/* ==========================================================
   米兰主场 · 全站共享样式 /assets/site.css
   ========================================================== */

/* ---------- 1. Design tokens ---------- */
:root {
  color-scheme: dark;

  --color-red: #D40000;
  --color-black: #111111;
  --color-gold: #FFC700;
  --color-deep-red: #8B0000;
  --color-panel: #1A1A1A;
  --color-white: #FFFFFF;
  --color-gray: #B0B0B0;
  --color-speedline: #FF4444;
  --color-green: #00E676;

  --font-heading: 'Noto Sans SC', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --font-body: 'Noto Sans SC', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --font-data: 'Roboto Mono', 'SF Mono', 'Cascadia Code', Consolas, monospace;

  --container-width: 1200px;
  --radius-pill: 999px;
  --radius-card: 1.25rem;
  --radius-small: 0.75rem;

  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --speed-fast: 0.25s;
  --speed-med: 0.45s;
}

/* ---------- 2. Reset ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  scrollbar-color: var(--color-deep-red) var(--color-black);
}

body {
  font-family: var(--font-body);
  font-weight: 400;
  background-color: var(--color-black);
  background-image:
    radial-gradient(ellipse 50% 40% at 88% -2%, rgba(212, 0, 0, 0.10), transparent),
    radial-gradient(ellipse 40% 30% at 0% 100%, rgba(255, 199, 0, 0.04), transparent);
  background-attachment: fixed;
  color: var(--color-white);
  line-height: 1.75;
  min-height: 100vh;
  overflow-x: clip;
}

h1, h2, h3, h4 {
  font-family: var(--font-heading);
  font-weight: 900;
  line-height: 1.2;
  letter-spacing: -0.02em;
  text-wrap: balance;
}

p {
  text-wrap: pretty;
}

a {
  color: var(--color-gold);
  text-decoration: none;
  transition: color var(--speed-fast) var(--ease-out);
}

a:hover {
  color: var(--color-white);
}

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

ul, ol {
  list-style: none;
}

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

/* ---------- 3. Utilities ---------- */
.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  border: 0;
  clip-path: inset(50%);
  overflow: hidden;
  white-space: nowrap;
}

.text-center {
  text-align: center;
}

[data-reveal] {
  opacity: 0;
  transform: translateY(28px);
  transition:
    opacity 0.7s var(--ease-out) var(--reveal-delay, 0ms),
    transform 0.7s var(--ease-out) var(--reveal-delay, 0ms);
}

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

/* ---------- 4. Focus, selection, scrollbar ---------- */
:focus-visible {
  outline: 2px solid var(--color-gold);
  outline-offset: 3px;
  border-radius: 2px;
}

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

::-webkit-scrollbar {
  width: 10px;
}

::-webkit-scrollbar-track {
  background: #0A0A0A;
}

::-webkit-scrollbar-thumb {
  background: var(--color-deep-red);
  border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-red);
}

/* ---------- 5. Layout ---------- */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin-inline: auto;
  padding-inline: clamp(1rem, 4vw, 2rem);
}

.page-main {
  padding-block: 2.5rem 5rem;
}

.grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: clamp(1rem, 2.5vw, 1.5rem);
}

.grid-item {
  grid-column: span 6;
}

.section {
  padding-block: 3rem;
}

.section--dark {
  background-color: var(--color-panel);
  border-block: 1px solid rgba(255, 255, 255, 0.06);
}

.section-head {
  display: flex;
  align-items: baseline;
  gap: 0.875rem;
  margin-bottom: 2rem;
}

.section-head::after {
  content: '';
  flex: 1;
  height: 1px;
  align-self: center;
  background: linear-gradient(90deg, rgba(212, 0, 0, 0.5), transparent);
}

.section-number {
  font-family: var(--font-data);
  font-size: 0.9375rem;
  color: var(--color-gold);
  font-weight: 700;
  letter-spacing: 0.08em;
}

.section-title {
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.1;
}

.page-head {
  padding-top: 2rem;
  padding-bottom: 2.5rem;
}

.page-head-title {
  font-size: clamp(2rem, 5vw, 3.5rem);
  line-height: 1.15;
  margin-top: 0.5rem;
}

/* ---------- 6. Breadcrumb ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.375rem;
  font-family: var(--font-data);
  font-size: 0.8125rem;
  color: var(--color-gray);
  margin-bottom: 0.75rem;
}

.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.375rem;
}

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

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

.breadcrumb-item:not(:last-child)::after {
  content: '/';
  margin-left: 0.375rem;
  color: rgba(255, 255, 255, 0.25);
}

