:root {
  --bg: #0f1020;
  --bg-2: #14152b;
  --surface: rgba(255, 255, 255, 0.06);
  --surface-strong: rgba(255, 255, 255, 0.1);
  --border: rgba(255, 255, 255, 0.12);
  --text: #eef0f6;
  --text-soft: #b8bdd0;
  --text-dim: #8a90a8;
  --brand: #ff6b6b;
  --brand-2: #feca57;
  --brand-3: #48dbfb;
  --brand-4: #1dd1a1;
  --link: #7fe3ff;
  --radius-lg: 22px;
  --radius-md: 14px;
  --radius-sm: 10px;
  --shadow: 0 18px 50px rgba(0, 0, 0, 0.45);
  --shadow-soft: 0 8px 24px rgba(0, 0, 0, 0.28);
  --glass: blur(16px) saturate(140%);
  --maxw: 1180px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #f4f6fb;
    --bg-2: #eef1f8;
    --surface: rgba(255, 255, 255, 0.72);
    --surface-strong: rgba(255, 255, 255, 0.9);
    --border: rgba(20, 24, 48, 0.1);
    --text: #1a1a2e;
    --text-soft: #3d4360;
    --text-dim: #6b7190;
    --link: #0b6fa8;
    --shadow: 0 18px 50px rgba(26, 26, 46, 0.12);
    --shadow-soft: 0 8px 24px rgba(26, 26, 46, 0.08);
  }
}

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

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

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
  color: var(--text);
  background:
    radial-gradient(1100px 600px at 12% -8%, rgba(255, 107, 107, 0.16), transparent 60%),
    radial-gradient(900px 520px at 88% 4%, rgba(72, 219, 251, 0.14), transparent 62%),
    radial-gradient(800px 600px at 50% 100%, rgba(29, 209, 161, 0.1), transparent 65%),
    linear-gradient(180deg, var(--bg) 0%, var(--bg-2) 100%);
  background-attachment: fixed;
  min-height: 100vh;
  overflow-x: hidden;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: var(--link);
  text-decoration: none;
  transition: color 0.25s var(--ease), opacity 0.25s var(--ease);
}

a:hover,
a:focus-visible {
  color: var(--brand-2);
}

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--brand-3);
  outline-offset: 3px;
  border-radius: 6px;
}

h1, h2, h3, h4 {
  line-height: 1.3;
  margin: 0 0 0.6em;
  letter-spacing: 0.01em;
  font-weight: 700;
}

h1 {
  font-size: clamp(1.7rem, 4.2vw, 2.9rem);
  background: linear-gradient(100deg, #fff 0%, var(--brand-2) 45%, var(--brand) 78%, var(--brand-3) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  filter: drop-shadow(0 4px 18px rgba(255, 107, 107, 0.25));
}

h2 {
  font-size: clamp(1.35rem, 2.8vw, 1.95rem);
  position: relative;
  padding-left: 18px;
}

h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.18em;
  bottom: 0.18em;
  width: 6px;
  border-radius: 999px;
  background: linear-gradient(180deg, var(--brand), var(--brand-2), var(--brand-3));
  box-shadow: 0 0 18px rgba(255, 107, 107, 0.55);
}

h3 {
  font-size: clamp(1.08rem, 1.8vw, 1.3rem);
  color: var(--text);
}

p {
  margin: 0 0 1em;
  color: var(--text-soft);
}

ul,
ol {
  margin: 0 0 1em;
  padding-left: 1.35em;
  color: var(--text-soft);
}

li {
  margin-bottom: 0.45em;
}

li::marker {
  color: var(--brand);
}

strong {
  color: var(--text);
  font-weight: 700;
}

blockquote {
  margin: 1.1em 0;
  padding: 16px 20px;
  border-left: 4px solid var(--brand);
  border-radius: var(--radius-sm);
  background: var(--surface);
  backdrop-filter: var(--glass);
  -webkit-backdrop-filter: var(--glass);
  box-shadow: var(--shadow-soft);
  transition: transform 0.35s var(--ease), border-color 0.35s var(--ease);
}

blockquote:hover {
  transform: translateX(6px);
  border-color: var(--brand-3);
}

blockquote p {
  margin: 0;
  color: var(--text);
}

/* ---------- Header ---------- */
header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: linear-gradient(180deg, rgba(15, 16, 32, 0.82), rgba(15, 16, 32, 0.55));
  backdrop-filter: var(--glass);
  -webkit-backdrop-filter: var(--glass);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
}

