:root {
  --bg-deep: #0A1F3C;
  --bg-panel: #102A4C;
  --bg-sunken: #0D2438;
  --accent: #FF6B35;
  --accent-blue: #00D4FF;
  --text: #F5F0EB;
  --text-dim: #A0AAB5;
  --line: rgba(255,255,255,0.12);
  --line-strong: rgba(0,212,255,0.4);
  --font-display: Impact, "Arial Narrow Bold", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  --font-body: "Noto Sans SC", "Inter", -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
  --header-h: 68px;
  --content-max: 1240px;
  --gutter: clamp(16px, 4vw, 44px);
  --radius: 12px;
  --shadow-panel: 0 20px 50px rgba(1, 6, 16, 0.45);
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

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

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

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg-deep);
  -webkit-font-smoothing: antialiased;
}

ul, ol { list-style: none; }

a {
  color: var(--accent-blue);
  text-decoration: none;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease), background 0.2s var(--ease);
}

a:hover {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 4px;
}

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

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

::selection {
  background: rgba(0, 212, 255, 0.25);
  color: var(--text);
}

:focus-visible {
  outline: 2px solid var(--accent-blue);
  outline-offset: 3px;
  border-radius: 4px;
}

#main-content {
  outline: none;
  scroll-margin-top: calc(var(--header-h) + 12px);
}

@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;
  }
}

/* ---------- Skip link ---------- */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 1200;
  padding: 10px 18px;
  background: var(--accent);
  color: #fff;
  font-size: 14px;
  font-weight: 700;
  border-radius: 6px;
  transform: translateY(-160%);
  transition: transform 0.2s var(--ease);
}

.skip-link:focus {
  transform: none;
  color: #fff;
  text-decoration: none;
}

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(10, 31, 60, 0.84);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}

.site-header__band {
  height: 3px;
  background: repeating-linear-gradient(90deg, var(--accent) 0 16px, var(--accent-blue) 16px 34px, transparent 34px 70px);
  opacity: 0.9;
}

.site-header__bar {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 var(--gutter);
  height: var(--header-h);
  display: flex;
  align-items: center;
  gap: 18px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--text);
  text-decoration: none;
  flex-shrink: 0;
}

.brand:hover {
  color: var(--text);
  text-decoration: none;
}

.brand__mark {
  position: relative;
  display: block;
  width: 34px;
  height: 34px;
  flex-shrink: 0;
  border: 1px solid var(--accent);
  border-radius: 9px;
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent) 48%, transparent 52%);
  box-shadow: inset 0 0 0 1px rgba(0, 212, 255, 0.3);
}

.brand__mark::before {
  content: "";
  position: absolute;
  left: 7px;
  right: 7px;
  bottom: 6px;
  height: 3px;
  background: var(--accent-blue);
}

.brand__mark::after {
  content: "";
  position: absolute;
  left: 7px;
  right: 7px;
  bottom: 13px;
  height: 3px;
  background: var(--accent-blue);
  opacity: 0.75;
}

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

.brand__name {
  font-family: var(--font-display);
  font-size: 22px;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  font-weight: 700;
}

.brand__dot {
  color: var(--accent);
}

.brand__desc {
  font-size: 11px;
  color: var(--text-dim);
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.site-nav {
  margin-left: auto;
}

.site-nav__list {
  display: flex;
  gap: 2px;
  counter-reset: nav-index;
}

.site-nav__item {
  counter-increment: nav-index;
}

.site-nav__link {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  padding: 8px 10px;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-dim);
  border-bottom: 2px solid transparent;
  text-decoration: none;
  transition: color 0.2s var(--ease), border-color 0.2s var(--ease), background 0.2s var(--ease);
}

.site-nav__link::before {
  content: counter(nav-index, decimal-leading-zero);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--accent-blue);
  opacity: 0.7;
}

.site-nav__link:hover {
  color: var(--text);
  border-bottom-color: var(--accent);
  background: rgba(255, 107, 53, 0.08);
  text-decoration: none;
}

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

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

.header-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  font-size: 13px;
  font-weight: 600;
  color: var(--text);
  background: rgba(0, 212, 255, 0.06);
  text-decoration: none;
  flex-shrink: 0;
  transition: border-color 0.2s var(--ease), background 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.header-cta:hover {
  border-color: var(--accent-blue);
  background: rgba(0, 212, 255, 0.14);
  color: var(--text);
  text-decoration: none;
  box-shadow: 0 0 0 3px rgba(0, 212, 255, 0.15);
}

