/* =========================================================
   site.css — kaiyun·买球 全站共享样式
   bet-welcomekaiyun.com.cn · V4
   ========================================================= */

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

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

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg-dark);
  color: var(--silver);
  font-family: var(--body-font);
  font-size: 1rem;
  line-height: 1.7;
}

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

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

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

ul, ol {
  list-style: none;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--heading-font);
  line-height: 1.2;
  color: #fff;
  letter-spacing: 0.01em;
  margin-bottom: 0.75rem;
}

h1 {
  font-size: 3.2rem;
  text-shadow: 3px 3px 0 rgba(0, 229, 255, 0.22);
}

h2 {
  font-size: 2.4rem;
  text-shadow: 2px 2px 0 rgba(57, 255, 20, 0.16);
}

h3 { font-size: 1.8rem; }
h4 { font-size: 1.2rem; }

p { margin-bottom: 1rem; }

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

:focus-visible {
  outline: 3px solid var(--electric-blue);
  outline-offset: 2px;
}

/* ---------- Variables ---------- */
:root {
  --bg-dark: #0D1117;
  --bg-panel: #1C2A3A;
  --bg-paper: #F4E9D8;
  --neon-green: #39FF14;
  --electric-blue: #00E5FF;
  --gold: #FFC947;
  --silver: #E0E6ED;
  --warning-red: #FF4D4F;
  --green-glow: rgba(57, 255, 20, 0.15);
  --blue-glow: rgba(0, 229, 255, 0.12);
  --heading-font: "Arial Black", "Impact", "Noto Sans SC", sans-serif;
  --body-font: "Inter", "Noto Sans SC", "PingFang SC", sans-serif;
  --border-w: 3px;
  --shadow-hard: 8px 8px 0 rgba(0, 0, 0, 0.4);
  --shadow-sm: 4px 4px 0 rgba(0, 0, 0, 0.4);
  --container-w: 1280px;
}

/* ---------- Layout ---------- */
.main-content {
  flex: 1;
  width: 100%;
}

#main-content:focus {
  outline: none;
}

#main-content {
  scroll-margin-top: 8rem;
}

.container {
  width: 100%;
  max-width: var(--container-w);
  margin-inline: auto;
  padding-inline: 1.5rem;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.7rem 1.6rem;
  background: transparent;
  border: var(--border-w) solid var(--silver);
  color: var(--silver);
  font-family: var(--heading-font);
  font-size: 0.88rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease;
}

.btn:hover {
  transform: translate(-2px, -2px);
  box-shadow: 6px 6px 0 rgba(0, 0, 0, 0.5);
}

.btn-primary {
  background: var(--neon-green);
  border-color: var(--neon-green);
  color: #000;
}

.btn-primary:hover {
  background: transparent;
  color: var(--neon-green);
}

.btn-ghost {
  border-color: var(--electric-blue);
  color: var(--electric-blue);
}

.btn-ghost:hover {
  background: var(--electric-blue);
  color: #000;
}

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(13, 17, 23, 0.94);
  border-bottom: 1px solid rgba(224, 230, 237, 0.12);
}

.header-top {
  background: #0A0E13;
  border-bottom: 1px solid rgba(0, 229, 255, 0.22);
  font-size: 0.8rem;
}

.header-top-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-height: 38px;
}

.header-slogan {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0;
  color: var(--silver);
  font-size: 0.8rem;
  letter-spacing: 0.02em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.slogan-arrow {
  color: var(--electric-blue);
  font-family: var(--heading-font);
  font-weight: bold;
  font-size: 0.9rem;
  transform: skewX(-10deg);
}

.version-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  flex-shrink: 0;
  padding: 2px 10px;
  background: rgba(255, 201, 71, 0.1);
  border: 2px solid var(--gold);
  color: var(--gold);
  font-family: var(--heading-font);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  transform: rotate(2deg);
  transition: transform 0.25s ease, background-color 0.25s ease;
}

.version-badge:hover {
  transform: rotate(-2deg) scale(1.04);
  background: rgba(255, 201, 71, 0.22);
}

.header-bottom {
  background: rgba(28, 42, 58, 0.3);
  border-top: 1px solid rgba(57, 255, 20, 0.12);
}

.header-bottom-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  min-height: 72px;
}

