:root {
  --color-primary: #1f3a5f;
  --color-primary-light: #3d6b8c;
  --color-accent: #e8a33d;
  --color-accent-soft: #f2c879;
  --color-bg: #f6f8fb;
  --color-bg-alt: #ffffff;
  --color-surface: rgba(255, 255, 255, 0.72);
  --color-surface-solid: #ffffff;
  --color-text: #1c2530;
  --color-text-soft: #4a5866;
  --color-text-muted: #6b7785;
  --color-border: rgba(31, 58, 95, 0.12);
  --color-shadow: rgba(31, 58, 95, 0.12);
  --gradient-hero: linear-gradient(135deg, #1f3a5f 0%, #2f5a82 45%, #e8a33d 100%);
  --gradient-accent: linear-gradient(120deg, #e8a33d 0%, #f2c879 100%);
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-pill: 999px;
  --space-xs: 0.5rem;
  --space-sm: 0.75rem;
  --space-md: 1.25rem;
  --space-lg: 2rem;
  --space-xl: 3rem;
  --space-2xl: 4.5rem;
  --max-width: 1180px;
  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --transition: 0.35s cubic-bezier(0.22, 1, 0.36, 1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-primary: #8fb6d9;
    --color-primary-light: #b6d2ea;
    --color-accent: #f0b558;
    --color-accent-soft: #f7d99a;
    --color-bg: #0f1722;
    --color-bg-alt: #16202d;
    --color-surface: rgba(28, 40, 54, 0.62);
    --color-surface-solid: #1a2531;
    --color-text: #e8eef5;
    --color-text-soft: #c3cfdb;
    --color-text-muted: #8e9caa;
    --color-border: rgba(143, 182, 217, 0.18);
    --color-shadow: rgba(0, 0, 0, 0.45);
    --gradient-hero: linear-gradient(135deg, #0f1722 0%, #1f3a5f 50%, #a86f1f 100%);
    --gradient-accent: linear-gradient(120deg, #f0b558 0%, #f7d99a 100%);
  }
}

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

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

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.8;
  color: var(--color-text);
  background-color: var(--color-bg);
  background-image:
    radial-gradient(circle at 12% 8%, rgba(232, 163, 61, 0.10), transparent 42%),
    radial-gradient(circle at 88% 0%, rgba(61, 107, 140, 0.14), transparent 46%);
  background-attachment: fixed;
  overflow-x: hidden;
}

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

a {
  color: var(--color-primary-light);
  text-decoration: none;
  transition: color var(--transition), opacity var(--transition);
}

a:hover,
a:focus-visible {
  color: var(--color-accent);
}

a:focus-visible,
button:focus-visible,
summary:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: 4px;
}

h1,
h2,
h3 {
  line-height: 1.35;
  color: var(--color-text);
  font-weight: 700;
  letter-spacing: 0.01em;
}

h1 {
  font-size: clamp(1.6rem, 3.6vw, 2.6rem);
  margin: 0 0 var(--space-md);
}

h2 {
  font-size: clamp(1.35rem, 2.6vw, 2rem);
  margin: 0 0 var(--space-md);
  padding-bottom: var(--space-sm);
  position: relative;
}

h2::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 64px;
  height: 4px;
  border-radius: var(--radius-pill);
  background: var(--gradient-accent);
}

h3 {
  font-size: clamp(1.05rem, 1.8vw, 1.25rem);
  margin: var(--space-lg) 0 var(--space-sm);
  color: var(--color-primary);
}

p {
  margin: 0 0 var(--space-md);
  color: var(--color-text-soft);
}

ul {
  margin: 0 0 var(--space-md);
  padding-left: 1.2rem;
}

li {
  margin-bottom: var(--space-xs);
  color: var(--color-text-soft);
}

/* ---------- Header ---------- */
header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(18px) saturate(160%);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  box-shadow: 0 8px 30px -18px var(--color-shadow);
}

.topbar {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs) var(--space-md);
  justify-content: space-between;
  align-items: center;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.55rem var(--space-md);
  font-size: 0.8rem;
  color: var(--color-text-muted);
  border-bottom: 1px solid var(--color-border);
}

.topbar span:first-child {
  font-weight: 600;
  color: var(--color-primary);
  letter-spacing: 0.02em;
}

