/* ================================================================
   浩瀚体育 — SITE.CSS 共享样式
   文件位置: /assets/site.css
   ================================================================ */

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", "Helvetica Neue", Arial, sans-serif;
  font-size: 1rem;
  line-height: 1.6;
  color: #E5E9F0;
  background-color: #0A1931;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

ul, ol {
  list-style: none;
}

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

h1, h2, h3, h4 {
  font-weight: 900;
  line-height: 1.2;
  color: inherit;
}

::selection {
  background: rgba(255, 107, 0, 0.25);
  color: inherit;
}

:focus-visible {
  outline: 2px solid #F4B400;
  outline-offset: 2px;
  border-radius: 2px;
}

/* ---------- 2. CSS Variables ---------- */
:root {
  --c-navy: #0A1931;
  --c-orange: #FF6B00;
  --c-gold: #F4B400;
  --c-red: #E44D2E;
  --c-deep: #0F1A2E;
  --c-light: #F5F7FA;
  --c-ink: #1C1E26;
  --c-text-light: #E5E9F0;
  --c-data: #00B4D8;
  --c-border: #2A3B52;

  --font-heading: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-body: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
  --font-data: "SF Mono", "Roboto Mono", Consolas, "Liberation Mono", monospace;

  --header-h: 64px;
  --header-total: calc(var(--header-h) + 1px);
  --content-max: 1200px;
  --content-pad: 24px;
  --radius-sm: 4px;
  --radius-md: 8px;
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
}

/* ---------- 3. Scrollbar ---------- */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

::-webkit-scrollbar-track {
  background: #0A1931;
}

::-webkit-scrollbar-thumb {
  background: #2A3B52;
  border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
  background: #FF6B00;
}

/* ---------- 4. Layout Utilities ---------- */
#main-content {
  display: block;
  padding-top: var(--header-total);
  min-height: 60vh;
}

.container {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 var(--content-pad);
}

.container--narrow {
  max-width: 800px;
}

.section {
  padding: 72px 0;
}

.section--light {
  background-color: var(--c-light);
  color: var(--c-ink);
}

.section--dark {
  background-color: var(--c-navy);
  color: var(--c-text-light);
}

.section-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 40px;
  position: relative;
}

.section-header__index {
  display: block;
  font-family: var(--font-data);
  font-size: 14px;
  font-weight: 700;
  color: var(--c-orange);
  letter-spacing: 0.08em;
  margin-bottom: 4px;
}

.section-header__index::before {
  content: "/";
  margin-right: 4px;
}

.section-header__title {
  font-size: 32px;
  font-weight: 900;
  line-height: 1.15;
  letter-spacing: 0.02em;
  color: inherit;
}

.section-header__note {
  font-size: 14px;
  color: inherit;
  opacity: 0.6;
  max-width: 360px;
  text-align: right;
  line-height: 1.5;
  flex-shrink: 0;
}

@media (max-width: 768px) {
  .section-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

  .section-header__note {
    text-align: left;
    max-width: none;
  }

  .section-header__title {
    font-size: 26px;
  }
}

/* ---------- 5. Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 12px 20px;
  font-size: 14px;
  font-weight: 600;
  line-height: 1.2;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.2s var(--ease-out);
  white-space: nowrap;
  position: relative;
}

.btn--primary {
  background-color: var(--c-orange);
  color: #0A1931;
  border-color: var(--c-orange);
  clip-path: polygon(10px 0, 100% 0, 100% calc(100% - 10px), calc(100% - 10px) 100%, 0 100%, 0 10px);
}

.btn--primary:hover {
  background-color: #ff7d1f;
  border-color: #ff7d1f;
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(255, 107, 0, 0.3);
}

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

.btn--ghost {
  background: rgba(255, 255, 255, 0.03);
  color: var(--c-text-light);
  border-color: var(--c-border);
}

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

.btn--sm {
  padding: 8px 16px;
  font-size: 13px;
}

/* ---------- 6. Skip Link ---------- */
.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 2000;
  background: var(--c-orange);
  color: #0A1931;
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 700;
  transform: translateY(-200%);
  transition: transform 0.2s var(--ease-out);
}

.skip-link:focus {
  transform: translateY(0);
}

/* ---------- 7. Header ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(10, 25, 49, 0.97);
  border-bottom: 1px solid var(--c-border);
  transition: background-color 0.3s, box-shadow 0.3s;
}

