/* ======================================
   米兰体育 · 全站共享样式 /assets/site.css
   ====================================== */

/* ---------- 1. Design Tokens ---------- */
:root {
  --ms-red: #D40000;
  --ms-midnight: #1A1A2E;
  --ms-gold: #FFD700;
  --ms-gray: #F5F5F5;
  --ms-dark: #0D0D1A;
  --ms-text: #1A1A2E;
  --ms-white: #FFFFFF;
  --ms-muted: #6B7280;

  --font-head: 'Oswald', 'PingFang SC', 'Microsoft YaHei', 'Heiti SC', sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-mono: 'JetBrains Mono', 'SF Mono', Consolas, monospace;

  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-pill: 999px;

  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 40px;
  --space-5: 64px;
  --space-6: 80px;

  --content-max: 1440px;

  --shadow-card: 0 2px 12px rgba(0, 0, 0, 0.06);
  --shadow-float: 0 8px 24px rgba(0, 0, 0, 0.12);
  --shadow-red: 0 4px 16px rgba(212, 0, 0, 0.3);

  --transition-fast: 150ms;
  --transition-base: 200ms;
  --transition-slow: 300ms;
}

/* ---------- 2. Reset & Base ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

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

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--ms-text);
  background: var(--ms-gray);
  overflow-x: hidden;
}

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

h1,
h2,
h3,
h4 {
  font-family: var(--font-head);
  font-weight: 700;
  line-height: 1.2;
  margin: 0 0 16px;
}

h1 {
  font-size: clamp(2rem, 4vw, 3.5rem);
}

h2 {
  font-size: clamp(1.5rem, 3vw, 2.5rem);
}

h3 {
  font-size: clamp(1.25rem, 2vw, 1.75rem);
}

p {
  margin: 0 0 16px;
}

ul,
ol {
  margin: 0 0 16px;
  padding-left: 24px;
}

a {
  color: var(--ms-red);
  text-decoration: underline;
  text-underline-offset: 3px;
}

a:hover {
  color: #a30000;
}

button {
  font-family: inherit;
}

::selection {
  background: var(--ms-red);
  color: var(--ms-white);
}

:focus-visible {
  outline: 2px solid var(--ms-gold);
  outline-offset: 2px;
  box-shadow: 0 0 0 4px rgba(255, 215, 0, 0.25);
  border-radius: 4px;
}

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

/* ---------- 3. Skip Link ---------- */
.skip-link {
  position: absolute;
  top: -56px;
  left: 16px;
  z-index: 300;
  padding: 12px 24px;
  background: var(--ms-gold);
  color: var(--ms-dark);
  border-radius: var(--radius-pill);
  font-weight: 600;
  font-size: 0.9rem;
  text-decoration: none;
  transition: top var(--transition-base) ease;
}

.skip-link:focus {
  top: 12px;
  outline: none;
  box-shadow: 0 0 0 4px rgba(255, 215, 0, 0.35);
}

/* ---------- 4. Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 200;
  background: var(--ms-midnight);
  color: var(--ms-white);
  border-bottom: 3px solid var(--ms-red);
}

.site-header::before {
  content: '';
  position: absolute;
  top: 0;
  right: -5%;
  width: 260px;
  height: 100%;
  background: repeating-linear-gradient(
    -45deg,
    transparent 0,
    transparent 12px,
    rgba(212, 0, 0, 0.08) 12px,
    rgba(212, 0, 0, 0.08) 16px
  );
  pointer-events: none;
  z-index: 0;
}

.site-header::after {
  content: '';
  position: absolute;
  bottom: -3px;
  right: 0;
  width: 18%;
  height: 3px;
  background: var(--ms-gold);
  z-index: 1;
}

.header-shell {
  position: relative;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 4vw;
  z-index: 1;
}

.masthead {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  padding: 22px 0 14px;
  gap: var(--space-3);
}

.masthead-live {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  justify-self: start;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  color: rgba(255, 255, 255, 0.6);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-pill);
  padding: 6px 14px;
}

.live-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--ms-red);
  box-shadow: 0 0 0 0 rgba(212, 0, 0, 0.6);
  animation: livePulse 2s infinite;
}

.live-text {
  letter-spacing: 0.08em;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--ms-white);
  grid-column: 2;
  justify-self: center;
}

.brand:hover {
  color: var(--ms-white);
  opacity: 0.92;
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  background: var(--ms-red);
  color: var(--ms-white);
  border-radius: 14px;
  font-family: var(--font-head);
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  line-height: 1;
  position: relative;
  box-shadow: 0 4px 14px rgba(212, 0, 0, 0.4);
}

.brand-mark::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--ms-gold);
  border-radius: 999px;
  transform: translateX(0) rotate(-2deg);
  transform-origin: left center;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
  gap: 2px;
}