.breadcrumb-item[aria-current='page'] {
  color: var(--color-white);
}

/* ---------- 7. Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-pill);
  font-weight: 700;
  font-size: 0.9375rem;
  line-height: 1.2;
  text-decoration: none;
  border: 1px solid transparent;
  transition:
    background var(--speed-fast) var(--ease-out),
    color var(--speed-fast) var(--ease-out),
    transform var(--speed-fast) var(--ease-out),
    border-color var(--speed-fast) var(--ease-out);
}

.btn:active {
  transform: scale(0.97);
}

.btn-primary {
  background: var(--color-red);
  color: var(--color-white);
  box-shadow: 0 4px 16px rgba(212, 0, 0, 0.35);
}

.btn-primary:hover {
  background: var(--color-gold);
  color: var(--color-black);
  transform: rotate(-1deg) scale(1.02);
}

.btn-ghost {
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.25);
  color: var(--color-white);
}

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

/* ---------- 8. Cards ---------- */
.card {
  background: var(--color-panel);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: var(--radius-card);
  padding: 1.5rem;
  transition:
    transform var(--speed-med) var(--ease-out),
    border-color var(--speed-med) var(--ease-out),
    box-shadow var(--speed-med) var(--ease-out);
}

.card:hover {
  transform: translateY(-4px);
  border-color: rgba(255, 199, 0, 0.35);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.35);
}

.card--angled {
  clip-path: polygon(0 0, calc(100% - 1.25rem) 0, 100% 1.25rem, 100% 100%, 1.25rem 100%, 0 calc(100% - 1.25rem));
}

.card-title {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
}

.card-body {
  color: var(--color-gray);
  font-size: 0.9375rem;
  line-height: 1.7;
}

/* ---------- 9. Data & tags ---------- */
.data-label {
  font-family: var(--font-data);
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-gray);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.data-value {
  font-family: var(--font-data);
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  font-weight: 700;
  color: var(--color-gold);
  line-height: 1.1;
}

.tag {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  border-radius: var(--radius-pill);
  background: rgba(212, 0, 0, 0.14);
  color: #FF7B7B;
  font-family: var(--font-data);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.tag--gold {
  background: rgba(255, 199, 0, 0.12);
  color: var(--color-gold);
}

/* ---------- 10. Image frame ---------- */
.image-frame {
  position: relative;
  border-radius: var(--radius-card);
  overflow: hidden;
  background: var(--color-panel);
  border: 1px solid rgba(255, 255, 255, 0.06);
  aspect-ratio: 16 / 9;
  min-height: 8rem;
}

.image-frame::before {
  content: attr(data-placeholder);
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  text-align: center;
  font-family: var(--font-data);
  font-size: 0.8125rem;
  color: var(--color-gray);
  letter-spacing: 0.05em;
  background:
    repeating-linear-gradient(45deg, rgba(255, 255, 255, 0.025) 0 1px, transparent 1px 12px),
    radial-gradient(ellipse at 70% 20%, rgba(212, 0, 0, 0.12), transparent);
}

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

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

/* ---------- 11. Decorative ---------- */
.speedlines-bg {
  background-image: repeating-linear-gradient(
    -45deg,
    rgba(255, 68, 68, 0.05) 0,
    rgba(255, 68, 68, 0.05) 1px,
    transparent 1px,
    transparent 12px
  );
}

/* ---------- 12. Skip link & scroll progress ---------- */
.skip-link {
  position: fixed;
  top: -100px;
  left: 1rem;
  z-index: 300;
  background: var(--color-gold);
  color: var(--color-black);
  padding: 0.75rem 1.5rem;
  border-radius: 0 0 var(--radius-small) var(--radius-small);
  font-weight: 700;
  font-size: 0.9375rem;
  text-decoration: none;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.4);
  transition: top 0.2s ease;
}

.skip-link:focus-visible {
  top: 0;
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 400;
  height: 3px;
  width: 0;
  background: linear-gradient(90deg, var(--color-red), var(--color-gold));
  box-shadow: 0 0 8px rgba(255, 199, 0, 0.35);
  transition: width 0.1s linear;
}

/* ---------- 13. Header ---------- */
.site-header {
  position: sticky;
  top: 0.75rem;
  z-index: 100;
  padding-inline: 1rem;
}