.site-header.is-scrolled {
  background: rgba(10, 25, 49, 0.985);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.35);
}

.site-header__inner {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  max-width: 1400px;
  height: var(--header-h);
  margin: 0 auto;
  padding: 0 var(--content-pad);
}

.scroll-progress {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--c-orange), var(--c-gold), var(--c-red));
  transform: scaleX(0);
  transform-origin: 0 50%;
  z-index: 2;
  pointer-events: none;
}

.site-header__stripe {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 2px;
  display: flex;
  z-index: 1;
}

.site-header__stripe-orange,
.site-header__stripe-gold,
.site-header__stripe-red {
  height: 100%;
  flex: 1;
}

.site-header__stripe-orange {
  background: var(--c-orange);
}

.site-header__stripe-gold {
  background: var(--c-gold);
}

.site-header__stripe-red {
  background: var(--c-red);
}

/* ---------- 8. Brand ---------- */
.site-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
  text-decoration: none;
}

.site-brand__mark {
  width: 32px;
  height: 32px;
  filter: drop-shadow(0 0 6px rgba(255, 107, 0, 0.35));
  transition: filter 0.2s;
}

.site-brand:hover .site-brand__mark {
  filter: drop-shadow(0 0 12px rgba(255, 107, 0, 0.6));
}

.site-brand__name {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}

.site-brand__name strong {
  font-size: 18px;
  font-weight: 900;
  color: var(--c-text-light);
  letter-spacing: 0.08em;
}

.site-brand__name em {
  font-family: var(--font-data);
  font-style: normal;
  font-size: 9px;
  letter-spacing: 0.2em;
  color: var(--c-gold);
  text-transform: uppercase;
  margin-top: 3px;
}

.site-brand--footer .site-brand__mark {
  width: 40px;
  height: 40px;
}

.site-brand--footer .site-brand__name strong {
  font-size: 20px;
}

.site-brand--footer .site-brand__name em {
  font-size: 10px;
}

/* ---------- 9. Navigation ---------- */
.site-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  flex: 1;
  gap: 16px;
}

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

.site-nav__item {
  position: relative;
}

.site-nav__link {
  display: flex;
  align-items: baseline;
  gap: 5px;
  padding: 12px 12px;
  color: var(--c-text-light);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.02em;
  border-bottom: 2px solid transparent;
  border-radius: 2px 2px 0 0;
  transition: color 0.2s, background-color 0.2s, border-color 0.2s;
}

.site-nav__link:hover {
  color: var(--c-orange);
  background: rgba(255, 107, 0, 0.05);
  border-bottom-color: var(--c-orange);
}

.site-nav__index {
  font-family: var(--font-data);
  font-size: 11px;
  font-weight: 600;
  color: var(--c-gold);
  opacity: 0.65;
  transition: opacity 0.2s, color 0.2s;
}

.site-nav__link:hover .site-nav__index {
  opacity: 1;
}

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

.site-nav__link[aria-current="page"]::before {
  content: "";
  position: absolute;
  left: 50%;
  top: -2px;
  transform: translateX(-50%);
  border-left: 5px solid transparent;
  border-right: 5px solid transparent;
  border-top: 4px solid var(--c-orange);
}

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

.site-nav__actions {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-left: auto;
  flex-shrink: 0;
}

/* ---------- 10. Nav Toggle ---------- */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border: 1px solid var(--c-border);
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.03);
  color: var(--c-text-light);
  transition: border-color 0.2s, color 0.2s;
}

.nav-toggle:hover {
  border-color: var(--c-gold);
  color: var(--c-gold);
}

.nav-toggle__box {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  width: 18px;
  height: 14px;
}

.nav-toggle__bar {
  width: 100%;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
  transition: transform 0.25s var(--ease-out), opacity 0.2s;
}

.nav-toggle__label {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.06em;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* ---------- 11. Footer ---------- */
.site-footer {
  background-color: var(--c-deep);
  color: var(--c-text-light);
  position: relative;
  border-top: 1px solid var(--c-border);
  overflow: hidden;
}

.site-footer__decor {
  position: relative;
  height: 60px;
  pointer-events: none;
}

