/* ===== B体育竞技 · Site Kit 共享样式 /assets/site.css ===== */

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

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans CJK SC', 'Helvetica Neue', Arial, sans-serif;
  font-weight: 400;
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-navy);
  background: var(--color-ice);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

ul,
ol {
  list-style: none;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color 0.2s ease, background 0.2s ease, border-color 0.2s ease;
}

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

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: -apple-system, BlinkMacSystemFont, 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans CJK SC', sans-serif;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.25;
  color: var(--color-navy);
}

/* ---------- 2. Variables ---------- */
:root {
  --color-navy: #0B1E3A;
  --color-green: #00F0A8;
  --color-orange: #FF6A00;
  --color-ice: #E8F1FF;
  --color-panel: #112A4C;
  --color-midblue: #1C3E6B;
  --color-mist: #B7C9E2;
  --color-white: #FFFFFF;
  --color-charcoal: #0A1A2F;
  --color-warmyellow: #FFD166;

  --font-mono: 'SF Mono', SFMono-Regular, Consolas, 'Cascadia Mono', Menlo, monospace;
  --font-title: -apple-system, BlinkMacSystemFont, 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans CJK SC', sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans CJK SC', sans-serif;

  --container-width: 1280px;
  --container-pad: 24px;
  --header-h: 72px;
  --space-section: 96px;
  --space-section-mobile: 64px;
  --cut-angle: 2.5deg;
  --radius-chip: 4px 12px 4px 12px;
  --shadow-header: 0 2px 20px rgba(10, 26, 47, 0.3);
  --shadow-soft: 0 4px 24px rgba(11, 30, 58, 0.08);
  --shadow-card: 0 8px 32px rgba(11, 30, 58, 0.12);
  --transition-s: 0.2s ease;
  --transition-m: 0.3s ease;
}

/* ---------- 3. Base Typography ---------- */
p {
  line-height: 1.7;
}

em {
  font-style: italic;
}

strong {
  font-weight: 700;
  color: var(--color-navy);
}

.mono,
.data-number,
.scoreboard-prefix,
.scoreboard-count,
.footer-icp,
.brand-mark {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
}

::selection {
  background: var(--color-green);
  color: var(--color-navy);
}

/* ---------- 4. Layout Utilities ---------- */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--container-pad);
}

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

#main-content {
  display: block;
  scroll-margin-top: var(--header-h);
  min-height: 60vh;
}

.grid {
  display: grid;
  gap: 24px;
}

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

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

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

/* ---------- 5. Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  font-family: var(--font-title);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.01em;
  line-height: 1.4;
  border-radius: var(--radius-chip);
  border: 2px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: background var(--transition-s), color var(--transition-s), border-color var(--transition-s), transform var(--transition-s), box-shadow var(--transition-s);
  white-space: nowrap;
}

.btn-primary {
  background: var(--color-green);
  color: var(--color-navy);
}

.btn-primary:hover {
  background: #00d497;
  color: var(--color-navy);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0, 240, 168, 0.25);
}

.btn-ghost {
  background: transparent;
  color: var(--color-white);
  border-color: rgba(232, 241, 255, 0.4);
}

.btn-ghost:hover {
  border-color: var(--color-green);
  color: var(--color-green);
  background: rgba(0, 240, 168, 0.06);
}

.btn-orange {
  background: var(--color-orange);
  color: var(--color-white);
}

.btn-orange:hover {
  background: #ff8200;
  color: var(--color-white);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(255, 106, 0, 0.3);
}

/* ---------- 6. Header ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: transparent;
  border-bottom: 1px solid transparent;
  transition: background var(--transition-m), border-color var(--transition-m), box-shadow var(--transition-m);
}

.site-header[data-scrolled] {
  background: var(--color-navy);
  border-bottom-color: rgba(183, 201, 226, 0.15);
  box-shadow: var(--shadow-header);
}

