/* ==========================================================
   德信体育汇 · shared site.css
   坐标中国 / 展览画册 / 运动计时场
   ========================================================== */

/* ---------- Variables ---------- */
:root {
  --cream: #F7F5EF;
  --deep-blue: #0B1A2A;
  --orange: #FF5C28;
  --neon-green: #C6FF00;
  --steel-blue: #274B6D;
  --warm-gray: #B7C4CF;
  --brown-black: #1E1B1A;
  --light-blue: #DCE7F0;
  --red-orange: #E8432A;

  --font-headline: 'Archivo Black', 'Arial Black', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-body: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  --font-numeric: 'Roboto Mono', 'SF Mono', 'Consolas', 'Courier New', monospace;

  --container-max: 1200px;
  --container-pad: clamp(16px, 4vw, 32px);
  --header-h: 72px;
  --header-h-scrolled: 62px;
  --radius-lg: 24px;
  --radius-md: 14px;
  --radius-pill: 999px;
  --transition-fast: 160ms ease;
  --transition-base: 280ms ease;
}

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

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

body {
  background: var(--cream);
  color: var(--brown-black);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.7;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
}

#main-content {
  flex: 1 0 auto;
  outline: none;
}

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

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

ul, ol {
  list-style: none;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-headline);
  font-weight: 700;
  line-height: 1.2;
  color: inherit;
}

button {
  font-family: inherit;
  cursor: pointer;
}

/* ---------- Utilities ---------- */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.container {
  width: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-pad);
}

/* ---------- Focus ---------- */
:focus-visible {
  outline: 3px solid var(--orange);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---------- Skip Link ---------- */
.skip-link {
  position: fixed;
  top: -120px;
  left: 16px;
  z-index: 1005;
  background: var(--orange);
  color: var(--deep-blue);
  font-family: var(--font-body);
  font-weight: 700;
  font-size: 0.85rem;
  padding: 10px 22px;
  border-radius: var(--radius-pill);
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: 12px;
}

/* ---------- Scroll Progress ---------- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0%;
  background: linear-gradient(90deg, var(--orange) 0%, var(--orange) 72%, var(--neon-green) 100%);
  z-index: 1002;
  pointer-events: none;
  transition: width 80ms linear;
}

/* ---------- Header ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--header-h);
  background: transparent;
  color: var(--cream);
  transition: background-color var(--transition-base), box-shadow var(--transition-base), height var(--transition-base);
}

.site-header[data-scrolled] {
  background: var(--deep-blue);
  box-shadow: 0 4px 24px rgba(11, 26, 42, 0.35);
  height: var(--header-h-scrolled);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  height: 100%;
  max-width: var(--container-max);
  margin-inline: auto;
  padding-inline: var(--container-pad);
}

/* ---------- Brand ---------- */
.site-brand {
  display: inline-flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 2px;
  flex-shrink: 0;
  position: relative;
}

.site-brand__cn {
  font-family: var(--font-headline);
  font-size: 1.35rem;
  font-weight: 900;
  line-height: 1;
  color: var(--orange);
  letter-spacing: -0.01em;
  transition: color var(--transition-base);
}

.site-brand__cn-accent {
  color: var(--cream);
  transition: color var(--transition-base);
}

.site-header[data-scrolled] .site-brand__cn {
  color: var(--cream);
}

.site-header[data-scrolled] .site-brand__cn-accent {
  color: var(--orange);
}

.site-brand__en {
  font-family: var(--font-numeric);
  font-size: 0.58rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: rgba(247, 245, 239, 0.55);
  transition: color var(--transition-base);
}

.site-header[data-scrolled] .site-brand__en {
  color: rgba(255, 92, 40, 0.65);
}

/* ---------- Navigation ---------- */
.site-nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.nav-link {
  display: block;
  padding: 8px 16px;
  border-radius: var(--radius-pill);
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 500;
  color: rgba(247, 245, 239, 0.85);
  letter-spacing: 0.02em;
  white-space: nowrap;
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.nav-link:hover,
.nav-link:focus-visible {
  color: var(--orange);
  background: rgba(255, 92, 40, 0.12);
}

.nav-link[aria-current="page"] {
  color: var(--orange);
  background: rgba(255, 92, 40, 0.16);
  font-weight: 700;
}

/* ---------- Header Actions ---------- */
.site-header__actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
}

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-pill);
  color: var(--cream);
  background: transparent;
  border: 1px solid rgba(247, 245, 239, 0.25);
  transition: color var(--transition-fast), border-color var(--transition-fast), background-color var(--transition-fast);
  position: relative;
}