.site-footer__shield {
  position: absolute;
  top: 10px;
  left: 50%;
  transform: translateX(-50%);
  width: 220px;
  height: 100px;
  opacity: 0.25;
}

.site-footer__watermark {
  position: absolute;
  right: -10px;
  bottom: -40px;
  font-size: 160px;
  font-weight: 900;
  color: transparent;
  -webkit-text-stroke: 1px rgba(42, 59, 82, 0.5);
  opacity: 0.3;
  line-height: 1;
  -webkit-user-select: none;
  user-select: none;
  letter-spacing: 0.05em;
  pointer-events: none;
}

.site-footer__inner {
  position: relative;
  z-index: 1;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 48px var(--content-pad) 40px;
  display: grid;
  grid-template-columns: 2fr 1fr 1.5fr;
  gap: 48px;
}

.site-footer__col--brand {
  display: flex;
  flex-direction: column;
  max-width: 400px;
}

.site-footer__desc {
  margin-top: 16px;
  font-size: 14px;
  line-height: 1.6;
  color: rgba(229, 233, 240, 0.65);
  max-width: 340px;
}

.site-footer__trust {
  margin-top: 16px;
  padding: 12px 16px;
  font-size: 13px;
  line-height: 1.6;
  color: rgba(229, 233, 240, 0.8);
  border: 1px dashed rgba(244, 180, 0, 0.4);
  border-radius: var(--radius-sm);
  background: rgba(244, 180, 0, 0.03);
  position: relative;
}

.site-footer__trust::before {
  content: "◆";
  position: absolute;
  top: -8px;
  left: 12px;
  color: var(--c-gold);
  background: var(--c-deep);
  padding: 0 4px;
  font-size: 10px;
}

.site-footer__heading {
  font-size: 16px;
  font-weight: 700;
  color: var(--c-text-light);
  letter-spacing: 0.06em;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--c-border);
  position: relative;
}

.site-footer__heading::after {
  content: "";
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 28px;
  height: 2px;
  background: var(--c-orange);
}

.site-footer__col--links {
  padding-left: 4px;
}

.site-footer__links {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 4px 16px;
}

.site-footer__links a {
  display: inline-block;
  padding: 4px 0;
  color: rgba(229, 233, 240, 0.78);
  font-size: 14px;
  transition: color 0.2s, padding-left 0.2s;
}

.site-footer__links a:hover {
  color: var(--c-orange);
  padding-left: 4px;
}

.site-footer__col--contact {
  padding-left: 4px;
}

.site-footer__contact {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  font-size: 14px;
}

.contact-item__label {
  flex-shrink: 0;
  display: inline-block;
  min-width: 32px;
  color: var(--c-gold);
  font-family: var(--font-data);
  font-size: 12px;
  font-weight: 600;
  padding-top: 2px;
}

.site-footer__address {
  color: rgba(229, 233, 240, 0.8);
  line-height: 1.5;
  word-break: break-all;
}

.site-footer__note {
  margin-top: 16px;
  font-size: 13px;
  color: rgba(229, 233, 240, 0.5);
  line-height: 1.6;
  padding: 12px 14px;
  border-left: 2px solid var(--c-orange);
  background: rgba(255, 107, 0, 0.04);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.site-footer__bottom {
  border-top: 1px solid var(--c-border);
  background: rgba(0, 0, 0, 0.2);
}

.site-footer__bottom-inner {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 16px var(--content-pad);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  font-size: 13px;
  color: rgba(229, 233, 240, 0.5);
}

.site-footer__icp {
  letter-spacing: 0.02em;
  font-family: var(--font-data);
}

/* ---------- 12. Back to Top ---------- */
.back-to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 900;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--c-orange), var(--c-red));
  color: #0A1931;
  border: 2px solid rgba(255, 255, 255, 0.2);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 0.25s, transform 0.25s var(--ease-out), visibility 0.25s;
}

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

.back-to-top:hover {
  transform: translateY(-3px);
  box-shadow: 0 6px 24px rgba(255, 107, 0, 0.45);
}

.back-to-top svg {
  width: 18px;
  height: 18px;
}

/* ---------- 13. Cards ---------- */
.card {
  background: #FFFFFF;
  border-radius: var(--radius-md);
  border: 1px solid rgba(42, 59, 82, 0.12);
  box-shadow: 0 2px 4px rgba(10, 25, 49, 0.04), 0 8px 24px rgba(10, 25, 49, 0.08);
  padding: 24px;
  transition: box-shadow 0.25s, transform 0.25s;
}

