/* =====================================================================
   博奥体育 · 共享样式表  /assets/site.css
   深夜看台配色 · 粗野主义边框 · 88px 侧边品牌轨道
   ===================================================================== */

/* ---------- 1. Reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

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

body, h1, h2, h3, h4, h5, p, ul, ol, li, figure, blockquote, dl, dd, fieldset, legend { margin: 0; }

ul, ol { padding: 0; list-style: none; }

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

button, input, select, textarea { font: inherit; color: inherit; }

button { background: none; border: 0; padding: 0; cursor: pointer; }

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

table { border-collapse: collapse; width: 100%; }

hr { border: 0; border-top: 1px solid rgba(108, 135, 151, .3); margin: 0; }

/* ---------- 2. Tokens ---------- */
:root {
  --ink: #0A1A2A;
  --ink-2: #12293D;
  --edge: #050D15;
  --steel: #6C8797;
  --mist: #A9BEC9;
  --paper: #F4F1E9;
  --cream: #E7DFCE;
  --amber: #E4892C;
  --ember: #C2542A;
  --jade: #4E8C86;
  --brown: #1B1512;

  --rail-w: 88px;
  --bar-h: 56px;
  --maxw: 1180px;
  --pad: 20px;

  --ff-display: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", serif;
  --ff-label: "Archivo Narrow", "Oswald", "Arial Narrow", Arial, sans-serif;
  --ff-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  --ff-mono: "IBM Plex Mono", "Roboto Mono", ui-monospace, Consolas, "Courier New", monospace;

  --line: 2px solid var(--edge);
  --shadow: 6px 6px 0 var(--edge);
}

@media (min-width: 1024px) {
  :root { --bar-h: 72px; }
}

@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}

/* ---------- 3. Base ---------- */
body {
  background-color: var(--ink);
  color: var(--paper);
  font-family: var(--ff-body);
  font-size: 16px;
  line-height: 1.85;
  letter-spacing: .01em;
  padding-top: var(--bar-h);
  padding-bottom: 60px;
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

@media (min-width: 1024px) {
  body {
    padding-left: var(--rail-w);
    padding-bottom: 0;
  }
}

#main-content { display: block; scroll-margin-top: calc(var(--bar-h) + 16px); }
#main-content:focus { outline: none; }

h1, h2, h3, h4, h5 {
  font-family: var(--ff-display);
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -.01em;
}

h1 { font-size: 30px; }
h2 { font-size: 24px; }
h3 { font-size: 20px; }
h4 { font-size: 16px; }

@media (min-width: 768px) {
  h1 { font-size: 40px; }
  h2 { font-size: 28px; }
}

@media (min-width: 1024px) {
  h1 { font-size: 64px; }
  h2 { font-size: 40px; }
}

p + p { margin-top: 1.2em; }

.eyebrow {
  font-family: var(--ff-label);
  font-size: 13px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--ember);
}

.lede { font-size: 17px; line-height: 1.9; color: var(--mist); max-width: 56ch; }

.num {
  font-family: var(--ff-mono);
  font-size: .94em;
  letter-spacing: .04em;
  font-variant-numeric: tabular-nums;
}

.band--cream .eyebrow { color: var(--ember); }
.band--cream .lede { color: #4A3B32; }

/* ---------- 4. Focus & skip ---------- */
:focus-visible {
  outline: 2px solid var(--amber);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  top: -80px;
  left: 8px;
  z-index: 200;
  padding: 12px 20px;
  background: var(--amber);
  color: var(--brown);
  font-family: var(--ff-label);
  font-size: 13px;
  letter-spacing: .14em;
  text-transform: uppercase;
  border: 2px solid var(--edge);
  box-shadow: var(--shadow);
  transition: top .18s ease;
}