@media (prefers-color-scheme: light) {
  header {
    background: linear-gradient(180deg, rgba(255, 255, 255, 0.85), rgba(255, 255, 255, 0.6));
  }
}

header > div {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  align-items: center;
  gap: 22px;
  flex-wrap: wrap;
}

header > div > a {
  font-size: 1.22rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  padding: 6px 16px;
  border-radius: 999px;
  color: #fff;
  background: linear-gradient(120deg, var(--brand) 0%, #ff8f6b 50%, var(--brand-2) 100%);
  box-shadow: 0 8px 22px rgba(255, 107, 107, 0.35);
  white-space: nowrap;
  transition: transform 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

header > div > a:hover,
header > div > a:focus-visible {
  color: #fff;
  transform: translateY(-2px) scale(1.03);
  box-shadow: 0 12px 30px rgba(255, 107, 107, 0.5);
}

header nav {
  flex: 1 1 auto;
  min-width: 0;
}

header nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 4px 6px;
}

header nav li {
  margin: 0;
}

header nav a {
  display: inline-block;
  padding: 7px 13px;
  border-radius: 999px;
  font-size: 0.9rem;
  color: var(--text-soft);
  border: 1px solid transparent;
  transition: all 0.28s var(--ease);
}

header nav a:hover,
header nav a:focus-visible {
  color: var(--text);
  background: var(--surface-strong);
  border-color: var(--border);
  transform: translateY(-2px);
  box-shadow: var(--shadow-soft);
}

/* ---------- Main layout ---------- */
main {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 26px 20px 60px;
  display: block;
}

main > section {
  margin: 0 0 30px;
  padding: clamp(20px, 3.4vw, 38px);
  border-radius: var(--radius-lg);
  background: var(--surface);
  border: 1px solid var(--border);
  backdrop-filter: var(--glass);
  -webkit-backdrop-filter: var(--glass);
  box-shadow: var(--shadow-soft);
  transition: transform 0.5s var(--ease), box-shadow 0.5s var(--ease), border-color 0.5s var(--ease);
  animation: rise 0.75s var(--ease) both;
  scroll-margin-top: 96px;
}

main > section:nth-of-type(2) { animation-delay: 0.05s; }
main > section:nth-of-type(3) { animation-delay: 0.1s; }
main > section:nth-of-type(4) { animation-delay: 0.15s; }
main > section:nth-of-type(5) { animation-delay: 0.2s; }

main > section:hover {
  border-color: rgba(255, 107, 107, 0.34);
  box-shadow: var(--shadow);
}

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

@supports (animation-timeline: view()) {
  main > section {
    animation: rise linear both;
    animation-timeline: view();
    animation-range: entry 0% cover 26%;
  }
}

/* ---------- Breadcrumb ---------- */
main > nav[aria-label="面包屑导航"] {
  margin-bottom: 22px;
}

main > nav[aria-label="面包屑导航"] ol {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 10px 18px;
  border-radius: 999px;
  background: var(--surface);
  border: 1px solid var(--border);
  backdrop-filter: var(--glass);
  -webkit-backdrop-filter: var(--glass);
  font-size: 0.88rem;
}

main > nav[aria-label="面包屑导航"] li {
  margin: 0;
  color: var(--text-dim);
}

main > nav[aria-label="面包屑导航"] li + li::before {
  content: "›";
  margin-right: 8px;
  color: var(--brand);
}

main > nav[aria-label="面包屑导航"] li[aria-current="page"] {
  color: var(--text);
  font-weight: 600;
}

/* ---------- Hero ---------- */
#hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(680px 320px at 8% 0%, rgba(255, 107, 107, 0.3), transparent 62%),
    radial-gradient(560px 300px at 92% 10%, rgba(72, 219, 251, 0.26), transparent 64%),
    radial-gradient(520px 340px at 50% 120%, rgba(254, 202, 87, 0.2), transparent 66%),
    linear-gradient(135deg, rgba(255, 107, 107, 0.14), rgba(72, 219, 251, 0.1) 55%, rgba(29, 209, 161, 0.12));
  border: 1px solid rgba(255, 255, 255, 0.16);
}