.card:hover {
  box-shadow: 0 4px 8px rgba(10, 25, 49, 0.06), 0 16px 36px rgba(10, 25, 49, 0.12);
  transform: translateY(-2px);
}

.card--dark {
  background: var(--c-deep);
  color: var(--c-text-light);
  border-color: var(--c-border);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
}

.card--dark:hover {
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.35);
}

/* ---------- 14. Data Elements ---------- */
.data-num {
  font-family: var(--font-data);
  font-variant-numeric: tabular-nums;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.data-label {
  display: inline-block;
  font-size: 12px;
  font-family: var(--font-data);
  letter-spacing: 0.08em;
  color: inherit;
  opacity: 0.5;
  text-transform: uppercase;
}

.data-badge {
  display: inline-flex;
  align-items: center;
  padding: 2px 8px;
  border-radius: 2px;
  font-family: var(--font-data);
  font-size: 12px;
  font-weight: 700;
  line-height: 1.4;
}

.data-badge--orange {
  background: rgba(255, 107, 0, 0.15);
  color: var(--c-orange);
}

.data-badge--gold {
  background: rgba(244, 180, 0, 0.15);
  color: var(--c-gold);
}

.data-badge--red {
  background: rgba(228, 77, 46, 0.15);
  color: var(--c-red);
}

.data-badge--cyan {
  background: rgba(0, 180, 216, 0.15);
  color: var(--c-data);
}

/* ---------- 15. Breadcrumb ---------- */
.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
  font-size: 13px;
  color: inherit;
  opacity: 0.55;
  margin-bottom: 16px;
}

.breadcrumb a {
  color: inherit;
  transition: color 0.2s;
}

.breadcrumb a:hover {
  color: var(--c-orange);
  opacity: 1;
}

.breadcrumb__sep {
  color: inherit;
  opacity: 0.35;
}

/* ---------- 16. Page Hero ---------- */
.page-hero {
  position: relative;
  padding: 48px 0 40px;
  background: var(--c-navy);
  color: var(--c-text-light);
  overflow: hidden;
}

.page-hero::before {
  content: "";
  position: absolute;
  top: -40px;
  right: -40px;
  width: 250px;
  height: 250px;
  border-radius: 50%;
  background: radial-gradient(circle at center, rgba(255, 107, 0, 0.14), transparent 70%);
  pointer-events: none;
}

.page-hero::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--c-orange), var(--c-gold), transparent);
  opacity: 0.6;
}

.page-hero__index {
  font-family: var(--font-data);
  font-size: 14px;
  color: var(--c-orange);
  letter-spacing: 0.1em;
  margin-bottom: 8px;
}

.page-hero__title {
  font-size: 40px;
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: 0.03em;
  color: var(--c-text-light);
}

.page-hero__subtitle {
  margin-top: 8px;
  font-size: 16px;
  color: rgba(229, 233, 240, 0.55);
  max-width: 480px;
}

@media (max-width: 768px) {
  .page-hero {
    padding: 32px 0 32px;
  }

  .page-hero__title {
    font-size: 30px;
  }

  .page-hero__subtitle {
    font-size: 14px;
  }
}

/* ---------- 17. Image Frame ---------- */
.img-frame {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-sm);
  background:
    radial-gradient(ellipse at 70% 20%, rgba(255, 107, 0, 0.22), transparent 50%),
    radial-gradient(ellipse at 15% 85%, rgba(244, 180, 0, 0.12), transparent 40%),
    linear-gradient(135deg, #0F1A2E, #1C2A45);
  aspect-ratio: 16 / 9;
}

.img-frame::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
  background-size: 24px 24px;
  z-index: 0;
}

.img-frame > * {
  position: relative;
  z-index: 1;
}

.img-frame--tall {
  aspect-ratio: 4 / 5;
}

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

.img-frame__badge {
  position: absolute;
  bottom: 12px;
  left: 0;
  z-index: 2;
  background: var(--c-orange);
  color: #0A1931;
  font-family: var(--font-data);
  font-size: 12px;
  font-weight: 700;
  padding: 4px 14px;
  letter-spacing: 0.05em;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