.skip-link:focus { top: 8px; }

@media (min-width: 1024px) {
  .skip-link { left: calc(var(--rail-w) + 8px); }
}

/* ---------- 5. Brand rail ---------- */
.rail { display: none; }

@media (min-width: 1024px) {
  .rail {
    position: fixed;
    left: 0;
    top: 0;
    bottom: 0;
    width: var(--rail-w);
    z-index: 90;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: space-between;
    padding: 20px 0 22px;
    background: var(--ink-2);
    border-right: 2px solid var(--edge);
  }

  .rail__brand {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
    padding: 6px 0;
  }

  .rail__cn {
    writing-mode: vertical-rl;
    font-family: var(--ff-display);
    font-weight: 700;
    font-size: 17px;
    letter-spacing: .26em;
    color: var(--paper);
  }

  .rail__en {
    writing-mode: vertical-rl;
    font-family: var(--ff-label);
    font-size: 10px;
    letter-spacing: .34em;
    text-transform: uppercase;
    color: var(--steel);
  }

  .rail__ticks {
    flex: 1;
    width: 2px;
    margin: 20px 0;
    background: repeating-linear-gradient(to bottom, var(--steel) 0 1px, transparent 1px 10px);
    opacity: .55;
  }

  .rail__marker {
    position: absolute;
    left: 0;
    top: 132px;
    width: 3px;
    height: 64px;
    background: var(--ember);
    transition: transform .24s ease-out;
  }

  .rail__foot {
    writing-mode: vertical-rl;
    font-family: var(--ff-label);
    font-size: 10px;
    letter-spacing: .24em;
    color: var(--steel);
  }
}

/* ---------- 6. Header bar ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 80;
}

@media (min-width: 1024px) {
  .site-header { left: var(--rail-w); }
}

.read-progress {
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 2px;
  z-index: 3;
  background: rgba(108, 135, 151, .25);
}

.read-progress__bar {
  display: block;
  width: 0;
  height: 100%;
  background: var(--amber);
}

.bar {
  height: var(--bar-h);
  background: transparent;
  color: var(--paper);
  border-bottom: 2px solid transparent;
  transition: background-color .24s ease, border-color .24s ease, color .24s ease;
}

.site-header[data-scrolled] .bar {
  background: var(--paper);
  color: var(--brown);
  border-bottom-color: var(--edge);
}

.bar__inner {
  display: flex;
  align-items: center;
  gap: 16px;
  height: 100%;
  width: 100%;
  max-width: var(--maxw);
  margin-left: 0;
  margin-right: auto;
  padding-left: var(--pad);
  padding-right: var(--pad);
}

.bar__brand {
  display: flex;
  flex-direction: column;
  justify-content: center;
  line-height: 1.25;
  margin-right: auto;
  min-height: 44px;
}

.bar__brand-name {
  font-family: var(--ff-display);
  font-weight: 700;
  font-size: 18px;
  letter-spacing: .06em;
}

@media (min-width: 1024px) {
  .bar__brand-name { font-size: 20px; }
}

.bar__brand-tag {
  display: none;
  font-family: var(--ff-label);
  font-size: 11px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--steel);
}

@media (min-width: 768px) {
  .bar__brand-tag { display: block; }
}

.site-header[data-scrolled] .bar__brand-tag { color: var(--ember); }

.bar__actions {
  display: none;
  align-items: center;
  gap: 10px;
}

@media (min-width: 1024px) {
  .bar__actions { display: flex; }
}

/* ---------- 7. Navigation ---------- */
.nav {
  display: flex;
  flex-direction: column;
  gap: 26px;
}

.nav__group {
  display: flex;
  flex-direction: column;
}

.nav__title {
  font-family: var(--ff-label);
  font-size: 12px;
  letter-spacing: .2em;
  text-transform: uppercase;
  color: var(--steel);
  padding-bottom: 10px;
  margin-bottom: 6px;
  border-bottom: 1px solid rgba(108, 135, 151, .3);
}

