:root {
  --brand-start: #6d28d9;
  --brand-end: #db2777;
  --brand: #6d28d9;
  --brand-soft: #a78bfa;
  --accent: #db2777;
  --bg: #f6f4fb;
  --bg-alt: #ffffff;
  --surface: rgba(255, 255, 255, 0.72);
  --surface-solid: #ffffff;
  --surface-glass: rgba(255, 255, 255, 0.55);
  --border: rgba(109, 40, 217, 0.14);
  --border-strong: rgba(109, 40, 217, 0.3);
  --text: #241a36;
  --text-soft: #5b5170;
  --text-mute: #8a819e;
  --shadow-sm: 0 2px 8px rgba(36, 26, 54, 0.06);
  --shadow-md: 0 10px 30px rgba(36, 26, 54, 0.1);
  --shadow-lg: 0 24px 60px rgba(36, 26, 54, 0.16);
  --radius-sm: 10px;
  --radius: 18px;
  --radius-lg: 28px;
  --maxw: 1180px;
  --header-h: 72px;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
  --transition: 0.35s var(--ease);
}

html[data-theme="dark"] {
  --bg: #120c1f;
  --bg-alt: #1a1230;
  --surface: rgba(38, 28, 60, 0.72);
  --surface-solid: #221838;
  --surface-glass: rgba(38, 28, 60, 0.55);
  --border: rgba(167, 139, 250, 0.18);
  --border-strong: rgba(167, 139, 250, 0.38);
  --text: #f1ecff;
  --text-soft: #c3b8dd;
  --text-mute: #948aab;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 10px 30px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 24px 60px rgba(0, 0, 0, 0.55);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 16px);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.78;
  color: var(--text);
  background:
    radial-gradient(1200px 600px at 8% -10%, rgba(109, 40, 217, 0.14), transparent 60%),
    radial-gradient(1000px 520px at 100% 0%, rgba(219, 39, 119, 0.12), transparent 55%),
    var(--bg);
  background-attachment: fixed;
  transition: background-color 0.4s var(--ease), color 0.4s var(--ease);
  overflow-x: hidden;
}

@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;
  }
}

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

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

html[data-theme="dark"] a {
  color: var(--brand-soft);
}

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

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

h1, h2, h3, h4, h5, h6 {
  line-height: 1.35;
  margin: 0 0 0.6em;
  font-weight: 700;
  letter-spacing: 0.01em;
  color: var(--text);
}

h1 { font-size: clamp(1.75rem, 4.2vw, 2.75rem); }
h2 { font-size: clamp(1.4rem, 3vw, 2rem); }
h3 { font-size: clamp(1.15rem, 2.2vw, 1.4rem); }
h4 { font-size: 1.08rem; color: var(--text-soft); }

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

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

ul, ol { margin: 0 0 1.2em; padding-left: 1.3em; color: var(--text-soft); }
li { margin-bottom: 0.45em; }

blockquote {
  margin: 0 0 1.2em;
  padding: 1.1em 1.4em;
  border-left: 4px solid var(--brand);
  background: var(--surface-glass);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--text-soft);
}

blockquote p { margin: 0; }

time {
  font-size: 0.85rem;
  color: var(--text-mute);
  font-variant-numeric: tabular-nums;
}

/* ===== Skip link ===== */
body > a[href="#main-content"] {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 999;
  padding: 12px 22px;
  background: var(--brand);
  color: #fff;
  border-radius: 0 0 var(--radius-sm) 0;
  font-weight: 600;
}

body > a[href="#main-content"]:focus {
  left: 0;
  color: #fff;
}

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

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

header > div > a[aria-label] {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-size: 1.15rem;
  flex-shrink: 0;
}

header > div > a[aria-label] svg {
  width: 40px;
  height: 40px;
  border-radius: 12px;
  transition: transform var(--transition), box-shadow var(--transition);
  box-shadow: 0 6px 18px rgba(109, 40, 217, 0.35);
}

header > div > a[aria-label]:hover svg {
  transform: rotate(-6deg) scale(1.06);
  box-shadow: 0 10px 26px rgba(219, 39, 119, 0.4);
}

header > div > a[aria-label] strong {
  background: linear-gradient(120deg, var(--brand-start), var(--brand-end));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  font-size: 1.2rem;
  letter-spacing: 0.04em;
}

