:root {
  --brand: #ff201b;
  --brand-dark: #d91a16;
  --brand-soft: #fff1f0;
  --ink: #1a1a1a;
  --muted: #5c6370;
  --line: #ebebeb;
  --bg: #f7f8fa;
  --white: #ffffff;
  --shadow: 0 12px 40px rgba(26, 26, 26, 0.08);
  --radius: 16px;
  --max: 1180px;
  --font: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--white);
  line-height: 1.65;
}

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

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

.container {
  width: min(100% - 32px, var(--max));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(12px);
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 68px;
  gap: 20px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.15rem;
}

.logo-mark {
  width: 34px;
  height: 34px;
  border-radius: 8px;
  object-fit: contain;
  display: block;
  flex: 0 0 auto;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 22px;
  list-style: none;
  color: var(--muted);
  font-size: 0.95rem;
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--brand);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: none;
  border-radius: 999px;
  padding: 12px 24px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--brand);
  color: #fff;
  box-shadow: 0 8px 20px rgba(255, 32, 27, 0.28);
}

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

.btn-ghost {
  background: rgba(255, 255, 255, 0.18);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.35);
}

.btn-outline {
  background: transparent;
  color: var(--brand);
  border: 1px solid rgba(255, 32, 27, 0.35);
}

.hero {
  position: relative;
  overflow: hidden;
  color: #fff;
  background:
    radial-gradient(circle at 18% 20%, rgba(255, 255, 255, 0.18), transparent 28%),
    radial-gradient(circle at 85% 10%, rgba(255, 149, 35, 0.35), transparent 32%),
    linear-gradient(135deg, #ff201b 0%, #ff4f01 48%, #ff7a2e 100%);
  padding: 88px 0 96px;
}

.hero::after {
  content: "";
  position: absolute;
  inset: auto -10% -40% 40%;
  height: 420px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 50%;
  filter: blur(10px);
  animation: drift 10s ease-in-out infinite alternate;
}

@keyframes drift {
  from { transform: translateY(0); }
  to { transform: translateY(-24px); }
}

.hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 40px;
  align-items: center;
}

.hero h1 {
  font-size: clamp(2rem, 4vw, 3.2rem);
  line-height: 1.15;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
  animation: rise 0.7s ease both;
}

.hero p {
  font-size: 1.08rem;
  max-width: 34em;
  opacity: 0.94;
  margin-bottom: 28px;
  animation: rise 0.8s ease 0.08s both;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  animation: rise 0.85s ease 0.14s both;
}

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

.hero-panel {
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: 24px;
  padding: 28px;
  backdrop-filter: blur(8px);
  box-shadow: var(--shadow);
  animation: rise 0.9s ease 0.18s both;
}

.hero-panel h2 {
  font-size: 1.35rem;
  margin-bottom: 10px;
}

.hero-panel ul {
  list-style: none;
  display: grid;
  gap: 12px;
  margin-top: 18px;
}

.hero-panel li {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  font-size: 0.95rem;
}

.dot {
  width: 8px;
  height: 8px;
  margin-top: 8px;
  border-radius: 50%;
  background: #fff;
  flex: 0 0 auto;
}

.section {
  padding: 72px 0;
}

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

.section-head {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 40px;
}

.section-head h2 {
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  margin-bottom: 12px;
}

.section-head p {
  color: var(--muted);
}

.feature-grid,
.card-grid,
.platform-grid,
.article-grid {
  display: grid;
  gap: 20px;
}

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

.feature {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 24px;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

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

.feature-icon {
  width: 46px;
  height: 46px;
  border-radius: 12px;
  background: var(--brand-soft);
  color: var(--brand);
  display: grid;
  place-items: center;
  font-weight: 800;
  margin-bottom: 16px;
}

.feature h3 {
  margin-bottom: 8px;
  font-size: 1.15rem;
}

.feature p {
  color: var(--muted);
  font-size: 0.96rem;
}

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 36px;
  align-items: center;
}

.split-visual {
  min-height: 280px;
  border-radius: 24px;
  background:
    linear-gradient(160deg, rgba(255, 32, 27, 0.12), rgba(255, 149, 35, 0.18)),
    repeating-linear-gradient(-45deg, transparent, transparent 12px, rgba(255, 32, 27, 0.04) 12px, rgba(255, 32, 27, 0.04) 24px);
  border: 1px solid var(--line);
  display: grid;
  place-items: center;
  padding: 28px;
}