/* Brand */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  flex-shrink: 0;
  text-decoration: none;
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  background: var(--neon-green);
  color: #000;
  font-family: var(--heading-font);
  font-size: 1.4rem;
  font-weight: bold;
  border: 2px solid #000;
  box-shadow: var(--shadow-sm);
  transform: skewX(-10deg);
  transition: transform 0.2s ease, background-color 0.2s ease;
}

.brand:hover .brand-mark {
  background: var(--electric-blue);
  transform: skewX(-10deg) scale(1.06);
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}

.brand-text strong {
  font-family: var(--heading-font);
  font-size: 1.05rem;
  color: #fff;
  letter-spacing: 0.02em;
  transition: color 0.2s ease;
}

.brand-text small {
  font-size: 0.72rem;
  color: var(--electric-blue);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  transition: color 0.2s ease;
}

.brand:hover .brand-text strong {
  color: var(--neon-green);
}

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

/* Nav */
.nav {
  display: block;
  flex-shrink: 0;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav-link {
  position: relative;
  display: block;
  padding: 0.6rem 0.8rem;
  color: var(--silver);
  font-weight: 600;
  font-size: 0.92rem;
  letter-spacing: 0.03em;
  white-space: nowrap;
  transition: color 0.2s ease, background-color 0.2s ease;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 3px;
  background: var(--neon-green);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.22s ease;
}

.nav-link:hover {
  color: var(--neon-green);
  background: var(--green-glow);
}

.nav-link:hover::after {
  transform: scaleX(1);
}

.nav-link[aria-current="page"] {
  color: var(--neon-green);
  background: var(--green-glow);
}

.nav-link[aria-current="page"]::after {
  transform: scaleX(1);
  background: var(--electric-blue);
}

/* Nav toggle */
.nav-toggle {
  display: none;
  position: relative;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: var(--neon-green);
  border: 2px solid #000;
  box-shadow: var(--shadow-sm);
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
  z-index: 1102;
  transition: background-color 0.2s ease, box-shadow 0.2s ease;
}

.nav-toggle:hover {
  background: var(--electric-blue);
  box-shadow: 6px 6px 0 rgba(0, 0, 0, 0.5);
}

.nav-toggle-bar {
  display: block;
  width: 22px;
  height: 3px;
  background: #000;
  transition: transform 0.25s ease, opacity 0.2s ease;
}

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

body.nav-open .nav-toggle {
  background: var(--electric-blue);
}

body.nav-open .nav-toggle-bar:nth-child(1) {
  transform: translateY(8px) rotate(45deg);
}

body.nav-open .nav-toggle-bar:nth-child(2) {
  opacity: 0;
}

body.nav-open .nav-toggle-bar:nth-child(3) {
  transform: translateY(-8px) rotate(-45deg);
}

/* Scroll progress */
.scroll-progress {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0%;
  height: 3px;
  background: linear-gradient(90deg, var(--electric-blue), var(--neon-green));
  z-index: 5;
  pointer-events: none;
}

/* Skip link */
.skip-link {
  position: absolute;
  top: -200px;
  left: 0;
  z-index: 3000;
  background: var(--neon-green);
  color: #000;
  font-weight: 700;
  font-family: var(--heading-font);
  font-size: 0.85rem;
  padding: 0.7rem 1.25rem;
  border: 2px solid #000;
  border-radius: 0 0 4px 0;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 0;
  color: #000;
}

/* ---------- Footer ---------- */
.site-footer {
  background:
    repeating-linear-gradient(135deg, rgba(255, 255, 255, 0.015) 0, rgba(255, 255, 255, 0.015) 1px, transparent 1px, transparent 12px),
    #0A0E13;
  color: var(--silver);
  border-top: var(--border-w) solid var(--electric-blue);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 2.5rem;
  padding: 3.5rem 0 2.5rem;
}

.footer-brand .brand-text strong {
  color: #fff;
}

.footer-desc {
  margin-top: 1rem;
  font-size: 0.88rem;
  line-height: 1.65;
  color: var(--silver);
  max-width: 34em;
}

.footer-trust {
  margin-top: 0.75rem;
  padding-left: 0.75rem;
  border-left: 3px solid var(--gold);
  color: var(--gold);
  font-size: 0.8rem;
  line-height: 1.6;
}

.footer-heading {
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--neon-green);
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  position: relative;
  text-shadow: none;
}

.footer-heading::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 32px;
  height: 3px;
  background: var(--electric-blue);
}

.footer-links ul,
.footer-contact ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.footer-links li {
  margin-bottom: 0.5rem;
}