.icon-btn:hover,
.icon-btn:focus-visible {
  color: var(--orange);
  border-color: var(--orange);
  background: rgba(255, 92, 40, 0.12);
}

.icon-btn[data-tooltip]::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: -34px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--deep-blue);
  color: var(--cream);
  font-family: var(--font-body);
  font-size: 0.65rem;
  font-weight: 500;
  padding: 4px 10px;
  border-radius: 6px;
  white-space: nowrap;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-fast), visibility var(--transition-fast);
  pointer-events: none;
}

.icon-btn[data-tooltip]:hover::after {
  opacity: 1;
  visibility: visible;
}

/* ---------- Nav Toggle ---------- */
.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 10px;
  background: transparent;
  border: none;
  border-radius: var(--radius-pill);
  position: relative;
  z-index: 1001;
}

.nav-toggle__box {
  position: relative;
  width: 24px;
  height: 18px;
  display: block;
}

.nav-toggle__line {
  position: absolute;
  left: 0;
  width: 100%;
  height: 2px;
  border-radius: 2px;
  background: var(--cream);
  transition: transform var(--transition-fast), opacity var(--transition-fast), top var(--transition-fast);
}

.nav-toggle__line--top { top: 0; }
.nav-toggle__line--mid { top: 8px; }
.nav-toggle__line--bot { top: 16px; }

.nav-toggle[aria-expanded="true"] .nav-toggle__line--top {
  top: 8px;
  transform: rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__line--mid {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__line--bot {
  top: 8px;
  transform: rotate(-45deg);
}

/* ---------- Footer ---------- */
.site-footer {
  background: var(--brown-black);
  color: rgba(247, 245, 239, 0.8);
  font-family: var(--font-body);
  padding: 60px 0 0;
  position: relative;
}

.site-footer__main {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 32px 24px;
  padding-bottom: 48px;
}

.site-footer__brand {
  grid-column: span 4;
}

.site-footer__col {
  grid-column: span 2;
}

.site-footer__brand .site-brand__cn {
  color: var(--orange);
}

.site-footer__brand .site-brand__cn-accent {
  color: var(--cream);
}

.site-footer__coords {
  display: flex;
  gap: 8px;
  margin-top: 18px;
  font-family: var(--font-numeric);
  font-size: 0.65rem;
  letter-spacing: 0.15em;
  color: rgba(247, 245, 239, 0.35);
}

.site-footer__slogan {
  margin-top: 10px;
  font-family: var(--font-headline);
  font-size: 0.95rem;
  letter-spacing: 0.04em;
  color: rgba(247, 245, 239, 0.9);
  line-height: 1.4;
}

.site-footer__legend {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  margin-top: 18px;
  font-family: var(--font-numeric);
  font-size: 0.65rem;
  letter-spacing: 0.06em;
  color: rgba(247, 245, 239, 0.5);
}

.legend-marker {
  width: 8px;
  height: 8px;
  border-radius: 2px;
  display: inline-block;
}

.legend-marker--orange {
  background: var(--orange);
}

.legend-marker--green {
  background: var(--neon-green);
  box-shadow: 0 0 8px rgba(198, 255, 0, 0.5);
}

.site-footer__title {
  font-family: var(--font-headline);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--cream);
  margin-bottom: 16px;
  position: relative;
  padding-bottom: 8px;
}

.site-footer__title::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: 0;
  width: 20px;
  height: 2px;
  background: var(--orange);
  border-radius: 2px;
}

.site-footer__list li {
  margin-bottom: 2px;
}

.footer-link {
  display: inline-block;
  font-size: 0.83rem;
  line-height: 2.1;
  color: rgba(247, 245, 239, 0.65);
  transition: color var(--transition-fast), padding-left var(--transition-fast), transform var(--transition-fast);
}

.footer-link:hover,
.footer-link:focus-visible {
  color: var(--orange);
  padding-left: 4px;
}

.site-footer__badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 16px;
  padding: 4px 12px;
  border-radius: var(--radius-pill);
  background: rgba(198, 255, 0, 0.1);
  border: 1px solid rgba(198, 255, 0, 0.3);
}

.site-footer__badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--neon-green);
  animation: pulse-green 2s ease-in-out infinite;
}

.site-footer__badge-text {
  font-family: var(--font-numeric);
  font-size: 0.55rem;
  letter-spacing: 0.14em;
  color: var(--neon-green);
}