.visual-stack {
  width: min(100%, 360px);
  display: grid;
  gap: 12px;
}

.visual-row {
  background: #fff;
  border-radius: 12px;
  padding: 14px 16px;
  box-shadow: var(--shadow);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.92rem;
}

.badge {
  display: inline-block;
  background: var(--brand-soft);
  color: var(--brand);
  border-radius: 999px;
  padding: 4px 10px;
  font-size: 0.78rem;
  font-weight: 700;
}

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

.platform {
  text-align: center;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 16px;
}

.platform strong {
  display: block;
  margin: 10px 0 6px;
}

.platform p {
  color: var(--muted);
  font-size: 0.9rem;
}

.cta-band {
  margin: 20px 0 80px;
  border-radius: 28px;
  padding: 48px 32px;
  color: #fff;
  background: linear-gradient(120deg, #1a1a1a, #3a201c 55%, #ff201b);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.cta-band h2 {
  font-size: 1.7rem;
  margin-bottom: 8px;
}

.cta-band p {
  opacity: 0.9;
}

.site-footer {
  background: #151515;
  color: rgba(255, 255, 255, 0.78);
  padding: 48px 0 28px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 24px;
  margin-bottom: 28px;
}

.site-footer h3,
.site-footer h4 {
  color: #fff;
  margin-bottom: 12px;
}

.site-footer ul {
  list-style: none;
  display: grid;
  gap: 8px;
  font-size: 0.92rem;
}

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

.copyright {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 18px;
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.55);
}

.page-hero {
  padding: 56px 0 36px;
  background: linear-gradient(180deg, var(--brand-soft), #fff 80%);
}

.page-hero h1 {
  font-size: clamp(1.8rem, 3vw, 2.5rem);
  margin: 10px 0 12px;
}

.page-hero p {
  color: var(--muted);
  max-width: 46em;
}

.breadcrumb {
  color: var(--muted);
  font-size: 0.9rem;
}

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

.download-table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.download-table th,
.download-table td {
  padding: 16px 18px;
  text-align: left;
  border-bottom: 1px solid var(--line);
}

.download-table th {
  background: #fafafa;
  font-size: 0.92rem;
}

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

.article-card {
  display: flex;
  flex-direction: column;
  gap: 12px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
  min-height: 220px;
  transition: box-shadow 0.25s ease, transform 0.25s ease;
}

.article-card:hover {
  box-shadow: var(--shadow);
  transform: translateY(-3px);
}

.article-card .meta {
  color: var(--muted);
  font-size: 0.85rem;
}

.article-card h3 {
  font-size: 1.15rem;
  line-height: 1.4;
}

.article-card p {
  color: var(--muted);
  flex: 1;
}

.article-body {
  max-width: 780px;
  margin: 0 auto;
  padding: 20px 0 80px;
}

.article-body h2 {
  margin: 28px 0 12px;
  font-size: 1.35rem;
}

.article-body p,
.article-body li {
  color: #333;
  margin-bottom: 14px;
}

.article-body ul {
  padding-left: 1.2em;
  margin-bottom: 18px;
}

.article-update {
  margin: 18px 0 28px;
  padding: 14px 16px;
  border-left: 3px solid var(--brand);
  background: var(--brand-soft);
  border-radius: 0 10px 10px 0;
  color: #5a2a27;
  font-size: 0.94rem;
}

.menu-toggle {
  display: none;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 10px;
  width: 42px;
  height: 42px;
}

@media (max-width: 960px) {
  .hero-grid,
  .split,
  .feature-grid,
  .platform-grid,
  .article-grid,
  .footer-grid {
    grid-template-columns: 1fr;
  }

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

  .nav-links {
    display: none;
  }

  .menu-toggle {
    display: inline-grid;
    place-items: center;
  }

  .nav.open .nav-links {
    display: flex;
    position: absolute;
    left: 16px;
    right: 16px;
    top: 68px;
    flex-direction: column;
    align-items: flex-start;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 16px;
    box-shadow: var(--shadow);
  }
}

@media (max-width: 640px) {
  .platform-grid {
    grid-template-columns: 1fr;
  }

  .download-table th:nth-child(3),
  .download-table td:nth-child(3) {
    display: none;
  }
}