:root {
  --brand: #1a7fd4;
  --brand-dark: #0d5fa8;
  --brand-deep: #074a86;
  --ink: #142433;
  --muted: #5a6b7d;
  --line: #d7e3ef;
  --bg: #f3f8fc;
  --paper: #ffffff;
  --accent: #00a8a0;
  --warn: #c45c26;
  --radius: 14px;
  --shadow: 0 12px 40px rgba(13, 95, 168, 0.1);
  --max: 1120px;
  --font: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --display: "ZCOOL XiaoWei", "Noto Sans SC", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background:
    radial-gradient(1200px 500px at 10% -10%, rgba(26, 127, 212, 0.14), transparent 60%),
    radial-gradient(900px 420px at 100% 0%, rgba(0, 168, 160, 0.1), transparent 55%),
    linear-gradient(180deg, #eef6fb 0%, var(--bg) 32%, #eaf3f9 100%);
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

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;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(14px);
  background: rgba(255, 255, 255, 0.88);
  border-bottom: 1px solid rgba(215, 227, 239, 0.9);
}

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

.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  color: var(--ink);
  text-decoration: none;
  font-weight: 700;
  letter-spacing: 0.02em;
}

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

.brand img {
  width: 42px;
  height: 42px;
  border-radius: 10px;
  object-fit: cover;
}

.brand-name {
  font-family: var(--display);
  font-size: 1.25rem;
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem 1rem;
  align-items: center;
  justify-content: flex-end;
}

.nav-links a {
  color: var(--muted);
  font-size: 0.95rem;
  font-weight: 500;
}

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

.nav-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.45rem 0.95rem;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--brand), var(--accent));
  color: #fff !important;
  font-weight: 600;
  box-shadow: 0 8px 20px rgba(26, 127, 212, 0.28);
}

.nav-cta:hover {
  filter: brightness(1.05);
  text-decoration: none;
}

.menu-toggle {
  display: none;
  border: 1px solid var(--line);
  background: var(--paper);
  border-radius: 10px;
  padding: 0.45rem 0.7rem;
  color: var(--ink);
  cursor: pointer;
}

.hero {
  position: relative;
  overflow: hidden;
  padding: 3.2rem 0 2.4rem;
  background: linear-gradient(120deg, rgba(7, 74, 134, 0.96), rgba(26, 127, 212, 0.92) 48%, rgba(0, 140, 150, 0.9));
  color: #fff;
}

.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 40%, rgba(7, 48, 86, 0.35));
  pointer-events: none;
}

.hero .container {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 2rem;
  align-items: center;
}

.hero-copy h1 {
  margin: 0 0 0.85rem;
  font-family: var(--display);
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.25;
  font-weight: 400;
  text-shadow: 0 2px 18px rgba(0, 0, 0, 0.22);
}

.hero-copy p {
  margin: 0 0 1.4rem;
  max-width: 38rem;
  font-size: 1.05rem;
  color: rgba(255, 255, 255, 0.92);
}

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  min-height: 46px;
  padding: 0.7rem 1.25rem;
  border-radius: 999px;
  font-weight: 700;
  border: 0;
  cursor: pointer;
  text-decoration: none;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.btn:hover {
  text-decoration: none;
  transform: translateY(-1px);
}

.btn-primary {
  background: #fff;
  color: var(--brand-deep);
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.18);
}

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

.btn-ghost {
  background: rgba(255, 255, 255, 0.12);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.45);
}

.btn-ghost:hover {
  color: #fff;
  background: rgba(255, 255, 255, 0.2);
}

.hero-visual {
  justify-self: end;
  width: min(100%, 280px);
  animation: floaty 5.5s ease-in-out infinite;
}

.hero-visual img {
  width: 100%;
  border-radius: 28px;
  box-shadow: 0 24px 50px rgba(0, 0, 0, 0.28);
}

@keyframes floaty {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-10px);
  }
}

.section {
  padding: 3.2rem 0;
}

.section-alt {
  background: rgba(255, 255, 255, 0.55);
  border-block: 1px solid rgba(215, 227, 239, 0.7);
}

.section-head {
  margin-bottom: 1.6rem;
  max-width: 46rem;
}

.section-head h2 {
  margin: 0 0 0.55rem;
  font-family: var(--display);
  font-size: clamp(1.55rem, 2.6vw, 2.1rem);
  font-weight: 400;
  color: var(--brand-deep);
}

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

.lead {
  font-size: 1.05rem;
  color: var(--ink);
}

.prose p,
.prose li {
  color: var(--ink);
}

.prose p {
  margin: 0 0 1rem;
}

.prose h2,
.prose h3 {
  color: var(--brand-deep);
  font-family: var(--display);
  font-weight: 400;
}

.prose h2 {
  margin: 2rem 0 0.8rem;
  font-size: 1.55rem;
}

.prose h3 {
  margin: 1.5rem 0 0.6rem;
  font-size: 1.2rem;
}

.prose ul,
.prose ol {
  margin: 0 0 1rem;
  padding-left: 1.2rem;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.1rem;
}

.feature-card {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: transform 0.25s ease;
}

.feature-card:hover {
  transform: translateY(-4px);
}

.feature-card img {
  width: 100%;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  object-position: top center;
  background: #dbe8f3;
}