.footer-links a {
  color: var(--silver);
  font-size: 0.88rem;
  transition: color 0.2s ease, padding-left 0.2s ease;
}

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

.footer-contact li {
  font-size: 0.88rem;
  margin-bottom: 0.5rem;
  line-height: 1.6;
}

.footer-contact li strong {
  color: var(--electric-blue);
  font-weight: 600;
}

.footer-note {
  margin-top: 1rem;
  padding-top: 0.75rem;
  border-top: 1px dashed rgba(224, 230, 237, 0.18);
  font-size: 0.78rem;
  color: rgba(224, 230, 237, 0.65);
}

.footer-bottom {
  border-top: 1px solid rgba(57, 255, 20, 0.22);
  padding: 1rem 0;
}

.footer-bottom-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem 1.5rem;
  font-size: 0.8rem;
}

.footer-copy {
  margin: 0;
  color: rgba(224, 230, 237, 0.62);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.footer-legal a {
  color: var(--silver);
  font-size: 0.8rem;
}

.footer-legal a:hover {
  color: var(--electric-blue);
}

/* ---------- Back to top ---------- */
.back-to-top {
  position: fixed;
  right: 1.5rem;
  bottom: 1.5rem;
  z-index: 1080;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 3px solid #000;
  background: var(--electric-blue);
  color: #000;
  font-size: 1.2rem;
  font-weight: bold;
  line-height: 1;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateY(12px);
  transition: opacity 0.22s ease, transform 0.22s ease, visibility 0.22s ease, background-color 0.2s ease;
}

.back-to-top[data-visible="true"] {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--neon-green);
}

/* ---------- Sections ---------- */
.section {
  padding: 4.5rem 0;
}

.section-sm {
  padding: 2.5rem 0;
}

.section-paper {
  background: var(--bg-paper);
  color: #1A1A1A;
}

.section-paper h1,
.section-paper h2,
.section-paper h3,
.section-paper h4,
.section-paper h5,
.section-paper h6 {
  color: #1A1A1A;
}

.section-paper a {
  color: #0B6E00;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.section-paper a:hover {
  color: #000;
}

.section-dark {
  background: #0A0E13;
}

.section-title {
  font-size: 2.4rem;
  line-height: 1.1;
  text-transform: uppercase;
  letter-spacing: 0.02em;
  margin-bottom: 1.6rem;
  padding-bottom: 0.6rem;
  border-bottom: 3px solid rgba(57, 255, 20, 0.3);
  display: flex;
  align-items: center;
  gap: 0.7rem;
}

.section-title::before {
  content: "//";
  color: var(--electric-blue);
  font-size: 0.9em;
  transform: skewX(-10deg);
}

/* ---------- Grid ---------- */
.grid {
  display: grid;
  gap: 1.5rem;
}

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

/* ---------- Panels & Cards ---------- */
.panel {
  background: var(--bg-panel);
  border: var(--border-w) solid #24344A;
  box-shadow: var(--shadow-hard);
  padding: 1.5rem;
}

.card {
  background: var(--bg-panel);
  border: var(--border-w) solid #24344A;
  box-shadow: var(--shadow-hard);
  padding: 1.5rem;
  transition: border-color 0.2s ease, box-shadow 0.2s ease, transform 0.2s ease;
}

.card:hover {
  border-color: var(--neon-green);
  box-shadow: 10px 10px 0 rgba(0, 0, 0, 0.5);
  transform: translate(-2px, -2px);
}

.card-blue { border-left: 4px solid var(--electric-blue); }
.card-green { border-top: 4px solid var(--neon-green); }
.card-gold { border-right: 4px solid var(--gold); }

/* ---------- Breadcrumb ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem;
  padding: 0.9rem 0;
  font-size: 0.82rem;
  color: rgba(224, 230, 237, 0.6);
}

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

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

.breadcrumb-sep {
  color: var(--electric-blue);
  margin: 0 0.15rem;
}

.breadcrumb [aria-current="page"] {
  color: var(--gold);
}

/* ---------- Data pairs ---------- */
.data-pair {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
}

.data-label {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--electric-blue);
}

.data-value {
  font-family: var(--heading-font);
  font-size: 1.6rem;
  line-height: 1.2;
  color: #fff;
  font-variant-numeric: tabular-nums;
}

.data-value.gold {
  color: var(--gold);
}

/* ---------- Image frames ---------- */
.img-frame {
  position: relative;
  overflow: hidden;
  background: var(--bg-panel);
  border: var(--border-w) solid #24344A;
  box-shadow: var(--shadow-hard);
  aspect-ratio: 16 / 9;
}