.brand-name {
  font-family: var(--font-head);
  font-size: 1.6rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  line-height: 1;
  text-transform: uppercase;
}

.brand-sub {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  color: var(--ms-gold);
  letter-spacing: 0.22em;
  text-transform: uppercase;
  font-weight: 500;
}

.masthead-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  grid-column: 3;
  justify-self: end;
}

.header-cta {
  flex-shrink: 0;
  box-shadow: var(--shadow-red);
}

.nav-toggle {
  display: none;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 12px;
  cursor: pointer;
  padding: 0;
  transition: background var(--transition-base) ease, border-color var(--transition-base) ease;
}

.nav-toggle:hover {
  background: rgba(255, 255, 255, 0.16);
  border-color: rgba(255, 255, 255, 0.3);
}

.nav-toggle-box {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 20px;
}

.nav-toggle-line {
  display: block;
  height: 2px;
  border-radius: 2px;
  background: var(--ms-white);
  transition: transform var(--transition-base) ease, opacity var(--transition-base) ease;
}

.main-nav {
  display: flex;
  justify-content: center;
  flex-wrap: nowrap;
  gap: 6px;
  padding: 0 0 16px;
}

.main-nav a {
  display: inline-flex;
  align-items: center;
  padding: 10px 18px;
  border-radius: var(--radius-pill);
  color: rgba(255, 255, 255, 0.82);
  font-family: var(--font-head);
  font-size: 0.88rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  line-height: 1;
  text-decoration: none;
  white-space: nowrap;
  transition: background var(--transition-base) ease, color var(--transition-base) ease, transform var(--transition-base) ease, box-shadow var(--transition-base) ease;
}

.main-nav a:hover {
  background: rgba(255, 255, 255, 0.1);
  color: var(--ms-gold);
  transform: translateY(-1px);
}

.main-nav a[aria-current="page"] {
  background: var(--ms-red);
  color: var(--ms-white);
  box-shadow: 0 4px 14px rgba(212, 0, 0, 0.38);
}

.main-nav a[aria-current="page"]:hover {
  color: var(--ms-white);
  background: #e60000;
}

/* ---------- 5. Footer ---------- */
.site-footer {
  position: relative;
  background: var(--ms-dark);
  color: rgba(255, 255, 255, 0.75);
  border-top: 4px solid var(--ms-red);
}

.site-footer::before {
  content: '';
  position: absolute;
  top: -4px;
  left: 0;
  width: 30%;
  height: 4px;
  background: var(--ms-gold);
  z-index: 1;
}

.footer-shell {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 64px 4vw 28px;
}

.footer-main {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.2fr;
  gap: 48px;
}

.footer-brand-block {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.footer-trust {
  margin: 0;
  max-width: 42ch;
  font-size: 0.9rem;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.55);
}

.footer-contact-compact {
  display: flex;
  flex-direction: column;
  gap: 4px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  line-height: 1.6;
  color: rgba(255, 255, 255, 0.4);
}

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

.footer-col-title {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.15);
  font-family: var(--font-head);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ms-white);
}

.footer-col-title::before {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 2px;
  background: var(--ms-red);
  transform: rotate(45deg);
  flex-shrink: 0;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: rgba(255, 255, 255, 0.65);
  text-decoration: none;
  font-size: 0.9rem;
  line-height: 1.4;
  transition: color var(--transition-base) ease, padding-left var(--transition-base) ease;
}

.footer-links a::before {
  content: '';
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--ms-red);
  flex-shrink: 0;
  opacity: 0.7;
}

.footer-links a:hover {
  color: var(--ms-gold);
  padding-left: 4px;
}

.footer-links-stack {
  gap: 8px;
  font-size: 0.85rem;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.5);
}

.footer-links-stack span {
  display: block;
}

.footer-col-contact .footer-links a::before {
  display: none;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 24px;
  margin-top: 48px;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  font-size: 0.78rem;
  color: rgba(255, 255, 255, 0.4);
}

.footer-bottom-sep {
  width: 1px;
  height: 14px;
  background: rgba(255, 255, 255, 0.25);
}

[data-year] {
  font-family: var(--font-mono);
}

/* ---------- 6. Back to Top ---------- */
.back-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 90;
  width: 48px;
  height: 48px;
  border: none;
  border-radius: var(--radius-pill);
  background: var(--ms-red);
  color: var(--ms-white);
  font-size: 1.25rem;
  line-height: 1;
  cursor: pointer;
  box-shadow: var(--shadow-red);
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity var(--transition-base) ease, transform var(--transition-base) ease, visibility var(--transition-base) ease, background var(--transition-base) ease;
}