/* ---------- 18. Decorative Backgrounds ---------- */
.has-grid-bg {
  background-image:
    linear-gradient(rgba(42, 59, 82, 0.14) 1px, transparent 1px),
    linear-gradient(90deg, rgba(42, 59, 82, 0.14) 1px, transparent 1px);
  background-size: 32px 32px;
}

.speed-lines {
  background-image: repeating-linear-gradient(
    -45deg,
    transparent,
    transparent 10px,
    rgba(255, 107, 0, 0.05) 10px,
    rgba(255, 107, 0, 0.05) 11px
  );
}

/* ---------- 19. Content Body ---------- */
.content-body {
  font-size: 16px;
  line-height: 1.7;
}

.content-body p {
  margin-bottom: 1em;
}

.content-body h2 {
  font-size: 24px;
  font-weight: 900;
  margin: 1.8em 0 0.8em;
}

.content-body h3 {
  font-size: 20px;
  font-weight: 900;
  margin: 1.5em 0 0.6em;
}

.content-body a {
  color: var(--c-orange);
  text-decoration: underline;
  text-underline-offset: 3px;
}

.content-body ul,
.content-body ol {
  margin-bottom: 1em;
  padding-left: 1.5em;
}

.content-body ul {
  list-style: disc;
}

.content-body ol {
  list-style: decimal;
}

/* ---------- 20. Responsive ---------- */
@media (min-width: 1201px) {
  :root {
    --content-pad: 32px;
  }
}

@media (min-width: 993px) {
  .nav-toggle {
    display: none;
  }
}

@media (max-width: 992px) {
  .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    gap: 0;
    padding: 20px var(--content-pad) 32px;
    background: rgba(10, 25, 49, 0.985);
    border-bottom: 1px solid var(--c-border);
    box-shadow: 0 24px 48px rgba(0, 0, 0, 0.4);
    transform: translateY(-8px);
    opacity: 0;
    visibility: hidden;
    max-height: calc(100vh - var(--header-h));
    overflow-y: auto;
    transition: opacity 0.25s ease, transform 0.25s var(--ease-out), visibility 0.25s;
    flex: none;
  }

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

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    width: 100%;
  }

  .site-nav__item {
    border-bottom: 1px solid rgba(42, 59, 82, 0.4);
  }

  .site-nav__link {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 12px;
    font-size: 16px;
    border-bottom: none;
    border-left: 2px solid transparent;
    border-radius: 0;
  }

  .site-nav__link:hover {
    border-left-color: var(--c-orange);
    background: rgba(255, 107, 0, 0.04);
  }

  .site-nav__link[aria-current="page"] {
    border-left-color: var(--c-orange);
    background: rgba(255, 107, 0, 0.04);
  }

  .site-nav__link[aria-current="page"]::before {
    display: none;
  }

  .site-nav__actions {
    margin-top: 16px;
    display: flex;
    width: 100%;
    gap: 12px;
    margin-left: 0;
  }

  .site-nav__actions .btn {
    flex: 1;
  }

  .site-footer__inner {
    grid-template-columns: 1fr;
    gap: 36px;
    padding: 40px var(--content-pad) 32px;
  }

  .site-footer__col--brand {
    max-width: none;
  }

  .back-to-top {
    right: 16px;
    bottom: 16px;
  }
}

@media (max-width: 640px) {
  :root {
    --content-pad: 16px;
  }

  .site-header__inner {
    gap: 8px;
  }

  .site-brand__mark {
    width: 28px;
    height: 28px;
  }

  .site-brand__name strong {
    font-size: 16px;
  }

  .site-brand__name em {
    font-size: 8px;
    letter-spacing: 0.12em;
  }

  .nav-toggle__label {
    display: none;
  }

  .section {
    padding: 48px 0;
  }

  .site-footer__links {
    grid-template-columns: 1fr 1fr;
  }

  .site-footer__bottom-inner {
    flex-direction: column;
    gap: 4px;
    padding: 14px var(--content-pad);
  }
}

/* ---------- 21. Accessibility ---------- */
@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;
  }

  .skip-link {
    transition: none;
  }

  .site-nav,
  .nav-toggle__bar,
  .back-to-top,
  .card,
  .btn {
    transition: none;
  }
}