@keyframes pulse-green {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.45; transform: scale(0.75); }
}

.site-footer__contact {
  border-top: 1px solid rgba(247, 245, 239, 0.08);
  background: rgba(0, 0, 0, 0.18);
  padding: 18px 0;
}

.site-footer__contact-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  align-items: center;
  justify-content: center;
}

.footer-chip {
  display: inline-flex;
  align-items: center;
  padding: 5px 14px;
  border: 1px solid rgba(247, 245, 239, 0.16);
  border-radius: var(--radius-pill);
  font-family: var(--font-numeric);
  font-size: 0.68rem;
  letter-spacing: 0.02em;
  color: rgba(247, 245, 239, 0.65);
  background: rgba(247, 245, 239, 0.03);
}

.site-footer__bottom {
  padding: 16px 0 20px;
}

.site-footer__bottom-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 24px;
  align-items: center;
  justify-content: space-between;
  font-family: var(--font-numeric);
  font-size: 0.68rem;
  color: rgba(247, 245, 239, 0.4);
}

.site-footer__trust {
  flex-basis: 100%;
  text-align: center;
  font-family: var(--font-body);
  font-size: 0.72rem;
  line-height: 1.6;
  color: rgba(247, 245, 239, 0.32);
  margin-top: 6px;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: var(--radius-pill);
  border: 2px solid transparent;
  font-family: var(--font-headline);
  font-size: 0.85rem;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: 0.02em;
  text-decoration: none;
  text-align: center;
  white-space: nowrap;
  user-select: none;
  transition: background-color var(--transition-fast), color var(--transition-fast), border-color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
}

.btn:hover {
  transform: translateY(-2px);
}

.btn:active {
  transform: translateY(0);
}

.btn--primary {
  background: var(--orange);
  border-color: var(--orange);
  color: var(--deep-blue);
}

.btn--primary:hover {
  background: #FF7350;
  border-color: #FF7350;
  box-shadow: 0 8px 24px rgba(255, 92, 40, 0.35);
}

.btn--dark {
  background: var(--deep-blue);
  border-color: var(--deep-blue);
  color: var(--cream);
}

.btn--dark:hover {
  background: var(--steel-blue);
  border-color: var(--steel-blue);
  box-shadow: 0 8px 20px rgba(39, 75, 109, 0.35);
}

.btn--ghost {
  background: transparent;
  border-color: rgba(247, 245, 239, 0.45);
  color: var(--cream);
}

.btn--ghost:hover {
  border-color: var(--orange);
  color: var(--orange);
}

.btn--accent {
  background: var(--neon-green);
  border-color: var(--neon-green);
  color: var(--deep-blue);
}

.btn--accent:hover {
  background: #D4FF33;
  border-color: #D4FF33;
  box-shadow: 0 8px 20px rgba(198, 255, 0, 0.3);
}

.btn--sm {
  padding: 8px 18px;
  font-size: 0.75rem;
}

.btn--lg {
  padding: 16px 36px;
  font-size: 1rem;
}

.btn-group {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}

/* ---------- Typography Components ---------- */
.chapter-num {
  font-family: var(--font-numeric);
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  line-height: 1;
  color: var(--orange);
  letter-spacing: -0.04em;
}

.section-heading {
  display: flex;
  align-items: baseline;
  gap: 16px;
  margin-bottom: 36px;
}

.section-title {
  font-family: var(--font-headline);
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  line-height: 1.15;
  color: var(--deep-blue);
  letter-spacing: -0.01em;
}

.section-heading--dark .section-title {
  color: var(--cream);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-numeric);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--steel-blue);
}

.eyebrow::before {
  content: '';
  width: 16px;
  height: 2px;
  background: var(--orange);
  border-radius: 2px;
}

.stat-num {
  font-family: var(--font-numeric);
  font-size: clamp(2rem, 4vw, 3.5rem);
  font-weight: 700;
  line-height: 1;
  color: var(--deep-blue);
  letter-spacing: -0.02em;
  display: block;
}

.stat-label {
  display: block;
  margin-top: 8px;
  font-family: var(--font-body);
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--steel-blue);
}

.stat-label::before {
  content: '· ';
  color: var(--orange);
}

/* ---------- Grid Layouts ---------- */
.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: clamp(16px, 3vw, 32px);
}

.grid-asym {
  display: grid;
  grid-template-columns: 8fr 4fr;
  gap: clamp(16px, 3vw, 40px);
  align-items: start;
}

.grid-split {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: clamp(16px, 3vw, 32px);
}