.nav__list {
  display: flex;
  flex-direction: column;
}

.nav__link {
  position: relative;
  display: flex;
  align-items: center;
  width: 100%;
  min-height: 52px;
  font-family: var(--ff-display);
  font-size: 20px;
  letter-spacing: .03em;
  color: inherit;
  border-bottom: 1px solid rgba(108, 135, 151, .16);
  transition: color .18s ease;
}

.nav__link:hover { color: var(--amber); }
.nav__link[aria-current="page"] { color: var(--amber); }

.nav__cta {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 8px;
}

@media (max-width: 1023px) {
  .nav {
    position: fixed;
    left: 0;
    right: 0;
    top: var(--bar-h);
    bottom: 0;
    z-index: 78;
    padding: 26px var(--pad) 100px;
    background: var(--ink);
    border-top: 2px solid var(--edge);
    overflow-y: auto;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: opacity .2s ease, transform .2s ease, visibility .2s linear;
  }

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

@media (min-width: 1024px) {
  .nav {
    position: static;
    flex-direction: row;
    align-items: center;
    gap: 26px;
    padding: 0;
    background: none;
    border: 0;
    overflow: visible;
    opacity: 1;
    visibility: visible;
    transform: none;
  }

  .nav__group { display: flex; align-items: center; }
  .nav__title { display: none; }
  .nav__list { flex-direction: row; align-items: center; gap: 22px; }
  .nav__cta { display: none; }

  .nav__link {
    width: auto;
    min-height: 44px;
    padding: 0 2px;
    font-family: var(--ff-label);
    font-size: 14px;
    letter-spacing: .12em;
    text-transform: uppercase;
    border-bottom: 0;
  }

  .nav__link::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: 10px;
    height: 2px;
    background: var(--ember);
    transform: scaleX(0);
    transform-origin: left center;
    transition: transform .2s ease-out;
  }

  .nav__link:hover::after,
  .nav__link:focus-visible::after,
  .nav__link[aria-current="page"]::after { transform: scaleX(1); }
}

.site-header[data-scrolled] .nav__link[aria-current="page"] { color: var(--ember); }

/* ---------- 8. Nav toggle ---------- */
.nav-toggle {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 44px;
  min-width: 44px;
  padding: 0 12px;
  border: 2px solid currentColor;
  font-family: var(--ff-label);
  font-size: 12px;
  letter-spacing: .16em;
  text-transform: uppercase;
  transition: color .18s ease, border-color .18s ease;
}

.nav-toggle__bars {
  position: relative;
  display: block;
  width: 18px;
  height: 2px;
  background: currentColor;
}

.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: currentColor;
  transition: transform .2s ease, top .2s ease;
}

.nav-toggle__bars::before { top: -6px; }
.nav-toggle__bars::after { top: 6px; }

.nav-toggle[aria-expanded="true"] .nav-toggle__bars { background: transparent; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before { top: 0; transform: rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after { top: 0; transform: rotate(-45deg); }

@media (min-width: 1024px) {
  .nav-toggle { display: none; }
}

/* ---------- 9. Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  padding: 0 16px;
  font-family: var(--ff-label);
  font-size: 13px;
  letter-spacing: .12em;
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform .16s ease, box-shadow .16s ease, background-color .16s ease,
    color .16s ease, border-color .16s ease;
}

.btn--amber {
  background: var(--amber);
  color: var(--brown);
  border-color: var(--edge);
  box-shadow: 4px 4px 0 var(--edge);
}

.btn--amber:hover { transform: translate(-2px, -2px); box-shadow: 6px 6px 0 var(--edge); }
.btn--amber:active { transform: translate(2px, 2px); box-shadow: 2px 2px 0 var(--edge); }

.btn--line {
  background: transparent;
  color: inherit;
  border-color: currentColor;
}

.btn--line:hover {
  background: var(--amber);
  color: var(--brown);
  border-color: var(--edge);
}

