-height: 1.3;
}

.nav-link-index {
  font-family: var(--font-mono);
  font-size: 11px;
  color: rgba(201, 162, 39, 0.7);
}

.nav-link[aria-current="page"] {
  color: var(--gold);
  background: rgba(201, 162, 39, 0.08);
  clip-path: polygon(8px 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%, 0 8px);
}

.nav-link[aria-current="page"]::after {
  transform: scaleX(1);
}

.nav-drawer-head,
.nav-drawer-foot {
  display: none;
}

/* ---------- 9. Footer ---------- */
.site-footer {
  position: relative;
  background: var(--royal-blue);
  color: rgba(244, 241, 235, 0.72);
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(201, 162, 39, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(201, 162, 39, 0.045) 1px, transparent 1px);
  background-size: 52px 52px;
  pointer-events: none;
}

.footer-main {
  position: relative;
  z-index: 1;
  padding-block: clamp(52px, 7vw, 88px) 40px;
  border-top: 2px solid rgba(201, 162, 39, 0.5);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2.2fr 1fr 1fr 1.6fr;
  gap: 36px;
}

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

.footer-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 18px;
}

.footer-seal {
  width: 38px;
  height: 38px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transform: rotate(45deg);
  border: 1px solid rgba(201, 162, 39, 0.6);
  background: linear-gradient(135deg, rgba(201, 162, 39, 0.14), rgba(201, 162, 39, 0.02));
}

.footer-seal i {
  font-style: normal;
  font-family: var(--font-serif);
  font-size: 17px;
  color: var(--gold);
  transform: rotate(-45deg);
}

.footer-logo-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.footer-logo-name {
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--gold);
}

.footer-logo-en {
  font-family: var(--font-mono);
  font-size: 9.5px;
  letter-spacing: 0.3em;
  color: rgba(201, 162, 39, 0.45);
  text-transform: uppercase;
}

.footer-slogan {
  font-family: var(--font-serif);
  font-size: 17px;
  color: var(--light-gold);
  letter-spacing: 0.14em;
  margin-bottom: 12px;
}

.footer-trust {
  max-width: 360px;
  padding-left: 14px;
  border-left: 2px solid rgba(201, 162, 39, 0.4);
  font-size: 13px;
  line-height: 1.8;
  color: rgba(244, 241, 235, 0.55);
}

.footer-heading {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-serif);
  font-size: 16px;
  font-weight: 700;
  color: var(--light-gold);
  letter-spacing: 0.08em;
  margin-bottom: 18px;
}

.footer-heading-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--gold);
  background: rgba(201, 162, 39, 0.12);
  padding: 2px 6px;
  clip-path: polygon(4px 0, 100% 0, calc(100% - 4px) 100%, 0 100%);
}

.footer-links li + li {
  margin-top: 10px;
}

.footer-links a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: rgba(244, 241, 235, 0.62);
  font-size: 14px;
  transition: color 0.3s, transform 0.3s;
}

.footer-links a::before {
  content: "›";
  font-family: var(--font-mono);
  font-size: 14px;
  line-height: 1;
  color: rgba(201, 162, 39, 0.5);
  transition: color 0.3s;
}

.footer-links a:hover {
  color: var(--gold);
  transform: translateX(3px);
}

.footer-links a:hover::before {
  color: var(--gold);
}

.footer-contact-list {
  display: grid;
  gap: 8px;
  font-size: 13px;
  line-height: 1.7;
  color: rgba(244, 241, 235, 0.62);
}

.footer-contact-list li {
  display: flex;
  gap: 8px;
}

.footer-contact-list strong {
  min-width: 38px;
  flex-shrink: 0;
  color: var(--light-gold);
  font-weight: 500;
}

.footer-bottom {
  position: relative;
  z-index: 1;
  background: rgba(4, 12, 28, 0.35);
  border-top: 1px solid rgba(201, 162, 39, 0.18);
  padding-block: 16px;
}

.footer-bottom-inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 24px;
  font-size: 12.5px;
  color: rgba(244, 241, 235, 0.45);
}

.footer-copyright {
  display: flex;
  gap: 6px;
}

.footer-bottom-nav {
  display: flex;
  gap: 16px;
}

.footer-bottom-nav a {
  color: rgba(244, 241, 235, 0.5);
  transition: color 0.3s;
}