/* Nav */
header nav[aria-label="主导航"] {
  flex: 1 1 auto;
  min-width: 0;
}

header nav[aria-label="主导航"] ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 2px 4px;
}

header nav[aria-label="主导航"] li {
  margin: 0;
}

header nav[aria-label="主导航"] a {
  display: inline-block;
  padding: 7px 11px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-soft);
  border-radius: 999px;
  position: relative;
  transition: color var(--transition), background-color var(--transition), transform var(--transition);
}

header nav[aria-label="主导航"] a:hover,
header nav[aria-label="主导航"] a:focus-visible {
  color: var(--brand);
  background: rgba(109, 40, 217, 0.1);
  transform: translateY(-1px);
}

html[data-theme="dark"] header nav[aria-label="主导航"] a:hover {
  color: var(--brand-soft);
  background: rgba(167, 139, 250, 0.14);
}

/* Search */
header form[role="search"] {
  display: flex;
  align-items: center;
  gap: 6px;
  flex: 0 1 260px;
  min-width: 0;
}

header form[role="search"] label {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

header form[role="search"] input[type="search"] {
  flex: 1 1 auto;
  min-width: 0;
  padding: 9px 14px;
  font-size: 0.88rem;
  color: var(--text);
  background: var(--surface-glass);
  border: 1px solid var(--border);
  border-radius: 999px;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: border-color var(--transition), box-shadow var(--transition), background-color var(--transition);
}

header form[role="search"] input[type="search"]::placeholder {
  color: var(--text-mute);
}

header form[role="search"] input[type="search"]:focus {
  outline: none;
  border-color: var(--brand-soft);
  box-shadow: 0 0 0 3px rgba(109, 40, 217, 0.16);
  background: var(--surface-solid);
}

header form[role="search"] button {
  flex-shrink: 0;
  padding: 9px 16px;
  font-size: 0.88rem;
  font-weight: 600;
  color: #fff;
  background: linear-gradient(120deg, var(--brand-start), var(--brand-end));
  border: none;
  border-radius: 999px;
  cursor: pointer;
  transition: transform var(--transition), box-shadow var(--transition), filter var(--transition);
  box-shadow: 0 6px 16px rgba(109, 40, 217, 0.32);
}

header form[role="search"] button:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 22px rgba(219, 39, 119, 0.38);
  filter: brightness(1.05);
}

header form[role="search"] button:active {
  transform: translateY(0);
}

/* Theme toggle */
header button[aria-label="切换暗黑模式"] {
  flex-shrink: 0;
  padding: 9px 16px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-soft);
  background: var(--surface-glass);
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  cursor: pointer;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: color var(--transition), background-color var(--transition), transform var(--transition), border-color var(--transition);
}

header button[aria-label="切换暗黑模式"]:hover {
  color: var(--brand);
  border-color: var(--brand);
  transform: translateY(-2px);
  background: rgba(109, 40, 217, 0.1);
}

html[data-theme="dark"] header button[aria-label="切换暗黑模式"]:hover {
  color: var(--brand-soft);
  border-color: var(--brand-soft);
}

/* ===== Breadcrumb ===== */
body > nav[aria-label="面包屑导航"] {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 18px 20px 0;
}

body > nav[aria-label="面包屑导航"] ol {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  font-size: 0.85rem;
  color: var(--text-mute);
}

body > nav[aria-label="面包屑导航"] li {
  margin: 0;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

body > nav[aria-label="面包屑导航"] li + li::before {
  content: "/";
  color: var(--text-mute);
  opacity: 0.6;
}

body > nav[aria-label="面包屑导航"] a {
  color: var(--text-soft);
  padding: 2px 4px;
  border-radius: 6px;
  transition: color var(--transition), background-color var(--transition);
}

body > nav[aria-label="面包屑导航"] a:hover {
  color: var(--brand);
  background: rgba(109, 40, 217, 0.08);
}