/* ---------- Cards ---------- */
.card {
  background: var(--cream);
  border-radius: var(--radius-lg);
  padding: 28px;
  position: relative;
  border: 1px solid rgba(183, 196, 207, 0.35);
  transition: transform var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 14px 36px rgba(11, 26, 42, 0.1);
  border-color: rgba(255, 92, 40, 0.3);
}

.card--dark {
  background: var(--deep-blue);
  color: var(--cream);
  border-color: transparent;
}

.card--dark:hover {
  box-shadow: 0 14px 36px rgba(11, 26, 42, 0.35);
  border-color: rgba(255, 92, 40, 0.2);
}

.card--skew {
  clip-path: polygon(0 0, calc(100% - 24px) 0, 100% 24px, 100% 100%, 24px 100%, 0 calc(100% - 24px));
}

.card__title {
  font-family: var(--font-headline);
  font-size: 1.15rem;
  line-height: 1.25;
  margin-bottom: 10px;
  color: var(--deep-blue);
}

.card--dark .card__title {
  color: var(--cream);
}

.card__text {
  font-size: 0.88rem;
  line-height: 1.65;
  color: rgba(27, 27, 26, 0.75);
}

.card--dark .card__text {
  color: rgba(247, 245, 239, 0.7);
}

/* ---------- Media Frames ---------- */
.media-frame {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, var(--light-blue) 0%, var(--steel-blue) 100%);
  aspect-ratio: 16 / 9;
  display: flex;
  align-items: center;
  justify-content: center;
}

.media-frame--dark {
  background: linear-gradient(135deg, var(--deep-blue) 0%, var(--steel-blue) 100%);
}

.media-frame--orange {
  background: linear-gradient(135deg, var(--orange) 0%, var(--red-orange) 100%);
}

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

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

.media-frame--video {
  aspect-ratio: 4 / 5;
}

.media-frame__placeholder {
  font-family: var(--font-numeric);
  font-size: 0.72rem;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--steel-blue);
  position: relative;
  z-index: 1;
}

.media-frame--dark .media-frame__placeholder {
  color: rgba(247, 245, 239, 0.4);
}

.media-frame--orange .media-frame__placeholder {
  color: var(--cream);
}

.media-frame::after {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 32%;
  height: 100%;
  background: linear-gradient(135deg, transparent 0%, transparent 48%, rgba(255, 92, 40, 0.22) 50%, rgba(255, 92, 40, 0.28) 100%);
  pointer-events: none;
}

/* ---------- Data Components ---------- */
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-numeric);
  font-size: 0.83rem;
  background: var(--cream);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.data-table thead th {
  background: var(--deep-blue);
  color: var(--cream);
  padding: 12px 16px;
  font-weight: 600;
  text-align: left;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-size: 0.68rem;
  white-space: nowrap;
}

.data-table thead th:first-child {
  border-radius: var(--radius-md) 0 0 0;
}

.data-table thead th:last-child {
  border-radius: 0 var(--radius-md) 0 0;
}

.data-table tbody td {
  padding: 12px 16px;
  border-bottom: 1px solid rgba(183, 196, 207, 0.4);
  color: var(--brown-black);
}

.data-table tbody tr:last-child td {
  border-bottom: none;
}

.data-table tbody tr:hover td {
  background: var(--light-blue);
}

.data-table .data-highlight {
  color: var(--orange);
  font-weight: 700;
}

.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.filter-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 20px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--warm-gray);
  background: transparent;
  font-family: var(--font-body);
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--steel-blue);
  transition: border-color var(--transition-fast), color var(--transition-fast), background-color var(--transition-fast), box-shadow var(--transition-fast);
}

.filter-btn:hover {
  border-color: var(--orange);
  color: var(--orange);
}

.filter-btn[data-active] {
  background: var(--neon-green);
  border-color: var(--neon-green);
  color: var(--deep-blue);
  font-weight: 700;
  box-shadow: 0 2px 12px rgba(198, 255, 0, 0.35);
}

.copy-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 16px;
  border-radius: var(--radius-pill);
  background: var(--light-blue);
  border: 1px solid transparent;
  font-family: var(--font-numeric);
  font-size: 0.68rem;
  color: var(--steel-blue);
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.copy-btn:hover {
  background: var(--deep-blue);
  color: var(--neon-green);
}

/* ---------- Breadcrumb ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  align-items: center;
  font-family: var(--font-numeric);
  font-size: 0.75rem;
  color: var(--warm-gray);
}