.header-cta__key {
  color: var(--accent-blue);
  border: 1px solid var(--line);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 11px;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 8px 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  flex-shrink: 0;
  transition: border-color 0.2s var(--ease);
}

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

.nav-toggle__box {
  position: relative;
  width: 20px;
  height: 14px;
}

.nav-toggle__bar {
  position: absolute;
  left: 0;
  height: 2px;
  width: 20px;
  background: var(--text);
  transition: transform 0.25s var(--ease), top 0.25s var(--ease);
}

.nav-toggle__bar--one { top: 2px; }
.nav-toggle__bar--two { top: 10px; }

.nav-toggle__label {
  font-size: 11px;
  color: var(--text-dim);
}

.site-header[data-open="true"] .nav-toggle__bar--one {
  top: 6px;
  transform: rotate(45deg);
}

.site-header[data-open="true"] .nav-toggle__bar--two {
  top: 6px;
  transform: rotate(-45deg);
}

@media (max-width: 1100px) {
  .header-cta__key { display: none; }
}

@media (max-width: 920px) {
  :root { --header-h: 60px; }

  .site-header__bar { gap: 10px; }

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

  .header-cta { display: none; }

  .site-nav {
    position: absolute;
    left: var(--gutter);
    right: var(--gutter);
    top: calc(100% + 6px);
    display: none;
    background: rgba(13, 36, 56, 0.97);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 12px;
    box-shadow: var(--shadow-panel);
  }

  .site-header[data-open="true"] .site-nav {
    display: block;
  }

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

  .site-nav__link {
    display: flex;
    align-items: center;
    justify-content: flex-start;
    gap: 10px;
    padding: 12px 10px;
    border-bottom: 1px solid var(--line);
    border-radius: 6px;
    font-size: 15px;
  }

  .site-nav__item:last-child .site-nav__link {
    border-bottom: none;
  }

  .site-nav__link:hover {
    border-bottom-color: transparent;
    background: rgba(0, 212, 255, 0.08);
  }

  .site-nav__link[aria-current="page"] {
    background: rgba(255, 107, 53, 0.1);
    border-bottom-color: transparent;
  }
}

@media (max-width: 520px) {
  .brand__desc { display: none; }
  .brand__name { font-size: 20px; }
  .brand__mark { width: 30px; height: 30px; }
}

/* ---------- Footer ---------- */
.site-footer {
  position: relative;
  margin-top: 80px;
  background:
    radial-gradient(60% 120% at 85% 0%, rgba(0, 212, 255, 0.08), transparent 60%),
    linear-gradient(180deg, var(--bg-sunken) 0%, var(--bg-deep) 32%);
  border-top: 1px solid var(--line);
  overflow: hidden;
}

.site-footer::before {
  content: "B-SPORTS // DATA LIVE";
  position: absolute;
  left: -2%;
  right: -2%;
  bottom: -3%;
  font-family: var(--font-display);
  font-size: clamp(44px, 9vw, 122px);
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 1px rgba(255, 255, 255, 0.05);
  letter-spacing: 0.05em;
  white-space: nowrap;
  text-align: center;
  pointer-events: none;
  user-select: none;
}

.site-footer__main,
.site-footer__bottom {
  position: relative;
  z-index: 1;
}

.site-footer__signal {
  position: relative;
  height: 3px;
  background: repeating-linear-gradient(90deg, var(--accent) 0 12px, transparent 12px 30px, var(--accent-blue) 30px 44px, transparent 44px 64px);
  opacity: 0.75;
}

.site-footer__signal-text {
  position: absolute;
  top: 14px;
  right: var(--gutter);
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--text-dim);
}

.site-footer__signal-text::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 0 rgba(255, 107, 53, 0.5);
}

.site-footer__main {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 60px var(--gutter) 44px;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 40px;
}

.site-footer__logo {
  font-family: var(--font-display);
  font-size: 34px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--text);
  margin-bottom: 14px;
}

.site-footer__logo-dot {
  color: var(--accent);
}

.site-footer__statement {
  font-size: 14px;
  color: var(--text-dim);
  max-width: 36em;
  margin-bottom: 20px;
}

.site-footer__line {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.site-footer__line span {
  font-size: 12px;
  line-height: 1.4;
  padding: 4px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--accent-blue);
  background: rgba(0, 212, 255, 0.05);
}