.btn--quiet {
  background: transparent;
  color: inherit;
  border-color: transparent;
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-underline-offset: 5px;
}

.btn--quiet:hover { color: var(--ember); }

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

/* ---------- 10. Mobile dock ---------- */
.dock {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 70;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 56px;
  padding: 0 18px;
  background: var(--ink-2);
  color: var(--paper);
  border-top: 2px solid var(--edge);
  font-family: var(--ff-label);
  font-size: 13px;
  letter-spacing: .14em;
}

.dock__label { flex: 1 1 auto; }
.dock__arrow { color: var(--amber); font-size: 18px; line-height: 1; }

@media (min-width: 1024px) {
  .dock { display: none; }
}

/* ---------- 11. Layout helpers ---------- */
.wrap {
  width: 100%;
  max-width: var(--maxw);
  margin-left: 0;
  margin-right: auto;
  padding-left: var(--pad);
  padding-right: var(--pad);
}

.wrap--narrow { max-width: 680px; }
.wrap--full { max-width: 100%; }

.section { padding-top: 56px; padding-bottom: 56px; }
.section--tight { padding-top: 32px; padding-bottom: 32px; }

@media (min-width: 1024px) {
  .section { padding-top: 88px; padding-bottom: 88px; }
  .section--tight { padding-top: 40px; padding-bottom: 40px; }
}

.band { background: var(--ink); }
.band--deep { background: var(--ink-2); }
.band--edge { background: var(--edge); }
.band--cream { background: var(--cream); color: var(--brown); }
.band--cream h1,
.band--cream h2,
.band--cream h3,
.band--cream h4 { color: var(--brown); }

.rule {
  height: 2px;
  background: repeating-linear-gradient(to right, var(--steel) 0 10px, transparent 10px 20px);
  opacity: .7;
}

/* ---------- 12. Frame / panel / breadcrumb ---------- */
.frame {
  position: relative;
  border: var(--line);
  background: var(--ink-2);
  padding: 28px;
}

.frame::before,
.frame::after { content: ""; position: absolute; background: var(--amber); }
.frame::before { left: -2px; top: -2px; width: 56px; height: 4px; }
.frame::after { right: -2px; bottom: -2px; width: 4px; height: 56px; }

.panel {
  position: relative;
  background: var(--ink-2);
  border: var(--line);
  box-shadow: var(--shadow);
  padding: 24px;
}

.panel--flat { box-shadow: none; }

.panel--paper {
  background: var(--cream);
  color: var(--brown);
}

.panel__label {
  display: inline-block;
  margin-bottom: 10px;
  font-family: var(--ff-label);
  font-size: 12px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--ember);
}

.panel__title { font-size: 20px; margin-bottom: 8px; }
.panel__text { font-size: 15px; line-height: 1.8; color: var(--mist); }
.panel--paper .panel__text { color: #4A3B32; }

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--ff-label);
  font-size: 12px;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--steel);
}

.breadcrumb a { color: var(--mist); transition: color .18s ease; }
.breadcrumb a:hover { color: var(--amber); }
.breadcrumb__sep { color: rgba(108, 135, 151, .6); }

/* ---------- 13. Grid ---------- */
.grid {
  display: grid;
  gap: 24px;
  grid-template-columns: 1fr;
}

@media (min-width: 720px) {
  .grid--2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 1024px) {
  .grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
}

@media (min-width: 900px) {
  .grid--stagger {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 28px 32px;
  }
  .grid--stagger > *:nth-child(even) { margin-top: 48px; }
  .grid--stagger > *:nth-child(4n + 3) { margin-top: 24px; }
}

/* ---------- 14. Media ---------- */
.media {
  position: relative;
  display: block;
  overflow: hidden;
  background: var(--ink-2);
  border: 2px solid var(--edge);
  box-shadow: var(--shadow);
  aspect-ratio: 16 / 10;
}