.breadcrumb__item {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.breadcrumb__item:not(:last-child)::after {
  content: '/';
  color: var(--warm-gray);
  opacity: 0.55;
  font-size: 0.7rem;
}

.breadcrumb__link {
  color: var(--steel-blue);
  transition: color var(--transition-fast);
}

.breadcrumb__link:hover {
  color: var(--orange);
}

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

/* ---------- Content Prose ---------- */
.content-prose {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.8;
  color: var(--brown-black);
  max-width: 720px;
}

.content-prose h2 {
  font-family: var(--font-headline);
  font-size: 1.5rem;
  line-height: 1.3;
  color: var(--deep-blue);
  margin-top: 2.5em;
  margin-bottom: 0.75em;
}

.content-prose h3 {
  font-family: var(--font-headline);
  font-size: 1.15rem;
  line-height: 1.3;
  color: var(--deep-blue);
  margin-top: 1.8em;
  margin-bottom: 0.5em;
}

.content-prose p {
  margin-bottom: 1.2em;
}

.content-prose a {
  color: var(--steel-blue);
  text-decoration: underline;
  text-underline-offset: 4px;
  transition: color var(--transition-fast);
}

.content-prose a:hover {
  color: var(--orange);
}

.content-prose ul {
  list-style: none;
  margin-bottom: 1.2em;
  padding-left: 0;
}

.content-prose ul li {
  position: relative;
  padding-left: 20px;
  margin-bottom: 6px;
}

.content-prose ul li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.7em;
  width: 8px;
  height: 8px;
  border-radius: 2px;
  background: var(--orange);
}

/* ---------- Back Top ---------- */
.back-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 48px;
  height: 48px;
  border-radius: var(--radius-pill);
  background: var(--orange);
  color: var(--deep-blue);
  border: none;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px);
  transition: opacity var(--transition-base), transform var(--transition-base), visibility var(--transition-base), background-color var(--transition-fast);
  z-index: 999;
  box-shadow: 0 8px 24px rgba(255, 92, 40, 0.4);
}

.back-top[data-visible] {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-top:hover {
  background: #FF7350;
  transform: translateY(-2px);
}

/* ---------- Scroll Reveal ---------- */
@media (prefers-reduced-motion: no-preference) {
  [data-reveal] {
    opacity: 0;
    transform: translateX(24px);
    transition: opacity 600ms ease, transform 600ms ease;
  }

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

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
  .site-footer__brand {
    grid-column: span 6;
  }

  .site-footer__col {
    grid-column: span 3;
  }

  .grid-asym {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 960px) {
  .site-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    background: var(--deep-blue);
    padding: 16px;
    border-bottom: 2px solid var(--orange);
    max-height: calc(100dvh - var(--header-h));
    overflow-y: auto;
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transform: translateY(-12px);
    transition: opacity var(--transition-base), transform var(--transition-base), visibility var(--transition-base);
  }

  .site-nav[data-open] {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: translateY(0);
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
  }

  .nav-link {
    padding: 14px 20px;
    font-size: 1rem;
    border-radius: var(--radius-md);
  }

  .nav-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }
}

@media (max-width: 768px) {
  .site-footer__brand {
    grid-column: span 12;
  }

  .site-footer__col {
    grid-column: span 6;
  }
}

@media (max-width: 640px) {
  :root {
    --header-h: 60px;
    --header-h-scrolled: 54px;
  }

  .site-brand__cn {
    font-size: 1.1rem;
  }

  .site-brand__en {
    font-size: 0.5rem;
  }

  .icon-btn {
    width: 36px;
    height: 36px;
  }

  .icon-btn svg {
    width: 16px;
    height: 16px;
  }

  .site-footer {
    padding-top: 40px;
  }

  .site-footer__main {
    gap: 24px;
    padding-bottom: 36px;
  }

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

  .site-footer__bottom-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
  }

  .site-footer__trust {
    text-align: left;
  }

  .grid-split {
    grid-template-columns: 1fr;
  }

  .grid-12 {
    grid-template-columns: repeat(6, 1fr);
  }

  .btn--lg {
    padding: 14px 28px;
    font-size: 0.9rem;
  }

  .back-top {
    bottom: 20px;
    right: 20px;
    width: 44px;
    height: 44px;
  }
}

@media (max-width: 480px) {
  .icon-btn[data-tooltip]::after {
    display: none;
  }
}

/* ---------- 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;
  }

  .back-top {
    transition: none;
  }

  .scroll-progress {
    transition: none;
  }
}