#hero::after {
  content: "";
  position: absolute;
  inset: -40% -10% auto auto;
  width: 420px;
  height: 420px;
  border-radius: 50%;
  background: conic-gradient(from 90deg, rgba(255, 107, 107, 0.34), rgba(254, 202, 87, 0.26), rgba(72, 219, 251, 0.3), rgba(29, 209, 161, 0.24), rgba(255, 107, 107, 0.34));
  filter: blur(60px);
  opacity: 0.6;
  pointer-events: none;
  animation: spin 22s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

#hero > * {
  position: relative;
  z-index: 1;
}

#hero p {
  font-size: clamp(0.96rem, 1.5vw, 1.06rem);
  max-width: 78ch;
}

#hero figure {
  margin: 26px 0 0;
  padding: 16px;
  border-radius: var(--radius-lg);
  background: var(--surface-strong);
  border: 1px solid var(--border);
  backdrop-filter: var(--glass);
  -webkit-backdrop-filter: var(--glass);
  box-shadow: var(--shadow);
  transition: transform 0.5s var(--ease), box-shadow 0.5s var(--ease);
}

#hero figure:hover {
  transform: translateY(-6px) scale(1.008);
  box-shadow: 0 26px 60px rgba(0, 0, 0, 0.5);
}

#hero figure svg {
  width: 100%;
  border-radius: var(--radius-md);
}

#hero figcaption {
  margin-top: 12px;
  font-size: 0.85rem;
  color: var(--text-dim);
  text-align: center;
}

/* ---------- Articles ---------- */
#articles {
  display: block;
}

#articles article {
  position: relative;
  margin: 0 0 18px;
  padding: 20px 22px;
  border-radius: var(--radius-md);
  background: var(--surface);
  border: 1px solid var(--border);
  backdrop-filter: var(--glass);
  -webkit-backdrop-filter: var(--glass);
  transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease), border-color 0.4s var(--ease), background 0.4s var(--ease);
}

#articles article::before {
  content: "";
  position: absolute;
  left: 0;
  top: 16px;
  bottom: 16px;
  width: 4px;
  border-radius: 999px;
  background: linear-gradient(180deg, var(--brand), var(--brand-3));
  opacity: 0;
  transform: scaleY(0.4);
  transition: opacity 0.4s var(--ease), transform 0.4s var(--ease);
}

#articles article:hover {
  transform: translateY(-4px);
  background: var(--surface-strong);
  border-color: rgba(72, 219, 251, 0.36);
  box-shadow: var(--shadow);
}

#articles article:hover::before {
  opacity: 1;
  transform: scaleY(1);
}

#articles article h3 {
  margin-bottom: 6px;
}

#articles article > p:first-of-type {
  font-size: 0.82rem;
  color: var(--text-dim);
  margin-bottom: 10px;
  letter-spacing: 0.02em;
}

#articles article > p:last-of-type {
  margin-bottom: 0;
}

#articles article a {
  display: inline-block;
  margin-top: 4px;
  padding: 6px 16px;
  border-radius: 999px;
  font-size: 0.86rem;
  font-weight: 600;
  color: #fff;
  background: linear-gradient(120deg, var(--brand), #ff8f6b);
  box-shadow: 0 6px 18px rgba(255, 107, 107, 0.32);
  transition: transform 0.3s var(--ease), box-shadow 0.3s var(--ease), filter 0.3s var(--ease);
}

#articles article a:hover,
#articles article a:focus-visible {
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 10px 26px rgba(255, 107, 107, 0.5);
  filter: brightness(1.06);
}

/* ---------- FAQ ---------- */
#faq h3 {
  margin-top: 26px;
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  background: linear-gradient(100deg, rgba(255, 107, 107, 0.14), rgba(72, 219, 251, 0.1));
  border: 1px solid var(--border);
  transition: background 0.35s var(--ease), transform 0.35s var(--ease);
}

