:root {
  --brand: #0b7a45;
  --brand-dark: #065c33;
  --brand-light: #e8f5ee;
  --accent: #b8860b;
  --accent-soft: #f4e8c8;
  --ink: #14201a;
  --muted: #4d5c54;
  --line: #d5e2da;
  --bg: #f4f7f5;
  --surface: #ffffff;
  --danger: #b42318;
  --radius: 12px;
  --shadow: 0 12px 40px rgba(6, 50, 28, 0.08);
  --max: 1120px;
  --font-display: "Source Han Serif SC", "Noto Serif SC", "Songti SC", serif;
  --font-body: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.75;
  font-size: 16px;
}

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

a {
  color: var(--brand-dark);
  text-decoration: none;
}

a:hover {
  color: var(--brand);
  text-decoration: underline;
}

.container {
  width: min(100% - 2rem, var(--max));
  margin-inline: auto;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 68px;
  gap: 1rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  color: var(--ink);
  text-decoration: none;
  font-weight: 700;
}

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

.logo img {
  width: 42px;
  height: 42px;
  border-radius: 8px;
  object-fit: cover;
}

.logo-text {
  font-family: var(--font-display);
  font-size: 1.15rem;
  letter-spacing: 0.02em;
}

.logo-text span {
  display: block;
  font-family: var(--font-body);
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--muted);
  letter-spacing: 0.04em;
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  cursor: pointer;
  padding: 0;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--ink);
  transition: 0.25s ease;
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.nav {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.nav a {
  padding: 0.55rem 0.75rem;
  color: var(--ink);
  font-weight: 500;
  font-size: 0.95rem;
  border-radius: 8px;
  text-decoration: none;
}

.nav a:hover,
.nav a.active {
  background: var(--brand-light);
  color: var(--brand-dark);
  text-decoration: none;
}

.nav-cta {
  display: flex;
  gap: 0.5rem;
  margin-left: 0.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.7rem 1.25rem;
  border-radius: 999px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: 0.2s ease;
  font-size: 0.95rem;
  font-family: inherit;
}

.btn:hover {
  text-decoration: none;
}

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

.btn-primary:hover {
  background: var(--brand-dark);
  color: #fff;
}

.btn-outline {
  background: transparent;
  color: var(--brand-dark);
  border: 1.5px solid var(--brand);
}

.btn-outline:hover {
  background: var(--brand-light);
  color: var(--brand-dark);
}

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

.btn-accent:hover {
  background: #9a7009;
  color: #fff;
}

.btn-lg {
  padding: 0.9rem 1.6rem;
  font-size: 1.05rem;
}

/* Hero */
.hero {
  position: relative;
  min-height: min(88vh, 720px);
  display: flex;
  align-items: flex-end;
  color: #fff;
  overflow: hidden;
  background: #0a3d24;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(120deg, rgba(4, 40, 22, 0.88) 0%, rgba(8, 70, 38, 0.55) 45%, rgba(4, 30, 18, 0.75) 100%),
    url("/开云体育首页.jpg") center / cover no-repeat;
}

.hero-bg::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse at 20% 80%, rgba(184, 134, 11, 0.18), transparent 50%),
    linear-gradient(to top, rgba(4, 30, 18, 0.55), transparent 40%);
}

.hero-content {
  position: relative;
  z-index: 1;
  padding: 4.5rem 0 3.5rem;
  width: min(100% - 2rem, var(--max));
  margin-inline: auto;
}

.hero-brand {
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 6vw, 3.8rem);
  font-weight: 700;
  line-height: 1.15;
  margin: 0 0 0.85rem;
  letter-spacing: 0.02em;
}

.hero-title {
  font-size: clamp(1.15rem, 2.5vw, 1.45rem);
  font-weight: 500;
  margin: 0 0 0.75rem;
  max-width: 36em;
  line-height: 1.5;
  opacity: 0.95;
}

.hero-desc {
  margin: 0 0 1.75rem;
  max-width: 34em;
  color: rgba(255, 255, 255, 0.88);
  font-size: 1.02rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
}

/* Sections */
.section {
  padding: 3.5rem 0;
}

.section-alt {
  background: var(--surface);
}

.section-head {
  margin-bottom: 2rem;
  max-width: 42rem;
}

.section-head h2 {
  font-family: var(--font-display);
  font-size: clamp(1.55rem, 3vw, 2rem);
  margin: 0 0 0.6rem;
  color: var(--ink);
  line-height: 1.3;
}