.footer-bottom-nav a:hover {
  color: var(--gold);
}

.footer-icp {
  font-family: var(--font-mono);
  letter-spacing: 0.04em;
}

/* ---------- 10. Back to Top ---------- */
.top-btn {
  position: fixed;
  right: 28px;
  bottom: 32px;
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 190;
  background: var(--royal-blue);
  border: 1px solid rgba(201, 162, 39, 0.5);
  color: var(--gold);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity 0.3s, visibility 0.3s, transform 0.3s;
  clip-path: polygon(8px 0, 100% 0, 100% calc(100% - 8px), calc(100% - 8px) 100%, 0 100%, 0 8px);
}

.top-btn.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.top-btn span {
  display: block;
}

.top-btn span::before {
  content: "";
  display: block;
  width: 10px;
  height: 10px;
  border-top: 2px solid currentColor;
  border-right: 2px solid currentColor;
  transform: rotate(-45deg);
}

.top-btn:hover {
  background: var(--steel);
}

/* ---------- 11. Shared Components ---------- */
.gold-text {
  background: linear-gradient(115deg, #9A7B24 0%, #C9A227 25%, #E8D9A0 50%, #C9A227 75%, #8C6D14 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: var(--gold);
  -webkit-text-fill-color: transparent;
}

.chamfer {
  clip-path: polygon(var(--cut) 0, 100% 0, 100% calc(100% - var(--cut)), calc(100% - var(--cut)) 100%, 0 100%, 0 var(--cut));
}

.index-num {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.02em;
  color: var(--gold);
}

.card {
  position: relative;
  background: #fff;
  border: 1px solid rgba(201, 162, 39, 0.22);
  padding: 28px;
  clip-path: polygon(18px 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%, 0 18px);
  transition: transform 0.3s, filter 0.3s;
}

.card:hover {
  transform: translateY(-4px);
  filter: drop-shadow(0 14px 28px rgba(11, 30, 63, 0.16));
}

.figure {
  margin: 0;
}

.figure-caption {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 8px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.04em;
  color: var(--mist);
}

.figure-caption::before {
  content: "";
  width: 22px;
  height: 1px;
  background: var(--gold);
}

.image-frame {
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, var(--steel), var(--royal-blue));
  aspect-ratio: 4 / 3;
  clip-path: polygon(20px 0, 100% 0, 100% calc(100% - 20px), calc(100% - 20px) 100%, 0 100%, 0 20px);
}

.image-frame img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s var(--ease);
}

.image-frame:hover img {
  transform: scale(1.04);
}

.image-frame--wide {
  aspect-ratio: 16 / 9;
}

.image-frame--square {
  aspect-ratio: 1 / 1;
}

.image-frame--portrait {
  aspect-ratio: 3 / 4;
}

.stat {
  padding: 24px;
  background: var(--jade);
  color: rgba(244, 241, 235, 0.85);
  clip-path: polygon(16px 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%, 0 16px);
}

.stat-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 42px;
  font-weight: 700;
  line-height: 1;
  color: var(--gold);
}

.stat-label {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  color: rgba(244, 241, 235, 0.7);
}

.stat--blue {
  background: var(--steel);
}

.stat--crimson {
  background: var(--crimson);
}

.stat--ivory {
  background: var(--ivory);
  border: 1px solid rgba(201, 162, 39, 0.3);
  color: var(--royal-blue);
}

.stat--ivory .stat-label {
  color: var(--steel);
}

/* ---------- 12. Accordion ---------- */
.accordion,
[data-accordion] {
  display: grid;
  gap: 14px;
}

.accordion-item,
[data-accordion-item] {
  background: #fff;
  border: 1px solid rgba(201, 162, 39, 0.25);
  clip-path: polygon(16px 0, 100% 0, 100% calc(100% - 16px), calc(100% - 16px) 100%, 0 100%, 0 16px);
  transition: border-color 0.3s, background-color 0.3s;
}

.accordion-item[data-open],
[data-accordion-item][data-open] {
  border-color: rgba(201, 162, 39, 0.5);
}

.accordion-toggle,
[data-accordion-toggle] {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 18px 22px;
  text-align: left;
  font-size: 15px;
  font-weight: 500;
  color: var(--royal-blue);
  transition: color 0.3s;
}

.accordion-toggle:hover,
[data-accordion-toggle]:hover {
  color: var(--gold);
}

.accordion-index {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--gold);
  flex-shrink: 0;
}