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

.back-top:hover {
  background: #e60000;
  transform: translateY(-3px);
}

/* ---------- 7. Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  border-radius: var(--radius-pill);
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 600;
  line-height: 1;
  text-decoration: none;
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform var(--transition-base) ease, box-shadow var(--transition-base) ease, background var(--transition-base) ease, border-color var(--transition-base) ease, color var(--transition-base) ease;
}

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

.btn-primary {
  background: var(--ms-red);
  color: var(--ms-white);
  box-shadow: var(--shadow-red);
}

.btn-primary:hover {
  background: #e60000;
  color: var(--ms-white);
  box-shadow: 0 8px 24px rgba(212, 0, 0, 0.45);
}

.btn-outline {
  background: transparent;
  color: var(--ms-text);
  border-color: var(--ms-text);
}

.btn-outline:hover {
  border-color: var(--ms-red);
  color: var(--ms-red);
}

.btn-compact {
  padding: 10px 20px;
  font-size: 0.85rem;
}

/* ---------- 8. Badges ---------- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  background: var(--ms-red);
  color: var(--ms-white);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  line-height: 1.4;
  white-space: nowrap;
}

.badge-gold {
  background: var(--ms-gold);
  color: var(--ms-dark);
}

.badge-ghost {
  background: rgba(255, 255, 255, 0.12);
  color: var(--ms-white);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

/* ---------- 9. Layout Utilities ---------- */
.container {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 4vw;
}

.section {
  padding: var(--space-6) 0;
}

.section-head {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: var(--space-4);
}

.section-title {
  font-family: var(--font-head);
  font-size: clamp(1.75rem, 3vw, 2.5rem);
  font-weight: 700;
  line-height: 1.15;
  color: var(--ms-text);
  margin: 0;
}

.section-sub {
  color: var(--ms-muted);
  font-size: 0.95rem;
  max-width: 60ch;
}

.grid {
  display: grid;
  gap: var(--space-3);
}

.grid-2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.split-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.2fr);
  gap: 48px;
  align-items: start;
}

.split-aside {
  padding-right: 32px;
  border-right: 2px solid var(--ms-red);
  position: sticky;
  top: 130px;
}

.split-content {
  min-width: 0;
}

.bg-white {
  background: var(--ms-white);
  color: var(--ms-text);
}

.bg-light {
  background: var(--ms-gray);
  color: var(--ms-text);
}

.bg-midnight {
  background: var(--ms-midnight);
  color: var(--ms-white);
}

/* ---------- 10. Page Header & Breadcrumbs ---------- */
.page-header {
  position: relative;
  padding: 56px 0 48px;
  background: linear-gradient(135deg, var(--ms-midnight) 0%, var(--ms-dark) 100%);
  color: var(--ms-white);
  overflow: hidden;
}

.page-header::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--ms-red) 70%, var(--ms-gold) 70%);
}

.page-header-title {
  font-family: var(--font-head);
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  line-height: 1.1;
  margin: 0;
  letter-spacing: 0.03em;
}

.page-header-sub {
  margin: 8px 0 0;
  font-size: 1rem;
  color: rgba(255, 255, 255, 0.7);
  max-width: 60ch;
}

.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 12px 0;
  font-size: 0.8rem;
  color: var(--ms-muted);
}

.breadcrumbs a {
  color: var(--ms-text);
  text-decoration: none;
}

.breadcrumbs a:hover {
  color: var(--ms-red);
}

.breadcrumbs-on-dark {
  color: rgba(255, 255, 255, 0.6);
}

.breadcrumbs-on-dark a {
  color: rgba(255, 255, 255, 0.9);
}

.breadcrumbs-on-dark a:hover {
  color: var(--ms-gold);
}

/* ---------- 11. Content Block ---------- */
.content-block {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 48px 4vw 64px;
}

.content-block p {
  max-width: 72ch;
  line-height: 1.8;
}

/* ---------- 12. Cards ---------- */
.card {
  background: var(--ms-white);
  border-radius: var(--radius-lg);
  padding: var(--space-3);
  border: 1px solid rgba(0, 0, 0, 0.06);
  box-shadow: var(--shadow-card);
  transition: transform var(--transition-base) ease, box-shadow var(--transition-base) ease;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-float);
}

.card-raise {
  position: relative;
  overflow: hidden;
}

.card-raise::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--ms-red), var(--ms-gold));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-slow) ease;
}

.card-raise:hover::before {
  transform: scaleX(1);
}

/* ---------- 13. Data Number ---------- */
.data-num {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 1.6rem;
  line-height: 1;
  color: var(--ms-red);
  font-variant-numeric: tabular-nums;
}

/* ---------- 14. Divider ---------- */
.divider {
  height: 4px;
  border: none;
  border-radius: 4px;
  background: linear-gradient(90deg, var(--ms-red), var(--ms-gold));
  margin: var(--space-4) 0;
}