.progress-bar {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--color-green);
  transform: scaleX(0);
  transform-origin: left center;
  z-index: 20;
  pointer-events: none;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  height: var(--header-h);
  position: relative;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--color-white);
  font-family: var(--font-title);
  font-weight: 800;
  font-size: 24px;
  letter-spacing: -0.02em;
  line-height: 1;
  z-index: 1;
  flex-shrink: 0;
}

.brand:hover .brand-mark {
  background: var(--color-warmyellow);
  color: var(--color-navy);
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: var(--color-green);
  color: var(--color-navy);
  font-weight: 700;
  font-size: 18px;
  line-height: 1;
  clip-path: polygon(6px 0, 100% 0, 100% calc(100% - 6px), calc(100% - 6px) 100%, 0 100%, 0 6px);
  transform: skewX(calc(var(--cut-angle) * -1));
  transition: background var(--transition-s), color var(--transition-s);
}

.brand-text {
  white-space: nowrap;
}

/* ---------- 7. Site Nav ---------- */
.site-nav {
  display: flex;
  align-items: center;
  gap: 24px;
  margin-left: auto;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.nav-item {
  margin: 0;
}

.nav-link {
  display: inline-block;
  padding: 8px 16px;
  color: rgba(232, 241, 255, 0.82);
  font-size: 15px;
  font-weight: 500;
  border-radius: var(--radius-chip);
  transition: color var(--transition-s), background var(--transition-s);
  white-space: nowrap;
}

.nav-link:hover {
  color: var(--color-white);
  background: rgba(255, 255, 255, 0.08);
}

.nav-link[aria-current="page"] {
  color: var(--color-green);
  font-weight: 700;
  background: rgba(0, 240, 168, 0.1);
}

.btn-subscribe {
  margin-left: 4px;
}

/* ---------- 8. Nav Toggle ---------- */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  color: var(--color-white);
  background: rgba(11, 30, 58, 0.4);
  border-radius: var(--radius-chip);
  border: 1px solid rgba(255, 255, 255, 0.2);
  z-index: 30;
  transition: background var(--transition-s), border-color var(--transition-s);
}

.nav-toggle:hover {
  background: rgba(11, 30, 58, 0.7);
  border-color: var(--color-green);
}

.nav-toggle-box {
  display: inline-flex;
  flex-direction: column;
  gap: 6px;
  width: 22px;
}

.nav-toggle-line {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--color-white);
  border-radius: 1px;
  transition: transform var(--transition-s), opacity var(--transition-s);
}

.nav-toggle[data-open] .nav-toggle-line:nth-child(1) {
  transform: translateY(4px) rotate(45deg);
}

.nav-toggle[data-open] .nav-toggle-line:nth-child(2) {
  transform: translateY(-4px) rotate(-45deg);
}

.nav-toggle-label {
  font-size: 14px;
  font-weight: 500;
}

/* ---------- 9. Skip Link ---------- */
.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 999;
  background: var(--color-green);
  color: var(--color-navy);
  font-weight: 700;
  font-size: 14px;
  padding: 10px 20px;
  border-radius: var(--radius-chip);
  transform: translateY(-200%);
  transition: transform var(--transition-s);
}

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

/* ---------- 10. Footer ---------- */
.site-footer {
  background: var(--color-charcoal);
  color: var(--color-mist);
  padding: 64px 0 0;
  position: relative;
}

.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--color-green) 0%, transparent 45%);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 48px;
  padding-bottom: 48px;
}

.footer-brand-col {
  max-width: 320px;
}

.brand-footer .brand-text {
  color: var(--color-white);
}

.footer-desc {
  margin-top: 16px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--color-mist);
}

.footer-title {
  font-family: var(--font-title);
  font-weight: 800;
  font-size: 14px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-white);
  margin-bottom: 20px;
  padding-bottom: 8px;
  position: relative;
}

.footer-title::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 24px;
  height: 2px;
  background: var(--color-green);
  border-radius: 1px;
}