.header-inner {
  position: relative;
  max-width: 1280px;
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.6rem 0.75rem 0.6rem 1.25rem;
  background: rgba(17, 17, 17, 0.88);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-pill);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  box-shadow:
    0 12px 40px rgba(0, 0, 0, 0.55),
    inset 0 1px 0 rgba(255, 255, 255, 0.04);
}

.site-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--color-white);
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 1.25rem;
  letter-spacing: 0.02em;
  white-space: nowrap;
  text-decoration: none;
}

.site-brand:hover {
  color: var(--color-gold);
}

.brand-mark {
  position: relative;
  flex-shrink: 0;
  width: 1.75rem;
  height: 1.75rem;
  background: var(--color-red);
  clip-path: polygon(50% 0, 100% 50%, 50% 100%, 0 50%);
  box-shadow: 0 2px 10px rgba(212, 0, 0, 0.45);
}

.brand-mark::after {
  content: '';
  position: absolute;
  inset: 28%;
  background: var(--color-gold);
  clip-path: polygon(50% 0, 100% 50%, 50% 100%, 0 50%);
}

.brand-text {
  font-size: 1.35rem;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.3125rem;
  width: 2.75rem;
  height: 2.75rem;
  border-radius: 50%;
  background: var(--color-panel);
  border: 1px solid rgba(255, 255, 255, 0.12);
  transition:
    border-color var(--speed-fast) var(--ease-out),
    background var(--speed-fast) var(--ease-out);
}

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

.nav-toggle-bar {
  width: 1.25rem;
  height: 2px;
  border-radius: 2px;
  background: var(--color-white);
  transition:
    transform var(--speed-fast) var(--ease-out),
    opacity var(--speed-fast) var(--ease-out);
}

.nav-toggle[aria-expanded='true'] .nav-toggle-bar:nth-child(1) {
  transform: translateY(0.3125rem) 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(-0.3125rem) rotate(-45deg);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 0.125rem;
}

.nav-list a {
  display: block;
  padding: 0.5rem 0.875rem;
  border-radius: var(--radius-pill);
  color: var(--color-gray);
  font-size: 0.875rem;
  font-weight: 500;
  text-decoration: none;
  white-space: nowrap;
  transition:
    background var(--speed-fast) var(--ease-out),
    color var(--speed-fast) var(--ease-out);
}

.nav-list a:hover {
  color: var(--color-white);
  background: rgba(255, 255, 255, 0.06);
}

.nav-list a[aria-current='page'] {
  color: var(--color-gold);
  background: rgba(255, 199, 0, 0.1);
  box-shadow: inset 0 -2px 0 rgba(255, 199, 0, 0.35);
}

.nav-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.5rem 1.125rem;
  border-radius: var(--radius-pill);
  background: var(--color-red);
  color: var(--color-white);
  font-weight: 700;
  font-size: 0.875rem;
  text-decoration: none;
  white-space: nowrap;
  box-shadow: 0 3px 14px rgba(212, 0, 0, 0.4);
  transition:
    background var(--speed-fast) var(--ease-out),
    color var(--speed-fast) var(--ease-out),
    transform var(--speed-fast) var(--ease-out);
}

.nav-cta:hover {
  background: var(--color-gold);
  color: var(--color-black);
  transform: rotate(-2deg);
}

.nav-cta-arrow {
  font-family: var(--font-data);
  font-weight: 700;
  transition: transform var(--speed-fast) var(--ease-out);
}

.nav-cta:hover .nav-cta-arrow {
  transform: translateX(3px);
}

/* ---------- 14. Footer ---------- */
.site-footer {
  position: relative;
  margin-top: 4rem;
  background-color: #0A0A0A;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  overflow: hidden;
}

.site-footer::before {
  content: '';
  display: block;
  height: 4px;
  background: linear-gradient(90deg, var(--color-red), var(--color-gold) 50%, var(--color-red));
}

.site-footer::after {
  content: '';
  position: absolute;
  top: 0;
  right: -10%;
  width: 60%;
  height: 100%;
  background: radial-gradient(ellipse at center, rgba(212, 0, 0, 0.08), transparent 70%);
  pointer-events: none;
}

.footer-banner {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 3rem 1rem 0;
  user-select: none;
}

.footer-banner-text {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: clamp(3.5rem, 12vw, 9rem);
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1px rgba(255, 255, 255, 0.08);
  text-transform: uppercase;
  letter-spacing: 0.03em;
  white-space: nowrap;
}

.footer-main {
  display: grid;
  grid-template-columns: minmax(0, 2fr) minmax(0, 1fr) minmax(0, 1fr) minmax(0, 1.4fr);
  gap: clamp(1.5rem, 4vw, 3rem);
  padding-block: 3rem;
}