.img-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(1.12) contrast(1.05);
  transition: transform 0.3s ease;
}

.img-frame:hover img {
  transform: scale(1.04);
}

.img-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  border: 2px solid transparent;
  transition: border-color 0.25s ease;
  pointer-events: none;
}

.img-frame:hover::after {
  border-color: var(--electric-blue);
}

.img-frame-4-3 { aspect-ratio: 4 / 3; }
.img-frame-1-1 { aspect-ratio: 1 / 1; }

/* ---------- Page hero ---------- */
.page-hero {
  position: relative;
  padding: 3rem 0 2.8rem;
  border-bottom: var(--border-w) solid rgba(57, 255, 20, 0.2);
  overflow: hidden;
}

.page-hero h1 {
  font-size: 3.2rem;
  line-height: 1.05;
  text-transform: uppercase;
  transform: skewX(-2deg);
  margin-bottom: 0.75rem;
}

.page-hero-meta {
  max-width: 62ch;
  color: var(--silver);
  font-size: 1.05rem;
}

.hero-slashes {
  position: absolute;
  right: -0.05em;
  top: 0;
  font-family: var(--heading-font);
  font-size: 18rem;
  line-height: 1;
  color: transparent;
  -webkit-text-stroke: 2px rgba(0, 229, 255, 0.12);
  pointer-events: none;
  user-select: none;
}

/* ---------- Prose ---------- */
.prose p {
  margin-bottom: 1.1rem;
}

.prose strong {
  color: var(--neon-green);
  font-weight: 700;
}

.prose a {
  text-decoration: underline;
  text-underline-offset: 3px;
}

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

.mega-number {
  font-family: var(--heading-font);
  font-size: 5.5rem;
  line-height: 0.9;
  color: transparent;
  -webkit-text-stroke: 2px var(--electric-blue);
}

.slant-label {
  display: inline-block;
  transform: skewX(-10deg);
  background: var(--neon-green);
  color: #000;
  padding: 0.15rem 0.7rem;
  font-family: var(--heading-font);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

/* ---------- Responsive ---------- */
@media (max-width: 992px) {
  h1 { font-size: 2.6rem; }
  h2 { font-size: 2rem; }
  .section { padding: 3.2rem 0; }
  .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .page-hero h1 { font-size: 2.6rem; }
}

@media (max-width: 900px) {
  .header-top { display: none; }

  .header-bottom-inner {
    min-height: 60px;
  }

  .nav-toggle {
    display: inline-flex;
    position: fixed;
    right: 1.25rem;
    bottom: 1.25rem;
  }

  .nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    z-index: 1101;
    display: flex;
    align-items: center;
    justify-content: center;
    background:
      radial-gradient(circle at 15% 12%, rgba(57, 255, 20, 0.1) 0, transparent 42%),
      radial-gradient(circle at 85% 88%, rgba(0, 229, 255, 0.09) 0, transparent 38%),
      rgba(13, 17, 23, 0.97);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.28s ease, visibility 0.28s ease;
  }

  .nav[data-open="true"] {
    opacity: 1;
    visibility: visible;
  }

  .nav-list {
    flex-direction: column;
    gap: 0.4rem;
    align-items: center;
    text-align: center;
  }

  .nav-link {
    font-size: 1.5rem;
    font-family: var(--heading-font);
    text-transform: uppercase;
    padding: 0.6rem 1.5rem;
    transform: skewX(-4deg);
    border: 2px solid transparent;
    white-space: normal;
  }

  .nav-link:hover {
    transform: skewX(-4deg) translateX(6px);
    border-color: var(--neon-green);
  }

  body.nav-open {
    overflow: hidden;
  }

  .back-to-top {
    right: 1.25rem;
    bottom: 6rem;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 2.25rem;
    padding: 2.5rem 0 2rem;
  }
}

@media (max-width: 640px) {
  .container { padding-inline: 1.25rem; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .page-hero { padding: 2.2rem 0 2rem; }
  .page-hero h1 { font-size: 2rem; }
  .section-title { font-size: 1.7rem; }
  .footer-bottom-inner { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 480px) {
  .brand-text small { display: none; }
  .brand-mark { width: 36px; height: 36px; font-size: 1.1rem; }
  .brand-text strong { font-size: 0.95rem; }
}

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

  *, *::before, *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}