.topbar span:last-child {
  font-variant-numeric: tabular-nums;
}

nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.65rem var(--space-md);
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  align-items: center;
}

nav a {
  position: relative;
  display: inline-block;
  padding: 0.4rem 0.85rem;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--color-text-soft);
  border-radius: var(--radius-pill);
  transition: color var(--transition), background var(--transition), transform var(--transition);
}

nav a::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 2px;
  width: 0;
  height: 2px;
  border-radius: var(--radius-pill);
  background: var(--gradient-accent);
  transform: translateX(-50%);
  transition: width var(--transition);
}

nav a:hover,
nav a:focus-visible {
  color: var(--color-primary);
  background: rgba(232, 163, 61, 0.12);
  transform: translateY(-2px);
}

nav a:hover::after,
nav a:focus-visible::after {
  width: 60%;
}

/* ---------- Main layout ---------- */
main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-lg) var(--space-md) var(--space-2xl);
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

section {
  position: relative;
  padding: var(--space-lg) clamp(1rem, 3vw, 2.25rem);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: 0 18px 48px -32px var(--color-shadow);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  animation: fadeRise 0.8s cubic-bezier(0.22, 1, 0.36, 1) both;
  transition: box-shadow var(--transition), transform var(--transition), border-color var(--transition);
}

section:hover {
  box-shadow: 0 26px 60px -34px var(--color-shadow);
  border-color: rgba(232, 163, 61, 0.35);
}

@keyframes fadeRise {
  from {
    opacity: 0;
    transform: translateY(26px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

section:nth-of-type(1) { animation-delay: 0.02s; }
section:nth-of-type(2) { animation-delay: 0.06s; }
section:nth-of-type(3) { animation-delay: 0.10s; }
section:nth-of-type(4) { animation-delay: 0.14s; }
section:nth-of-type(5) { animation-delay: 0.18s; }
section:nth-of-type(6) { animation-delay: 0.22s; }
section:nth-of-type(7) { animation-delay: 0.26s; }
section:nth-of-type(8) { animation-delay: 0.30s; }
section:nth-of-type(9) { animation-delay: 0.34s; }
section:nth-of-type(10) { animation-delay: 0.38s; }
section:nth-of-type(11) { animation-delay: 0.42s; }
section:nth-of-type(12) { animation-delay: 0.46s; }
section:nth-of-type(13) { animation-delay: 0.50s; }
section:nth-of-type(14) { animation-delay: 0.54s; }

/* ---------- Hero ---------- */
#home {
  overflow: hidden;
  background: var(--gradient-hero);
  color: #ffffff;
  border: none;
  padding: clamp(1.75rem, 4vw, 3rem);
}

#home::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 82% 18%, rgba(255, 255, 255, 0.24), transparent 40%),
    radial-gradient(circle at 12% 88%, rgba(232, 163, 61, 0.35), transparent 46%);
  pointer-events: none;
}

#home h1,
#home p {
  position: relative;
  color: #ffffff;
  text-shadow: 0 2px 18px rgba(0, 0, 0, 0.28);
}

#home p {
  color: rgba(255, 255, 255, 0.9);
  max-width: 72ch;
}

#home h1 {
  background: linear-gradient(90deg, #ffffff 0%, #ffe6b8 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  text-shadow: none;
  filter: drop-shadow(0 2px 12px rgba(0, 0, 0, 0.35));
}

.banner {
  position: relative;
  margin-top: var(--space-lg);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: 0 24px 60px -28px rgba(0, 0, 0, 0.55);
  border: 1px solid rgba(255, 255, 255, 0.22);
}

.banner figure {
  margin: 0;
  position: relative;
}

.banner svg {
  width: 100%;
  display: block;
  transition: transform 0.9s cubic-bezier(0.22, 1, 0.36, 1);
}

.banner:hover svg {
  transform: scale(1.04);
}

.banner figcaption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  padding: 1.4rem clamp(1rem, 3vw, 2rem) 1.1rem;
  font-size: clamp(0.95rem, 2vw, 1.2rem);
  font-weight: 600;
  letter-spacing: 0.04em;
  color: #ffffff;
  background: linear-gradient(180deg, transparent 0%, rgba(12, 20, 30, 0.72) 100%);
}

/* ---------- Articles ---------- */
#articles {
  display: flex;
  flex-direction: column;
}

#articles > p {
  margin-bottom: var(--space-lg);
}

#articles article {
  position: relative;
  padding: var(--space-md) clamp(1rem, 2.5vw, 1.6rem);
  margin-bottom: var(--space-md);
  background: var(--color-surface-solid);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  border-left: 4px solid var(--color-accent);
  box-shadow: 0 10px 30px -24px var(--color-shadow);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