.footer-links li,
.footer-contact li {
  margin-bottom: 10px;
}

.footer-links a,
.footer-contact a {
  color: var(--color-mist);
  font-size: 14px;
  transition: color var(--transition-s), padding-left var(--transition-s);
}

.footer-links a:hover,
.footer-contact a:hover {
  color: var(--color-green);
  padding-left: 4px;
}

.footer-contact li {
  font-size: 14px;
  color: var(--color-mist);
}

.footer-bottom {
  border-top: 1px solid rgba(183, 201, 226, 0.12);
  padding: 20px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

.footer-bottom p {
  font-size: 13px;
  color: rgba(183, 201, 226, 0.5);
}

.footer-icp {
  font-size: 13px;
  letter-spacing: 0.02em;
}

/* ---------- 11. Common Components ---------- */
.section-title {
  font-family: var(--font-title);
  font-weight: 800;
  font-size: 32px;
  letter-spacing: -0.02em;
  line-height: 1.2;
  color: var(--color-navy);
  margin-bottom: 16px;
}

.section-subtitle {
  font-size: 16px;
  color: var(--color-midblue);
  line-height: 1.7;
  max-width: 640px;
  margin-bottom: 32px;
}

.scoreboard-header {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: 24px;
}

.scoreboard-header .scoreboard-prefix,
.scoreboard-header .scoreboard-count {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 6px 14px;
  background: var(--color-navy);
  color: var(--color-green);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 15px;
  line-height: 1;
  border-radius: var(--radius-chip);
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.scoreboard-header .scoreboard-count {
  background: var(--color-green);
  color: var(--color-navy);
}

.scoreboard-header .scoreboard-label {
  font-family: var(--font-title);
  font-weight: 800;
  font-size: 28px;
  letter-spacing: -0.02em;
  line-height: 1.2;
  color: var(--color-navy);
  text-transform: none;
}

.chamfer-panel {
  position: relative;
  background: var(--color-panel);
  color: var(--color-ice);
  padding: 24px;
  clip-path: polygon(0 0, calc(100% - 20px) 0, 100% 20px, 100% 100%, 20px 100%, 0 calc(100% - 20px));
  transition: transform var(--transition-s), box-shadow var(--transition-s);
}

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

.chamfer-panel--light {
  background: var(--color-white);
  color: var(--color-navy);
  box-shadow: var(--shadow-soft);
}

.chamfer-panel--light:hover {
  box-shadow: var(--shadow-card);
}

.research-card {
  position: relative;
  background: var(--color-white);
  border-left: 4px solid var(--color-green);
  border-radius: 0 16px 0 16px;
  padding: 24px;
  box-shadow: var(--shadow-soft);
  transition: transform var(--transition-s), box-shadow var(--transition-s);
}

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

.research-card .card-summary {
  font-size: 15px;
  color: var(--color-midblue);
  line-height: 1.65;
}

.research-card .card-evidence {
  border-top: 1px solid rgba(11, 30, 58, 0.08);
  margin-top: 16px;
  padding-top: 16px;
  font-size: 13px;
  color: var(--color-mist);
  font-family: var(--font-mono);
  line-height: 1.6;
}

.research-card .card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 16px;
  gap: 12px;
  flex-wrap: wrap;
}

.term-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 14px;
  background: rgba(255, 209, 102, 0.1);
  border: 1px solid var(--color-warmyellow);
  color: var(--color-warmyellow);
  font-size: 13px;
  font-weight: 500;
  border-radius: 999px;
  letter-spacing: 0.02em;
  line-height: 1.5;
}

.term-tag--navy {
  background: rgba(11, 30, 58, 0.08);
  border-color: var(--color-mist);
  color: var(--color-midblue);
}

.data-number {
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--color-green);
  font-variant-numeric: tabular-nums;
}

.data-number--navy {
  color: var(--color-navy);
}

.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--color-mist);
  margin-bottom: 24px;
}

.breadcrumbs a {
  color: var(--color-midblue);
  transition: color var(--transition-s);
}