.section-head p {
  margin: 0;
  color: var(--muted);
  font-size: 1.02rem;
}

.prose {
  max-width: 48rem;
}

.prose h2,
.prose h3 {
  font-family: var(--font-display);
  line-height: 1.35;
  color: var(--ink);
}

.prose h2 {
  font-size: 1.55rem;
  margin: 2.2rem 0 0.85rem;
}

.prose h3 {
  font-size: 1.2rem;
  margin: 1.6rem 0 0.65rem;
}

.prose p {
  margin: 0 0 1rem;
  color: #24332b;
}

.prose ul,
.prose ol {
  margin: 0 0 1.1rem;
  padding-left: 1.35rem;
  color: #24332b;
}

.prose li {
  margin-bottom: 0.45rem;
}

.prose strong {
  color: var(--ink);
}

/* Feature grid */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
}

.feature-item {
  padding: 1.35rem 0;
  border-top: 2px solid var(--brand);
}

.feature-item h3 {
  margin: 0 0 0.5rem;
  font-size: 1.1rem;
  font-family: var(--font-display);
}

.feature-item p {
  margin: 0;
  color: var(--muted);
  font-size: 0.98rem;
}

/* Category strip */
.cat-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
}

.cat-link {
  position: relative;
  display: block;
  min-height: 140px;
  overflow: hidden;
  border-radius: var(--radius);
  color: #fff;
  text-decoration: none;
}

.cat-link:hover {
  text-decoration: none;
  color: #fff;
}

.cat-link img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.45s ease;
}

.cat-link:hover img {
  transform: scale(1.06);
}

.cat-link span {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: flex-end;
  padding: 1rem;
  background: linear-gradient(transparent 30%, rgba(0, 0, 0, 0.72));
  font-weight: 700;
  font-size: 1.05rem;
  font-family: var(--font-display);
}

/* Download / steps */
.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  counter-reset: step;
}

.step {
  position: relative;
  padding-left: 3.2rem;
}

.step::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0;
  width: 2.4rem;
  height: 2.4rem;
  border-radius: 50%;
  background: var(--brand);
  color: #fff;
  display: grid;
  place-items: center;
  font-weight: 700;
}

.step h3 {
  margin: 0.2rem 0 0.45rem;
  font-size: 1.08rem;
}

.step p {
  margin: 0;
  color: var(--muted);
}

/* Partners */
.partner-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 1rem;
  align-items: center;
}

.partner-grid img {
  width: 100%;
  max-height: 64px;
  object-fit: contain;
  filter: grayscale(0.15);
  opacity: 0.9;
  background: var(--surface);
  padding: 0.65rem;
  border-radius: 8px;
  border: 1px solid var(--line);
}

/* Promo gallery */
.promo-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
}

.promo-grid img {
  width: 100%;
  border-radius: var(--radius);
  border: 1px solid var(--line);
}

/* FAQ */
.faq-list {
  display: grid;
  gap: 0.75rem;
  max-width: 48rem;
}

.faq-item {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.faq-item summary {
  padding: 1rem 1.15rem;
  cursor: pointer;
  font-weight: 600;
  list-style: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: "+";
  float: right;
  color: var(--brand);
  font-weight: 700;
}

.faq-item[open] summary::after {
  content: "−";
}

.faq-item p {
  margin: 0;
  padding: 0 1.15rem 1.1rem;
  color: var(--muted);
}

/* Auth */
.auth-wrap {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  align-items: start;
  padding: 2.5rem 0 3.5rem;
}

.auth-panel {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.75rem;
  box-shadow: var(--shadow);
}

.auth-panel h1 {
  font-family: var(--font-display);
  font-size: 1.65rem;
  margin: 0 0 0.5rem;
}

.auth-panel .lead {
  color: var(--muted);
  margin: 0 0 1.35rem;
}

.form-group {
  margin-bottom: 1rem;
}

.form-group label {
  display: block;
  margin-bottom: 0.35rem;
  font-weight: 600;
  font-size: 0.92rem;
}