#articles article::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: linear-gradient(120deg, rgba(232, 163, 61, 0.08), transparent 55%);
  opacity: 0;
  transition: opacity var(--transition);
  pointer-events: none;
}

#articles article:hover {
  transform: translateY(-4px);
  box-shadow: 0 22px 46px -28px var(--color-shadow);
  border-left-color: var(--color-primary-light);
}

#articles article:hover::before {
  opacity: 1;
}

#articles article h3 {
  margin-top: 0;
  color: var(--color-text);
}

#articles article h3::after {
  content: "";
  display: block;
  width: 40px;
  height: 3px;
  margin-top: var(--space-xs);
  border-radius: var(--radius-pill);
  background: var(--gradient-accent);
  opacity: 0.85;
}

#articles article > p:first-of-type {
  font-size: 0.82rem;
  color: var(--color-text-muted);
  letter-spacing: 0.03em;
  margin-bottom: var(--space-sm);
}

#articles article > p:nth-of-type(2) {
  color: var(--color-text-soft);
}

#articles article a {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-weight: 600;
  font-size: 0.92rem;
  padding: 0.4rem 1rem;
  border-radius: var(--radius-pill);
  color: var(--color-primary);
  background: rgba(232, 163, 61, 0.14);
  transition: background var(--transition), color var(--transition), transform var(--transition), box-shadow var(--transition);
}

#articles article a::after {
  content: "→";
  transition: transform var(--transition);
}

#articles article a:hover,
#articles article a:focus-visible {
  color: #ffffff;
  background: var(--gradient-accent);
  transform: translateY(-2px);
  box-shadow: 0 12px 26px -14px rgba(232, 163, 61, 0.85);
}

#articles article a:hover::after {
  transform: translateX(4px);
}

/* ---------- FAQ ---------- */
#faq details {
  margin-bottom: var(--space-sm);
  background: var(--color-surface-solid);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: box-shadow var(--transition), border-color var(--transition), transform var(--transition);
}

#faq details:hover {
  border-color: rgba(232, 163, 61, 0.45);
  box-shadow: 0 14px 34px -26px var(--color-shadow);
}

#faq details[open] {
  border-color: rgba(232, 163, 61, 0.6);
  box-shadow: 0 18px 40px -28px var(--color-shadow);
}

#faq summary {
  position: relative;
  list-style: none;
  cursor: pointer;
  padding: 0.95rem 3rem 0.95rem 1.1rem;
  font-weight: 600;
  color: var(--color-text);
  font-size: 0.98rem;
  transition: color var(--transition), background var(--transition);
  user-select: none;
}

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

#faq summary::after {
  content: "+";
  position: absolute;
  right: 1rem;
  top: 50%;
  transform: translateY(-50%);
  width: 26px;
  height: 26px;
  display: grid;
  place-items: center;
  font-size: 1.1rem;
  font-weight: 700;
  line-height: 1;
  color: var(--color-primary);
  background: rgba(232, 163, 61, 0.16);
  border-radius: 50%;
  transition: transform var(--transition), background var(--transition), color var(--transition);
}

#faq details[open] summary {
  color: var(--color-primary);
  background: rgba(232, 163, 61, 0.08);
}

#faq details[open] summary::after {
  content: "−";
  transform: translateY(-50%) rotate(180deg);
  color: #ffffff;
  background: var(--gradient-accent);
}

#faq details p {
  margin: 0;
  padding: 0 1.1rem 1.1rem;
  color: var(--color-text-soft);
  animation: fadeIn 0.4s ease both;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ---------- HowTo ---------- */
#howto h3 {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.25rem 0.85rem 0.25rem 0.5rem;
  border-radius: var(--radius-pill);
  background: rgba(61, 107, 140, 0.1);
  font-size: 1rem;
}

#howto h3::before {
  content: "▹";
  color: var(--color-accent);
  font-size: 1rem;
}

#howto p {
  padding-left: 0.85rem;
  border-left: 2px dashed var(--color-border);
  margin-left: 0.2rem;
}

/* ---------- Contact / Sitemap / Links ---------- */
#contact h3,
#sitemap h2,
#links h2,
#legal h2 {
  margin-top: var(--space-md);
}

#sitemap ul,
#links ul {
  list-style: none;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: var(--space-sm);
}

#sitemap li,
#links li {
  margin: 0;
}

#sitemap a,
#links a {
  display: block;
  padding: 0.55rem 0.9rem;
  font-size: 0.92rem;
  border-radius: var(--radius-sm);
  background: var(--color-surface-solid);
  border: 1px solid var(--color-border);
  color: var(--color-text-soft);
  transition: transform var(--transition), border-color var(--transition), color var(--transition), box-shadow var(--transition);
}