#faq h3:hover {
  transform: translateX(4px);
  background: linear-gradient(100deg, rgba(255, 107, 107, 0.24), rgba(72, 219, 251, 0.18));
}

#faq h3 + p {
  margin-top: 0;
  padding: 0 4px;
}

/* ---------- HowTo ---------- */
#howto h3 {
  color: var(--brand-2);
}

#howto p {
  max-width: 80ch;
}

/* ---------- Contact / Sitemap / Links lists ---------- */
#contact ul,
#sitemap ul,
#links ul {
  list-style: none;
  padding: 0;
  display: grid;
  gap: 10px;
}

#contact ul li,
#sitemap ul li,
#links ul li {
  margin: 0;
  padding: 11px 16px;
  border-radius: var(--radius-sm);
  background: var(--surface);
  border: 1px solid var(--border);
  transition: transform 0.3s var(--ease), border-color 0.3s var(--ease), background 0.3s var(--ease);
}

#contact ul li:hover,
#sitemap ul li:hover,
#links ul li:hover {
  transform: translateX(5px);
  border-color: rgba(254, 202, 87, 0.45);
  background: var(--surface-strong);
}

#sitemap ul,
#links ul {
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
}

#sitemap ul li a,
#links ul li a {
  display: block;
  font-weight: 600;
}

/* ---------- News list ---------- */
#news ul {
  list-style: none;
  padding: 0;
  display: grid;
  gap: 10px;
}

#news ul li {
  margin: 0;
  padding: 12px 16px 12px 20px;
  position: relative;
  border-radius: var(--radius-sm);
  background: var(--surface);
  border: 1px solid var(--border);
  transition: transform 0.3s var(--ease), border-color 0.3s var(--ease);
}

#news ul li::before {
  content: "";
  position: absolute;
  left: 8px;
  top: 50%;
  width: 6px;
  height: 6px;
  margin-top: -3px;
  border-radius: 50%;
  background: var(--brand-4);
  box-shadow: 0 0 10px var(--brand-4);
}

#news ul li:hover {
  transform: translateX(5px);
  border-color: rgba(29, 209, 161, 0.45);
}

/* ---------- Knowledge ---------- */
#knowledge h3 {
  color: var(--brand-3);
}

/* ---------- Footer ---------- */
footer {
  margin-top: 20px;
  padding: 34px 20px 44px;
  text-align: center;
  border-top: 1px solid var(--border);
  background: linear-gradient(180deg, transparent, rgba(0, 0, 0, 0.22));
}

footer p {
  margin: 0 0 8px;
  font-size: 0.86rem;
  color: var(--text-dim);
}

footer p:first-child {
  font-size: 0.95rem;
  color: var(--text-soft);
  font-weight: 600;
}

footer a {
  font-weight: 600;
}

/* ---------- Responsive ---------- */
@media (max-width: 860px) {
  header > div {
    padding: 10px 14px;
    gap: 10px;
  }

  header nav ul {
    gap: 2px 4px;
  }

  header nav a {
    padding: 6px 10px;
    font-size: 0.84rem;
  }

  main {
    padding: 18px 14px 46px;
  }

  main > section {
    margin-bottom: 22px;
    border-radius: 18px;
  }

  #articles article {
    padding: 16px 16px 16px 18px;
  }
}

@media (max-width: 560px) {
  body {
    font-size: 15px;
    line-height: 1.7;
  }

  header > div {
    flex-direction: column;
    align-items: flex-start;
  }

  header nav {
    width: 100%;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }

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

  header nav ul {
    flex-wrap: nowrap;
    padding-bottom: 4px;
  }

  header nav a {
    white-space: nowrap;
  }

  h2 {
    padding-left: 14px;
  }

  h2::before {
    width: 5px;
  }

  #sitemap ul,
  #links ul {
    grid-template-columns: 1fr;
  }

  #hero figure {
    padding: 10px;
  }
}

/* ---------- Motion & print ---------- */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}

@media print {
  body {
    background: #fff;
    color: #000;
  }

  header,
  footer,
  main > nav[aria-label="面包屑导航"] {
    display: none;
  }

  main > section {
    box-shadow: none;
    border: 1px solid #ccc;
    backdrop-filter: none;
    animation: none;
  }
}