/* ---------- 15. Media Frame ---------- */
.media-frame {
  position: relative;
  display: block;
  overflow: hidden;
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, var(--ms-midnight) 0%, var(--ms-dark) 100%);
}

.media-frame::before {
  content: '';
  display: block;
  padding-top: 56.25%;
}

.media-frame img,
.media-frame video {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow) ease;
}

.media-frame:hover img {
  transform: scale(1.03);
}

.media-frame-4-3::before {
  padding-top: 75%;
}

.media-frame-square::before {
  padding-top: 100%;
}

.media-frame-portrait::before {
  padding-top: 120%;
}

/* ---------- 16. Expandable Groups ---------- */
.expand-btn {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  width: 100%;
  padding: 16px 20px;
  border: 1px solid rgba(0, 0, 0, 0.08);
  border-radius: var(--radius-md);
  background: var(--ms-white);
  font-size: 1rem;
  font-weight: 600;
  color: var(--ms-text);
  cursor: pointer;
  text-align: left;
  box-shadow: var(--shadow-card);
  transition: background var(--transition-base) ease, box-shadow var(--transition-base) ease, border-color var(--transition-base) ease;
}

.expand-btn:hover {
  background: #fafafa;
  border-color: var(--ms-red);
  box-shadow: var(--shadow-float);
}

.expand-btn::after {
  content: '+';
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 400;
  line-height: 1;
  color: var(--ms-red);
  flex-shrink: 0;
  transition: transform var(--transition-base) ease;
}

.expand-btn[aria-expanded="true"]::after {
  transform: rotate(45deg);
}

.expand-panel {
  margin-top: 8px;
}

.expand-panel:not([hidden]) {
  animation: expandIn var(--transition-base) ease;
}

/* ---------- 17. Animations ---------- */
@keyframes livePulse {
  0% {
    box-shadow: 0 0 0 0 rgba(212, 0, 0, 0.5);
  }
  70% {
    box-shadow: 0 0 0 8px rgba(212, 0, 0, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(212, 0, 0, 0);
  }
}

@keyframes expandIn {
  from {
    opacity: 0;
    transform: translateY(-4px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ---------- 18. Responsive ---------- */
@media (max-width: 1024px) {
  .grid-3,
  .grid-4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .footer-main {
    grid-template-columns: 1fr 1fr;
    gap: 40px;
  }

  .split-layout {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 32px;
  }

  .split-aside {
    padding-right: 20px;
  }

  .main-nav a {
    padding: 9px 14px;
    font-size: 0.82rem;
  }
}

@media (max-width: 768px) {
  .masthead {
    grid-template-columns: auto auto;
    padding: 16px 0 12px;
    gap: 12px;
  }

  .brand {
    grid-column: 1;
    justify-self: start;
  }

  .masthead-live {
    display: none;
  }

  .masthead-actions {
    grid-column: 2;
    justify-self: end;
  }

  .header-cta {
    padding: 9px 16px;
    font-size: 0.8rem;
  }

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

  .main-nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    max-width: none;
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
    padding: 12px 20px 20px;
    background: var(--ms-dark);
    border-top: 2px solid var(--ms-red);
    border-radius: 0 0 20px 20px;
    box-shadow: 0 16px 32px rgba(0, 0, 0, 0.35);
  }

  .main-nav[data-open] {
    display: flex;
  }

  .main-nav a {
    border-radius: 12px;
    padding: 13px 16px;
    font-size: 0.95rem;
  }

  .main-nav a[aria-current="page"] {
    border-radius: 12px;
  }

  .nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

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

  .nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }

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

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

  .split-aside {
    position: static;
    padding-right: 0;
    border-right: none;
    border-bottom: 2px solid var(--ms-red);
    padding-bottom: 20px;
    margin-bottom: 24px;
  }

  .footer-main {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }

  .footer-bottom-sep {
    display: none;
  }

  .back-top {
    right: 16px;
    bottom: 16px;
    width: 44px;
    height: 44px;
  }

  .page-header {
    padding: 40px 0 36px;
  }
}

@media (max-width: 480px) {
  .brand-mark {
    width: 36px;
    height: 36px;
    font-size: 1rem;
    border-radius: 10px;
  }

  .brand-name {
    font-size: 1.1rem;
    letter-spacing: 0.08em;
  }

  .brand-sub {
    font-size: 0.55rem;
    letter-spacing: 0.14em;
  }

  .header-cta {
    padding: 8px 12px;
    font-size: 0.75rem;
  }

  .masthead-actions {
    gap: 8px;
  }
}

/* ---------- 19. Reduced Motion ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  html {
    scroll-behavior: auto;
  }

  .live-dot {
    box-shadow: none;
  }
}