#sitemap a:hover,
#sitemap a:focus-visible,
#links a:hover,
#links a:focus-visible {
  color: var(--color-primary);
  border-color: var(--color-accent);
  transform: translateY(-3px);
  box-shadow: 0 14px 28px -22px var(--color-shadow);
}

/* ---------- Cases & News ---------- */
#cases h3,
#news h3 {
  position: relative;
  padding-left: 1rem;
}

#cases h3::before,
#news h3::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.35em;
  width: 6px;
  height: 1em;
  border-radius: var(--radius-pill);
  background: var(--gradient-accent);
}

#cases p:not(:last-child),
#news p {
  color: var(--color-text-soft);
}

#news h3 + p {
  font-size: 0.82rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-xs);
}

/* ---------- Products / Solutions ---------- */
#products h3,
#solutions h3,
#brand h3 {
  position: relative;
  padding-left: 1.1rem;
}

#products h3::before,
#solutions h3::before,
#brand h3::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.4em;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--gradient-accent);
  box-shadow: 0 0 0 4px rgba(232, 163, 61, 0.16);
}

/* ---------- Footer ---------- */
footer {
  position: relative;
  margin-top: var(--space-lg);
  padding: var(--space-xl) var(--space-md) var(--space-lg);
  text-align: center;
  color: rgba(255, 255, 255, 0.82);
  background: linear-gradient(150deg, #16263a 0%, #1f3a5f 55%, #2a4a6b 100%);
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  overflow: hidden;
}

footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 15% 20%, rgba(232, 163, 61, 0.18), transparent 42%),
    radial-gradient(circle at 85% 80%, rgba(61, 107, 140, 0.28), transparent 46%);
  pointer-events: none;
}

footer p {
  position: relative;
  margin: 0 0 var(--space-xs);
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.78);
  letter-spacing: 0.02em;
}

footer p:first-child {
  font-weight: 600;
  color: #ffffff;
  font-size: 0.92rem;
}

footer p:last-child {
  color: rgba(255, 255, 255, 0.62);
  font-size: 0.8rem;
}

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  :root {
    --space-lg: 1.6rem;
    --space-xl: 2.4rem;
    --space-2xl: 3.4rem;
  }

  nav {
    gap: 0.25rem;
  }

  nav a {
    padding: 0.35rem 0.7rem;
    font-size: 0.85rem;
  }

  section {
    border-radius: var(--radius-md);
  }
}

@media (max-width: 640px) {
  body {
    font-size: 15px;
    line-height: 1.75;
  }

  .topbar {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.15rem;
    padding: 0.5rem var(--space-sm);
    font-size: 0.74rem;
  }

  nav {
    flex-wrap: nowrap;
    overflow-x: auto;
    padding: 0.5rem var(--space-sm);
    scrollbar-width: none;
    -webkit-overflow-scrolling: touch;
  }

  nav::-webkit-scrollbar {
    display: none;
  }

  nav a {
    flex: 0 0 auto;
    white-space: nowrap;
    font-size: 0.82rem;
  }

  main {
    padding: var(--space-md) var(--space-sm) var(--space-xl);
    gap: var(--space-md);
  }

  section {
    padding: var(--space-md) var(--space-sm);
    border-radius: var(--radius-md);
  }

  #home {
    padding: var(--space-lg) var(--space-sm);
  }

  h2::after {
    width: 48px;
    height: 3px;
  }

  #sitemap ul,
  #links ul {
    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
  }

  #articles article {
    padding: var(--space-sm);
  }

  #faq summary {
    padding: 0.85rem 2.8rem 0.85rem 0.9rem;
    font-size: 0.92rem;
  }

  footer {
    padding: var(--space-lg) var(--space-sm);
  }
}

@media (max-width: 380px) {
  h1 {
    font-size: 1.4rem;
  }

  nav a {
    font-size: 0.78rem;
    padding: 0.3rem 0.6rem;
  }
}

/* ---------- Motion & accessibility ---------- */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }

  section {
    opacity: 1;
    transform: none;
  }
}

@media print {
  header,
  footer,
  nav {
    display: none;
  }

  body {
    background: #ffffff;
    color: #000000;
  }

  section {
    box-shadow: none;
    border: 1px solid #cccccc;
    break-inside: avoid;
  }
}