:root {
  --blue: #1a8cff;
  --blue-deep: #0d5fb8;
  --blue-soft: #e8f4ff;
  --ink: #142033;
  --muted: #5a6a7e;
  --line: #d7e4f2;
  --bg: #f3f8fd;
  --white: #ffffff;
  --accent: #00c2a8;
  --radius: 14px;
  --shadow: 0 12px 40px rgba(13, 95, 184, 0.1);
  --font-display: "Outfit", "Noto Sans SC", sans-serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --max: 1120px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--ink);
  background:
    radial-gradient(1200px 500px at 10% -10%, #cfe8ff 0%, transparent 55%),
    radial-gradient(900px 420px at 100% 0%, #d7fff6 0%, transparent 50%),
    linear-gradient(180deg, #f7fbff 0%, var(--bg) 40%, #eef5fb 100%);
  line-height: 1.75;
  font-size: 16px;
}

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

a {
  color: var(--blue-deep);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--blue);
}

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

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(14px);
  background: rgba(255, 255, 255, 0.86);
  border-bottom: 1px solid rgba(215, 228, 242, 0.9);
}

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

.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  color: var(--ink);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.02em;
}

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

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.35rem 1.1rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  color: var(--ink);
  font-size: 0.95rem;
  font-weight: 500;
  padding: 0.35rem 0;
  position: relative;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--blue), var(--accent));
  transition: width 0.25s ease;
}

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--white);
  cursor: pointer;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
}

.nav-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--ink);
  transition: 0.2s ease;
}

/* Hero */
.hero {
  position: relative;
  overflow: hidden;
  padding: 3.2rem 0 2.6rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 2.5rem;
  align-items: center;
}

.hero-copy h1 {
  margin: 0 0 0.85rem;
  font-family: var(--font-display);
  font-size: clamp(2rem, 4.2vw, 3.1rem);
  line-height: 1.2;
  letter-spacing: -0.02em;
  background: linear-gradient(120deg, var(--ink) 20%, var(--blue-deep) 70%, var(--accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-lead {
  margin: 0 0 1.4rem;
  color: var(--muted);
  font-size: 1.05rem;
  max-width: 36rem;
}

.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: 600;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn:hover {
  transform: translateY(-2px);
}

.btn-primary {
  background: linear-gradient(135deg, var(--blue) 0%, var(--blue-deep) 100%);
  color: var(--white);
  box-shadow: 0 10px 24px rgba(26, 140, 255, 0.28);
}

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

.btn-ghost {
  background: rgba(255, 255, 255, 0.75);
  border-color: var(--line);
  color: var(--ink);
}

.hero-visual {
  position: relative;
}

.hero-visual img {
  width: 100%;
  border-radius: 22px;
  box-shadow: var(--shadow);
  border: 1px solid rgba(255, 255, 255, 0.7);
  animation: floaty 5.5s ease-in-out infinite;
}

.hero-glow {
  position: absolute;
  inset: 12% -8% -8% 12%;
  background: radial-gradient(circle, rgba(26, 140, 255, 0.28), transparent 70%);
  z-index: -1;
  filter: blur(18px);
}

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

/* Sections */
.section {
  padding: 3.2rem 0;
}

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

.section-head h2 {
  margin: 0 0 0.55rem;
  font-family: var(--font-display);
  font-size: clamp(1.55rem, 2.6vw, 2.1rem);
  line-height: 1.25;
}

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

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

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

.prose h2,
.prose h3 {
  font-family: var(--font-display);
  margin: 1.8rem 0 0.7rem;
  line-height: 1.3;
}

.prose h2 {
  font-size: 1.55rem;
}

.prose h3 {
  font-size: 1.2rem;
}

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

.prose li {
  margin-bottom: 0.4rem;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.2rem;
}

.feature-item {
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1rem;
  box-shadow: 0 8px 24px rgba(20, 32, 51, 0.04);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

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

.feature-item img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
  border-radius: 10px;
  margin-bottom: 0.85rem;
  background: #eaf3fb;
}

.feature-item h3 {
  margin: 0 0 0.4rem;
  font-size: 1.05rem;
  font-family: var(--font-display);
}

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

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.8rem;
  align-items: center;
}

.split.reverse .split-media {
  order: 2;
}

.split-media img {
  border-radius: 18px;
  box-shadow: var(--shadow);
  border: 1px solid var(--line);
}

.guide-list {
  display: grid;
  gap: 1rem;
}

.guide-step {
  display: grid;
  grid-template-columns: 56px 1fr;
  gap: 0.9rem;
  background: rgba(255, 255, 255, 0.8);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1rem 1.1rem;
}