.site-footer__title {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text);
  margin-bottom: 14px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
}

.site-footer__title::before {
  content: "";
  width: 14px;
  height: 3px;
  background: var(--accent);
  flex-shrink: 0;
}

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

.site-footer__link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 14px;
  color: var(--text-dim);
  text-decoration: none;
  transition: color 0.2s var(--ease), transform 0.2s var(--ease);
}

.site-footer__link::before {
  content: "→";
  font-size: 12px;
  color: var(--accent-blue);
  opacity: 0;
  transform: translateX(-6px);
  transition: opacity 0.2s var(--ease), transform 0.2s var(--ease);
}

.site-footer__link:hover {
  color: var(--text);
  transform: translateX(4px);
  text-decoration: none;
}

.site-footer__link:hover::before {
  opacity: 1;
  transform: none;
}

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

.site-footer__contact-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 13px;
  color: var(--text-dim);
  line-height: 1.5;
  word-break: break-all;
}

.site-footer__contact-tag {
  margin-top: 2px;
  flex-shrink: 0;
  font-size: 11px;
  font-weight: 700;
  color: var(--accent);
  border: 1px solid rgba(255, 107, 53, 0.35);
  border-radius: 4px;
  padding: 1px 6px;
}

.site-footer__bottom {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 18px var(--gutter) 28px;
  border-top: 1px solid var(--line);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 28px;
  font-size: 13px;
  color: var(--text-dim);
}

.site-footer__copy {
  margin-right: auto;
}

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

.site-footer__legal span {
  color: var(--line-strong);
}

.site-footer__legal .site-footer__link::before {
  content: none;
}

.site-footer__icp {
  font-size: 12px;
  letter-spacing: 0.06em;
}

@media (max-width: 960px) {
  .site-footer__main {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }

  .site-footer__brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 560px) {
  .site-footer__main {
    grid-template-columns: 1fr;
    padding-top: 44px;
  }

  .site-footer__bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

  .site-footer__copy {
    margin-right: 0;
  }
}

/* ---------- Back to top ---------- */
.back-top {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 500;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  background: var(--bg-panel);
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  color: var(--text);
  font-size: 13px;
  font-weight: 600;
  box-shadow: var(--shadow-panel);
  opacity: 0;
  transform: translateY(12px);
  pointer-events: none;
  transition: opacity 0.3s var(--ease), transform 0.3s var(--ease), border-color 0.2s var(--ease);
}

.back-top[data-visible] {
  opacity: 1;
  transform: none;
  pointer-events: auto;
}

.back-top:hover {
  border-color: var(--accent);
  color: var(--text);
}

@media (max-width: 520px) {
  .back-top {
    right: 14px;
    bottom: 14px;
  }

  .back-top__text {
    display: none;
  }
}

/* ---------- Shared layout ---------- */
.container {
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 var(--gutter);
  width: 100%;
}

.page-frame {
  max-width: 1160px;
  margin: 0 auto;
  padding: clamp(28px, 5vw, 64px) var(--gutter);
  width: 100%;
}

.section {
  margin-bottom: clamp(48px, 8vw, 88px);
}

.section-head {
  display: flex;
  align-items: flex-end;
  flex-wrap: wrap;
  gap: 8px 16px;
  margin-bottom: 24px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line);
}

.section-index {
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--accent);
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(26px, 4vw, 40px);
  line-height: 1.05;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--text);
}

.section-subtitle {
  margin-left: auto;
  max-width: 26em;
  text-align: right;
  font-size: 14px;
  color: var(--text-dim);
}

@media (max-width: 640px) {
  .section-subtitle {
    margin-left: 0;
    text-align: left;
  }
}

.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 12px 0 20px;
  font-size: 13px;
  color: var(--text-dim);
}

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

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

.breadcrumbs span {
  opacity: 0.6;
}

/* ---------- Components ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 700;
  line-height: 1;
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: background 0.2s var(--ease), border-color 0.2s var(--ease), transform 0.2s var(--ease), box-shadow 0.2s var(--ease);
}

.btn--primary {
  background: var(--accent);
  color: #fff;
}

.btn--primary:hover {
  background: #ff7f4f;
  color: #fff;
  transform: translateY(-1px);
  box-shadow: 0 10px 24px rgba(255, 107, 53, 0.25);
  text-decoration: none;
}