.footer-logo {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 1.75rem;
  color: var(--color-white);
  margin-bottom: 0.75rem;
  letter-spacing: 0.02em;
}

.footer-statement {
  max-width: 34ch;
  color: var(--color-gray);
  font-size: 0.875rem;
  line-height: 1.85;
}

.footer-heading {
  position: relative;
  font-size: 0.8125rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--color-gray);
  margin-bottom: 1.25rem;
  padding-left: 0.875rem;
}

.footer-heading::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.5rem;
  width: 5px;
  height: 5px;
  background: var(--color-gold);
  transform: rotate(45deg);
}

.footer-links li {
  margin-bottom: 0.625rem;
}

.footer-links a {
  display: inline-block;
  color: var(--color-gray);
  font-size: 0.875rem;
  text-decoration: none;
  transition:
    color var(--speed-fast) var(--ease-out),
    padding-left var(--speed-fast) var(--ease-out);
}

.footer-links a:hover {
  color: var(--color-gold);
  padding-left: 0.25rem;
}

.footer-contact-list li {
  display: flex;
  gap: 0.5rem;
  color: var(--color-gray);
  font-size: 0.875rem;
  line-height: 1.6;
  margin-bottom: 0.625rem;
}

.footer-contact-label {
  flex-shrink: 0;
  font-family: var(--font-data);
  font-size: 0.75rem;
  color: var(--color-gold);
  padding-top: 2px;
}

.footer-contact-note {
  font-size: 0.75rem;
  color: rgba(176, 176, 176, 0.7);
  line-height: 1.7;
  margin-top: 0.875rem;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding: 1.25rem clamp(1rem, 4vw, 2rem);
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 0.5rem 1.5rem;
  font-family: var(--font-data);
  font-size: 0.8125rem;
  color: var(--color-gray);
}

/* ---------- 15. Back top ---------- */
.back-top {
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  z-index: 90;
  width: 3rem;
  height: 3rem;
  border-radius: 50%;
  background: var(--color-red);
  color: var(--color-white);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 6px 24px rgba(212, 0, 0, 0.4);
  border: 1px solid rgba(255, 255, 255, 0.12);
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition:
    background var(--speed-fast) var(--ease-out),
    transform var(--speed-fast) var(--ease-out),
    opacity var(--speed-fast) var(--ease-out),
    visibility var(--speed-fast) var(--ease-out);
}

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

.back-top:hover {
  background: var(--color-gold);
  color: var(--color-black);
}

.back-top-arrow {
  display: block;
  font-family: var(--font-data);
  font-size: 1.125rem;
  line-height: 1;
  transform: translateY(-1px);
}

/* ---------- 16. Responsive ---------- */
@media (max-width: 920px) {
  .site-header {
    padding-inline: 0.75rem;
  }

  .header-inner {
    padding: 0.5rem 0.5rem 0.5rem 1rem;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    top: calc(100% + 0.75rem);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0.5rem;
    padding: 1rem;
    border-radius: var(--radius-card);
    background: rgba(17, 17, 17, 0.97);
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 24px 50px rgba(0, 0, 0, 0.65);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-0.75rem);
    pointer-events: none;
    transition:
      opacity var(--speed-fast) var(--ease-out),
      transform var(--speed-fast) var(--ease-out),
      visibility var(--speed-fast) var(--ease-out);
  }

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

  .nav-list {
    flex-direction: column;
    align-items: stretch;
  }

  .nav-list a {
    padding: 0.75rem 1rem;
    border-radius: var(--radius-small);
    font-size: 0.9375rem;
  }

  .nav-cta {
    justify-content: center;
    padding: 0.75rem 1rem;
    margin-top: 0.25rem;
  }

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

  .footer-brand {
    grid-column: 1 / -1;
  }

  .grid-item {
    grid-column: span 6;
  }
}

@media (max-width: 640px) {
  .section {
    padding-block: 2rem;
  }

  .page-main {
    padding-block: 1.5rem 3rem;
  }

  .footer-main {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .footer-brand {
    grid-column: auto;
  }

  .footer-bottom {
    flex-direction: column;
    justify-content: center;
    text-align: center;
  }

  .back-top {
    right: 1rem;
    bottom: 1rem;
  }

  .grid-item {
    grid-column: span 12;
  }
}

/* ---------- 17. Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition-duration: 0.001s !important;
    animation-duration: 0.001s !important;
  }

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

  .skip-link {
    transition: none;
  }
}