.step-num {
  width: 56px;
  height: 56px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  font-family: var(--font-display);
  font-weight: 700;
  color: var(--white);
  background: linear-gradient(145deg, var(--blue), var(--accent));
}

.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  margin: 1rem 0 0;
}

.chip {
  display: inline-flex;
  padding: 0.35rem 0.75rem;
  border-radius: 999px;
  background: var(--blue-soft);
  color: var(--blue-deep);
  font-size: 0.86rem;
  font-weight: 600;
}

.media-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1rem;
}

.media-row img {
  width: 100%;
  aspect-ratio: 9 / 16;
  object-fit: cover;
  object-position: top;
  border-radius: 14px;
  border: 1px solid var(--line);
  box-shadow: 0 8px 20px rgba(20, 32, 51, 0.06);
  transition: transform 0.25s ease;
}

.media-row img:hover {
  transform: scale(1.02);
}

.cta-band {
  margin: 1rem 0 0;
  padding: 1.6rem;
  border-radius: 18px;
  background:
    linear-gradient(135deg, rgba(26, 140, 255, 0.12), rgba(0, 194, 168, 0.12)),
    var(--white);
  border: 1px solid var(--line);
}

.cta-band h3 {
  margin: 0 0 0.45rem;
  font-family: var(--font-display);
}

.cta-band p {
  margin: 0 0 0.9rem;
  color: var(--muted);
}

.page-hero {
  padding: 2.4rem 0 1rem;
}

.page-hero h1 {
  margin: 0 0 0.6rem;
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 3.5vw, 2.5rem);
}

.page-hero p {
  margin: 0;
  color: var(--muted);
  max-width: 42rem;
}

.legal-box {
  background: rgba(255, 255, 255, 0.85);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 1.5rem 1.4rem 1.2rem;
  box-shadow: 0 8px 24px rgba(20, 32, 51, 0.04);
}

.error-page {
  min-height: 70vh;
  display: grid;
  place-items: center;
  text-align: center;
  padding: 3rem 0;
}

.error-page h1 {
  margin: 0 0 0.5rem;
  font-size: clamp(2.4rem, 6vw, 4rem);
  font-family: var(--font-display);
  background: linear-gradient(120deg, var(--blue), var(--accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

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

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

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

.toc {
  background: var(--blue-soft);
  border-radius: 14px;
  padding: 1rem 1.1rem;
  margin: 0 0 1.4rem;
}

.toc strong {
  display: block;
  margin-bottom: 0.4rem;
}

.toc a {
  display: inline-block;
  margin: 0.15rem 0.7rem 0.15rem 0;
}

/* Footer */
.site-footer {
  margin-top: 2rem;
  padding: 2.2rem 0 1.6rem;
  background: linear-gradient(180deg, transparent, rgba(13, 95, 184, 0.06));
  border-top: 1px solid var(--line);
}

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

.footer-brand {
  display: flex;
  gap: 0.8rem;
  align-items: flex-start;
}

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

.footer-brand strong {
  display: block;
  font-family: var(--font-display);
  margin-bottom: 0.25rem;
}

.footer-brand p,
.footer-col p {
  margin: 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.footer-col h4 {
  margin: 0 0 0.55rem;
  font-family: var(--font-display);
  font-size: 1rem;
}

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

.footer-col li {
  margin-bottom: 0.35rem;
}

.footer-col a {
  color: var(--muted);
}

.footer-col a:hover {
  color: var(--blue-deep);
}

.copyright {
  margin-top: 1.6rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.88rem;
  text-align: center;
}

/* Motion */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }
}

.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

.reveal.show {
  opacity: 1;
  transform: none;
}

/* Responsive */
@media (max-width: 960px) {
  .hero-grid,
  .split,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .split.reverse .split-media {
    order: 0;
  }

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

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

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

  .nav-links {
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 0.6rem 1rem 1rem;
    background: rgba(255, 255, 255, 0.97);
    border-bottom: 1px solid var(--line);
  }

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

  .nav-links a {
    padding: 0.75rem 0.2rem;
    border-bottom: 1px solid #eef3f8;
  }

  .hero {
    padding-top: 2rem;
  }

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

  .guide-step {
    grid-template-columns: 46px 1fr;
  }

  .step-num {
    width: 46px;
    height: 46px;
    border-radius: 12px;
  }
}

@media (max-width: 480px) {
  .media-row {
    grid-template-columns: 1fr 1fr;
    gap: 0.7rem;
  }

  .hero-actions {
    width: 100%;
  }

  .btn {
    width: 100%;
  }
}