.btn--ghost {
  border-color: var(--line-strong);
  color: var(--accent-blue);
  background: transparent;
}

.btn--ghost:hover {
  background: rgba(0, 212, 255, 0.1);
  border-color: var(--accent-blue);
  color: var(--accent-blue);
  text-decoration: none;
}

.prose {
  max-width: 68ch;
}

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

.prose h2 {
  font-family: var(--font-display);
  font-size: 24px;
  font-weight: 700;
  margin: 2em 0 0.8em;
}

.prose a {
  color: var(--accent-blue);
  text-decoration: underline;
  text-underline-offset: 4px;
}

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

.glass-card {
  background: rgba(16, 42, 76, 0.55);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(20px, 3vw, 32px);
  box-shadow: var(--shadow-panel);
}

.panel {
  background: var(--bg-panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(18px, 3vw, 28px);
}

.panel--sunken {
  background: var(--bg-sunken);
}

.diag-split {
  position: relative;
  overflow: hidden;
}

.diag-split::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 26%;
  height: 100%;
  background: linear-gradient(135deg, transparent 48%, rgba(0, 212, 255, 0.08) 48% 52%, transparent 52%);
  pointer-events: none;
}

.data-line {
  height: 1px;
  border: none;
  margin: 24px 0;
  background: repeating-linear-gradient(90deg, var(--accent-blue) 0 6px, transparent 6px 16px);
  opacity: 0.5;
}

.stat {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 18px 20px;
  background: rgba(16, 42, 76, 0.5);
  border-left: 3px solid var(--accent);
  border-radius: 0 10px 10px 0;
}

.stat__value {
  font-family: var(--font-display);
  font-size: clamp(30px, 4vw, 46px);
  font-weight: 700;
  line-height: 1;
  color: var(--text);
  font-variant-numeric: tabular-nums;
}

.stat__value small {
  font-size: 0.5em;
  color: var(--accent-blue);
  margin-left: 4px;
}

.stat__label {
  font-size: 13px;
  color: var(--text-dim);
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 600;
  line-height: 1.5;
  color: var(--accent-blue);
  border: 1px solid var(--line-strong);
  background: rgba(0, 212, 255, 0.06);
}

.tag--accent {
  color: var(--accent);
  border-color: rgba(255, 107, 53, 0.4);
  background: rgba(255, 107, 53, 0.08);
}

.tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 20px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.tab-btn {
  padding: 8px 16px;
  border-radius: 8px;
  border: 1px solid transparent;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-dim);
  transition: background 0.2s var(--ease), color 0.2s var(--ease), border-color 0.2s var(--ease);
}

.tab-btn:hover {
  color: var(--text);
  background: rgba(255, 255, 255, 0.06);
}

.tab-btn[aria-selected="true"] {
  color: var(--accent);
  border-color: rgba(255, 107, 53, 0.4);
  background: rgba(255, 107, 53, 0.1);
}

[data-tabpanel] {
  display: none;
}

[data-tabpanel][data-open] {
  display: block;
}

@media (prefers-reduced-motion: no-preference) {
  [data-tabpanel] {
    animation: tabIn 0.3s var(--ease);
  }

  @keyframes tabIn {
    from {
      opacity: 0;
      transform: translateY(8px);
    }
  }
}

/* ---------- Image frame ---------- */
.img-frame {
  position: relative;
  display: block;
  width: 100%;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    repeating-linear-gradient(135deg, rgba(255, 255, 255, 0.03) 0 10px, transparent 10px 20px),
    linear-gradient(180deg, var(--bg-panel), var(--bg-sunken));
}

.img-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.img-frame--ratio-16x9 { aspect-ratio: 16 / 9; }
.img-frame--ratio-4x3 { aspect-ratio: 4 / 3; }
.img-frame--ratio-1x1 { aspect-ratio: 1 / 1; }

.img-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(120deg, transparent 30%, rgba(0, 212, 255, 0.14) 48%, transparent 60%);
  opacity: 0;
  transition: opacity 0.3s var(--ease);
  pointer-events: none;
}

.img-frame:hover::after {
  opacity: 1;
}

/* ---------- Reveal ---------- */
.js [data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.6s var(--ease), transform 0.6s var(--ease);
  will-change: opacity, transform;
}

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

@media (prefers-reduced-motion: reduce) {
  .js [data-reveal],
  .js [data-reveal][data-in] {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }
}