.form-group input {
  width: 100%;
  padding: 0.8rem 0.95rem;
  border: 1px solid var(--line);
  border-radius: 8px;
  font-size: 1rem;
  font-family: inherit;
  background: #fff;
}

.form-group input:focus {
  outline: 2px solid rgba(11, 122, 69, 0.25);
  border-color: var(--brand);
}

.form-hint {
  margin-top: 1rem;
  font-size: 0.92rem;
  color: var(--muted);
}

.auth-seo h2 {
  font-family: var(--font-display);
  font-size: 1.35rem;
  margin: 0 0 0.85rem;
}

.auth-seo h3 {
  font-size: 1.05rem;
  margin: 1.4rem 0 0.5rem;
}

.auth-seo p,
.auth-seo li {
  color: #24332b;
}

.page-hero {
  padding: 2.5rem 0 1.5rem;
  background:
    linear-gradient(135deg, #e8f5ee 0%, #f7f4ea 55%, #f4f7f5 100%);
  border-bottom: 1px solid var(--line);
}

.page-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(1.7rem, 3.5vw, 2.3rem);
  margin: 0 0 0.55rem;
}

.page-hero p {
  margin: 0;
  color: var(--muted);
  max-width: 40rem;
}

.breadcrumb {
  font-size: 0.88rem;
  color: var(--muted);
  margin-bottom: 0.85rem;
}

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

/* Error pages */
.error-page {
  min-height: 70vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 3rem 1rem;
}

.error-page .code {
  font-family: var(--font-display);
  font-size: clamp(4rem, 12vw, 7rem);
  line-height: 1;
  color: var(--brand);
  margin: 0;
}

.error-page h1 {
  margin: 0.5rem 0 0.75rem;
  font-size: 1.6rem;
}

.error-page p {
  color: var(--muted);
  max-width: 28rem;
  margin: 0 auto 1.5rem;
}

/* Footer */
.site-footer {
  background: #0d2a1b;
  color: rgba(255, 255, 255, 0.82);
  padding: 3rem 0 1.5rem;
  margin-top: 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 2rem;
  margin-bottom: 2rem;
}

.site-footer h3 {
  color: #fff;
  font-size: 1rem;
  margin: 0 0 0.85rem;
  font-family: var(--font-display);
}

.site-footer p {
  margin: 0 0 0.75rem;
  font-size: 0.95rem;
  line-height: 1.7;
}

.site-footer a {
  color: rgba(255, 255, 255, 0.82);
}

.site-footer a:hover {
  color: #fff;
}

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

.footer-links li {
  margin-bottom: 0.45rem;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding-top: 1.25rem;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.75rem;
  font-size: 0.88rem;
  color: rgba(255, 255, 255, 0.65);
}

/* Motion */
@media (prefers-reduced-motion: no-preference) {
  .hero-content {
    animation: rise 0.8s ease both;
  }

  .feature-item,
  .cat-link,
  .step {
    animation: rise 0.7s ease both;
  }

  .feature-item:nth-child(2),
  .cat-link:nth-child(2),
  .step:nth-child(2) {
    animation-delay: 0.08s;
  }

  .feature-item:nth-child(3),
  .cat-link:nth-child(3),
  .step:nth-child(3) {
    animation-delay: 0.16s;
  }

  .cat-link:nth-child(4) {
    animation-delay: 0.24s;
  }
}

@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(18px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Responsive */
@media (max-width: 960px) {
  .feature-grid,
  .steps,
  .promo-grid,
  .auth-wrap {
    grid-template-columns: 1fr;
  }

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

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

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

@media (max-width: 768px) {
  .nav-toggle {
    display: inline-flex;
  }

  .nav {
    position: fixed;
    inset: 68px 0 auto 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    background: #fff;
    border-bottom: 1px solid var(--line);
    padding: 0.75rem;
    box-shadow: var(--shadow);
    max-height: calc(100vh - 68px);
    overflow-y: auto;
  }

  .nav.is-open {
    display: flex;
  }

  .nav a {
    padding: 0.85rem 1rem;
  }

  .nav-cta {
    margin: 0.5rem 0 0;
    flex-direction: column;
  }

  .nav-cta .btn {
    width: 100%;
  }

  .hero {
    min-height: 72vh;
  }

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

@media (max-width: 480px) {
  .cat-grid,
  .partner-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}