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

.breadcrumbs .crumb-separator {
  color: var(--color-mist);
  font-size: 12px;
}

.breadcrumbs .crumb-current {
  color: var(--color-navy);
  font-weight: 600;
}

.page-hero {
  background: var(--color-navy);
  color: var(--color-white);
  padding: calc(var(--header-h) + 64px) 0 56px;
  position: relative;
  overflow: hidden;
}

.page-hero::after {
  content: '';
  position: absolute;
  right: -15%;
  top: -20%;
  width: 50%;
  height: 70%;
  background: linear-gradient(135deg, transparent, rgba(0, 240, 168, 0.08));
  transform: skewX(calc(var(--cut-angle) * -1));
  pointer-events: none;
}

.page-hero .breadcrumbs a {
  color: var(--color-mist);
}

.page-hero .breadcrumbs a:hover {
  color: var(--color-green);
}

.page-hero .breadcrumbs .crumb-current {
  color: var(--color-white);
}

.image-container {
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, var(--color-midblue), var(--color-navy));
  aspect-ratio: 16 / 9;
  border-radius: 4px 16px 4px 16px;
}

.image-container::after {
  content: '';
  position: absolute;
  right: -20%;
  top: -20%;
  width: 60%;
  height: 65%;
  background: linear-gradient(135deg, transparent, rgba(0, 240, 168, 0.14));
  transform: skewX(calc(var(--cut-angle) * -1));
  pointer-events: none;
}

.image-container img,
.image-container .image-placeholder {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.image-container .image-placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(232, 241, 255, 0.45);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.04em;
}

/* ---------- 12. Focus & Reduced Motion ---------- */
a:focus-visible,
button:focus-visible,
[tabindex]:focus-visible,
summary:focus-visible {
  outline: 2px solid var(--color-green);
  outline-offset: 2px;
  border-radius: 4px;
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }

  .nav-toggle:hover,
  .btn:hover,
  .chamfer-panel:hover,
  .research-card:hover {
    transform: none;
  }
}

/* ---------- 13. Responsive ---------- */
@media (max-width: 1024px) {
  :root {
    --space-section: 80px;
  }

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

  .grid-3 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

@media (max-width: 960px) {
  :root {
    --header-h: 64px;
    --container-pad: 20px;
  }

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

  .site-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 25;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 16px;
    background: var(--color-navy);
    margin-left: 0;
    opacity: 0;
    visibility: hidden;
    transform: translateX(100%);
    transition: transform 0.35s ease, opacity 0.35s ease, visibility 0.35s;
    padding: var(--header-h) 32px 48px;
    overflow-y: auto;
  }

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

  .header-inner {
    position: relative;
    z-index: 40;
  }

  .nav-list {
    flex-direction: column;
    align-items: center;
    gap: 4px;
    width: 100%;
  }

  .nav-link {
    font-size: 22px;
    font-weight: 700;
    padding: 14px 28px;
    text-align: center;
    width: 100%;
    color: var(--color-ice);
  }

  .nav-link[aria-current="page"] {
    color: var(--color-green);
    background: rgba(0, 240, 168, 0.1);
  }

  .btn-subscribe {
    margin-top: 24px;
    margin-left: 0;
    font-size: 17px;
    padding: 14px 40px;
  }
}

@media (max-width: 768px) {
  :root {
    --space-section: 64px;
    --container-pad: 16px;
  }

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

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

  .footer-brand-col {
    max-width: none;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

  .scoreboard-header .scoreboard-label {
    font-size: 24px;
  }

  .scoreboard-header .scoreboard-prefix,
  .scoreboard-header .scoreboard-count {
    font-size: 13px;
    padding: 5px 10px;
  }

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

  .page-hero {
    padding: calc(var(--header-h) + 40px) 0 40px;
  }
}

@media (max-width: 480px) {
  .btn {
    width: 100%;
  }

  .btn-subscribe {
    width: auto;
    min-width: 200px;
  }

  .nav-toggle-label {
    display: none;
  }
}