.media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(.78) contrast(1.05) brightness(.9);
}

.media::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: radial-gradient(120% 100% at 50% 35%, rgba(10, 26, 42, 0) 40%, rgba(5, 13, 21, .75) 100%);
}

.media--wide { aspect-ratio: 21 / 9; }
.media--portrait { aspect-ratio: 3 / 4; }
.media--square { aspect-ratio: 1 / 1; }
.media--bare { border: 0; box-shadow: none; }

.media__caption {
  margin-top: 10px;
  font-family: var(--ff-label);
  font-size: 12px;
  letter-spacing: .1em;
  color: var(--steel);
}

/* ---------- 15. Reveal ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity .2s ease-out, transform .2s ease-out;
}

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

/* ---------- 16. Footer ---------- */
.site-footer {
  position: relative;
  background: var(--ink);
  border-top: 2px solid var(--edge);
  margin-top: 64px;
}

.site-footer::before {
  content: "";
  display: block;
  height: 6px;
  background: linear-gradient(to right,
    var(--amber) 0 120px,
    var(--ember) 120px 180px,
    var(--ink-2) 180px 100%);
}

.footer__inner {
  width: 100%;
  max-width: var(--maxw);
  margin-left: 0;
  margin-right: auto;
  padding: 48px var(--pad) 36px;
  display: grid;
  gap: 36px;
}

@media (min-width: 900px) {
  .footer__inner {
    grid-template-columns: minmax(220px, 1fr) 2fr;
    gap: 56px;
    padding-top: 64px;
  }
}

.footer__brand-name {
  font-family: var(--ff-display);
  font-weight: 700;
  font-size: 28px;
  letter-spacing: .04em;
  color: var(--paper);
}

.footer__brand-en {
  margin-top: 6px;
  font-family: var(--ff-label);
  font-size: 11px;
  letter-spacing: .28em;
  text-transform: uppercase;
  color: var(--steel);
}

.footer__note {
  margin-top: 18px;
  padding-left: 14px;
  border-left: 3px solid var(--ember);
  font-size: 14px;
  line-height: 1.85;
  color: var(--mist);
}

.footer__cols {
  display: grid;
  gap: 28px;
}

@media (min-width: 600px) {
  .footer__cols { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}

.footer__title {
  font-family: var(--ff-label);
  font-size: 12px;
  font-weight: 400;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--steel);
  padding-bottom: 10px;
  margin-bottom: 8px;
  border-bottom: 1px solid rgba(108, 135, 151, .3);
}

.footer__list a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 15px;
  color: var(--paper);
  border-bottom: 1px solid transparent;
  transition: color .18s ease, border-color .18s ease;
}

.footer__list a:hover {
  color: var(--amber);
  border-bottom-color: var(--amber);
}

.footer__meta { border-top: 1px solid rgba(108, 135, 151, .28); }

.footer__meta-inner {
  width: 100%;
  max-width: var(--maxw);
  margin-left: 0;
  margin-right: auto;
  padding: 22px var(--pad) 44px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px 32px;
  font-family: var(--ff-label);
  font-size: 12px;
  letter-spacing: .08em;
  color: var(--steel);
}

.footer__contact { flex: 1 1 420px; line-height: 1.9; }

.footer__legal {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 18px;
}

.footer__icp,
.footer__copy { color: var(--steel); }

.footer__top {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 16px;
  border: 2px solid var(--steel);
  color: var(--mist);
  font-family: var(--ff-label);
  font-size: 12px;
  letter-spacing: .14em;
  text-transform: uppercase;
  transition: background-color .18s ease, border-color .18s ease, color .18s ease;
}

.footer__top:hover {
  background: var(--amber);
  border-color: var(--amber);
  color: var(--brown);
}

/* ---------- 17. Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: .001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .001ms !important;
    scroll-behavior: auto !important;
  }

  .read-progress { display: none; }
  .rail__marker { display: none; }

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