.accordion-icon {
  position: relative;
  margin-left: auto;
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  border: 1px solid rgba(201, 162, 39, 0.5);
  transition: transform 0.3s var(--ease);
}

.accordion-icon::before,
.accordion-icon::after {
  content: "";
  position: absolute;
  background: var(--gold);
  transition: transform 0.3s var(--ease);
}

.accordion-icon::before {
  left: 4px;
  right: 4px;
  top: 50%;
  height: 1px;
  transform: translateY(-50%);
}

.accordion-icon::after {
  top: 4px;
  bottom: 4px;
  left: 50%;
  width: 1px;
  transform: translateX(-50%);
}

.accordion-item[data-open] .accordion-icon,
[data-accordion-item][data-open] .accordion-icon {
  transform: rotate(180deg);
}

.accordion-item[data-open] .accordion-icon::after,
[data-accordion-item][data-open] .accordion-icon::after {
  transform: translateX(-50%) scaleY(0);
}

.accordion-panel,
[data-accordion-panel] {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s var(--ease);
}

.accordion-panel-inner {
  padding: 0 22px 20px 48px;
  color: var(--steel);
  font-size: 14px;
  line-height: 1.8;
}

/* ---------- 13. Responsive ---------- */
@media (max-width: 980px) {
  .header-box {
    min-height: 58px;
  }

  .header-utility-inner {
    min-height: 30px;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .site-nav,
  [data-nav] {
    position: fixed;
    top: 0;
    right: 0;
    height: 100vh;
    height: 100dvh;
    width: min(340px, 86vw);
    padding: 88px 28px 32px;
    overflow-y: auto;
    background: var(--royal-blue);
    border-left: 1px solid rgba(201, 162, 39, 0.3);
    box-shadow: -24px 0 60px rgba(5, 12, 28, 0.5);
    transform: translateX(102%);
    visibility: hidden;
    transition: transform 0.38s var(--ease), visibility 0.38s;
    z-index: 120;
  }

  .site-nav[data-open],
  [data-nav][data-open] {
    transform: translateX(0);
    visibility: visible;
  }

  .nav-drawer-head {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 1px solid rgba(201, 162, 39, 0.18);
  }

  .nav-drawer-title {
    font-family: var(--font-serif);
    font-size: 18px;
    color: var(--gold);
    letter-spacing: 0.08em;
  }

  .nav-drawer-meta {
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.18em;
    color: rgba(201, 162, 39, 0.4);
  }

  .nav-drawer-foot {
    display: block;
    margin-top: 28px;
    padding-top: 16px;
    border-top: 1px solid rgba(201, 162, 39, 0.2);
    font-family: var(--font-mono);
    font-size: 11px;
    line-height: 1.7;
    letter-spacing: 0.04em;
    color: rgba(201, 162, 39, 0.5);
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 8px;
    border-top: 1px solid rgba(201, 162, 39, 0.22);
    padding-top: 18px;
  }

  .nav-link {
    justify-content: space-between;
    padding: 12px 16px;
    font-size: 16px;
    border: 1px solid transparent;
  }

  .nav-link-index {
    order: 2;
    font-size: 12px;
  }

  .nav-link[aria-current="page"] {
    border-color: rgba(201, 162, 39, 0.3);
    background: rgba(201, 162, 39, 0.1);
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 28px;
  }
}

@media (max-width: 640px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .footer-bottom-inner {
    justify-content: center;
    text-align: center;
  }
}

@media (max-width: 560px) {
  .header-utility-note {
    display: none;
  }

  .brand-name {
    font-size: 18px;
  }

  .brand-en {
    display: none;
  }

  .brand-seal {
    width: 36px;
    height: 36px;
  }

  .brand-seal i {
    font-size: 16px;
  }

  .top-btn {
    right: 18px;
    bottom: 22px;
    width: 42px;
    height: 42px;
  }
}

@media (min-width: 641px) {
  .grid--2 {
    grid-template-columns: repeat(2, 1fr);
  }

  .grid--3,
  .grid--4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 981px) {
  .grid--3 {
    grid-template-columns: repeat(3, 1fr);
  }

  .grid--4 {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* ---------- 14. Reveal Motion ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.65s var(--ease), transform 0.65s var(--ease);
  transition-delay: var(--reveal-delay, 0s);
}

[data-reveal].is-revealed {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- 15. Reduced Motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

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

  .site-nav,
  [data-nav] {
    transition: none;
  }
}