.feature-card .body {
  padding: 1rem 1.05rem 1.15rem;
}

.feature-card h3 {
  margin: 0 0 0.4rem;
  font-size: 1.08rem;
  color: var(--brand-deep);
}

.feature-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  align-items: center;
}

.split.reverse .copy {
  order: 2;
}

.split img {
  width: 100%;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  object-fit: cover;
  max-height: 560px;
  object-position: top center;
}

.steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
  counter-reset: step;
}

.step {
  position: relative;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.2rem 1rem 1.15rem;
  box-shadow: var(--shadow);
}

.step::before {
  counter-increment: step;
  content: counter(step);
  display: inline-flex;
  width: 2rem;
  height: 2rem;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--brand), var(--accent));
  color: #fff;
  font-weight: 700;
  margin-bottom: 0.7rem;
}

.step h3 {
  margin: 0 0 0.4rem;
  font-size: 1.05rem;
}

.step p {
  margin: 0;
  color: var(--muted);
  font-size: 0.94rem;
}

.faq details {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0.85rem 1rem;
  margin-bottom: 0.7rem;
}

.faq summary {
  cursor: pointer;
  font-weight: 700;
  color: var(--brand-deep);
}

.faq p {
  margin: 0.7rem 0 0.2rem;
  color: var(--muted);
}

.cta-band {
  margin: 0.5rem 0 2.5rem;
  padding: 2rem;
  border-radius: 20px;
  background: linear-gradient(125deg, var(--brand-deep), var(--brand) 55%, var(--accent));
  color: #fff;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: center;
  justify-content: space-between;
  box-shadow: var(--shadow);
}

.cta-band h2 {
  margin: 0 0 0.35rem;
  font-family: var(--display);
  font-weight: 400;
  font-size: 1.7rem;
}

.cta-band p {
  margin: 0;
  color: rgba(255, 255, 255, 0.9);
}

.page-hero {
  padding: 2.4rem 0 1.4rem;
}

.page-hero h1 {
  margin: 0 0 0.55rem;
  font-family: var(--display);
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  font-weight: 400;
  color: var(--brand-deep);
}

.page-hero p {
  margin: 0;
  color: var(--muted);
  max-width: 44rem;
}

.breadcrumbs {
  margin-bottom: 0.8rem;
  font-size: 0.9rem;
  color: var(--muted);
}

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

.content-panel {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 1.5rem 1.4rem 1.7rem;
  box-shadow: var(--shadow);
  margin-bottom: 2.5rem;
}

.related {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: 1.2rem;
}

.related a {
  display: inline-flex;
  padding: 0.4rem 0.8rem;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: #f7fbfe;
  color: var(--brand-dark);
  font-size: 0.9rem;
}

.related a:hover {
  background: #eaf4fb;
  text-decoration: none;
}

.site-footer {
  background: #0b3658;
  color: rgba(255, 255, 255, 0.86);
  padding: 2.4rem 0 1.6rem;
  margin-top: 1rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

.site-footer h3 {
  margin: 0 0 0.7rem;
  font-size: 1rem;
  color: #fff;
}

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

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

.footer-links {
  display: grid;
  gap: 0.4rem;
}

.footer-brand {
  display: flex;
  gap: 0.75rem;
  align-items: flex-start;
}

.footer-brand img {
  width: 48px;
  height: 48px;
  border-radius: 12px;
}

.copyright {
  border-top: 1px solid rgba(255, 255, 255, 0.14);
  padding-top: 1rem;
  font-size: 0.88rem;
  color: rgba(255, 255, 255, 0.68);
}

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

.error-page h1 {
  margin: 0 0 0.6rem;
  font-family: var(--display);
  font-size: 3rem;
  color: var(--brand-deep);
  font-weight: 400;
}

.error-page p {
  margin: 0 0 1.2rem;
  color: var(--muted);
}

.toc {
  background: #f4f9fd;
  border: 1px dashed #b9d0e4;
  border-radius: 12px;
  padding: 0.9rem 1rem;
  margin: 0 0 1.4rem;
}

.toc strong {
  display: block;
  margin-bottom: 0.4rem;
  color: var(--brand-deep);
}

.toc a {
  display: inline-block;
  margin-right: 0.75rem;
  margin-bottom: 0.25rem;
}

.note {
  border-left: 4px solid var(--brand);
  background: #eef7fd;
  padding: 0.85rem 1rem;
  border-radius: 0 10px 10px 0;
  margin: 1rem 0;
}

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

  .split.reverse .copy {
    order: 0;
  }

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

@media (max-width: 760px) {
  .menu-toggle {
    display: inline-flex;
  }

  .nav-links {
    display: none;
    position: absolute;
    left: 1rem;
    right: 1rem;
    top: 68px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 0.85rem;
    box-shadow: var(--shadow);
    flex-direction: column;
    align-items: stretch;
    gap: 0.55rem;
  }

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

  .hero {
    padding: 2.2rem 0 1.8rem;
  }

  .hero .container,
  .feature-grid,
  .split,
  .steps,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .hero-visual {
    justify-self: center;
    width: min(100%, 220px);
  }

  .section {
    padding: 2.3rem 0;
  }

  .content-panel {
    padding: 1.15rem 1rem 1.3rem;
  }
}