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

html[data-theme="dark"] body > nav[aria-label="面包屑导航"] li[aria-current="page"] {
  color: var(--brand-soft);
}

/* ===== Main layout ===== */
main {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 24px 20px 80px;
}

main section {
  margin-bottom: 28px;
  padding: clamp(20px, 3.4vw, 40px);
  background: var(--surface);
  backdrop-filter: blur(16px) saturate(150%);
  -webkit-backdrop-filter: blur(16px) saturate(150%);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition), background-color var(--transition);
  scroll-margin-top: calc(var(--header-h) + 20px);
}

main section:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--border-strong);
}

/* Section heading accents */
main section > h2 {
  position: relative;
  padding-left: 18px;
}

main section > h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.18em;
  bottom: 0.18em;
  width: 6px;
  border-radius: 999px;
  background: linear-gradient(180deg, var(--brand-start), var(--brand-end));
}

main section h3 {
  margin-top: 1.6em;
  padding-bottom: 0.4em;
  border-bottom: 1px dashed var(--border);
}

main section h3:first-of-type {
  margin-top: 0.4em;
}

main section h4 {
  margin-top: 1.2em;
}

main section > ul,
main section > ol {
  padding-left: 1.4em;
}

main section > ul li::marker {
  color: var(--brand);
}

main section > ol li::marker {
  color: var(--brand);
  font-weight: 700;
}

/* ===== Hero ===== */
#hero {
  position: relative;
  overflow: hidden;
  background:
    linear-gradient(135deg, rgba(109, 40, 217, 0.92), rgba(219, 39, 119, 0.85)),
    var(--surface);
  border: 1px solid rgba(255, 255, 255, 0.16);
  color: #fff;
  isolation: isolate;
}

#hero::before {
  content: "";
  position: absolute;
  inset: -40% -20% auto auto;
  width: 70%;
  height: 160%;
  background: radial-gradient(closest-side, rgba(255, 255, 255, 0.28), transparent 70%);
  z-index: -1;
  animation: heroFloat 14s ease-in-out infinite alternate;
}

#hero::after {
  content: "";
  position: absolute;
  inset: auto auto -50% -20%;
  width: 60%;
  height: 140%;
  background: radial-gradient(closest-side, rgba(255, 255, 255, 0.18), transparent 70%);
  z-index: -1;
  animation: heroFloat 18s ease-in-out infinite alternate-reverse;
}

@keyframes heroFloat {
  from { transform: translate3d(0, 0, 0) scale(1); }
  to { transform: translate3d(-4%, 6%, 0) scale(1.12); }
}

#hero > h1 {
  color: #fff;
  text-shadow: 0 4px 24px rgba(0, 0, 0, 0.22);
  max-width: 22ch;
}

#hero > p {
  color: rgba(255, 255, 255, 0.92);
  max-width: 72ch;
}

#hero > div {
  margin: 26px 0 22px;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 26px 60px rgba(0, 0, 0, 0.32);
  border: 1px solid rgba(255, 255, 255, 0.2);
  transition: transform var(--transition), box-shadow var(--transition);
}

#hero > div:hover {
  transform: translateY(-4px) scale(1.005);
  box-shadow: 0 34px 74px rgba(0, 0, 0, 0.4);
}

#hero > div svg {
  width: 100%;
  height: auto;
  display: block;
}

#hero > ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
}

#hero > ul li {
  margin: 0;
  padding: 12px 16px;
  background: rgba(255, 255, 255, 0.14);
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: var(--radius-sm);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  color: rgba(255, 255, 255, 0.92);
  font-size: 0.92rem;
  transition: background-color var(--transition), transform var(--transition), border-color var(--transition);
}

#hero > ul li:hover {
  background: rgba(255, 255, 255, 0.24);
  border-color: rgba(255, 255, 255, 0.4);
  transform: translateY(-2px);
}

#hero > ul li strong {
  color: #fff;
}

/* ===== Cards inside sections (articles / news / cases) ===== */
#news article,
#articles article {
  position: relative;
  margin: 0 0 16px;
  padding: 20px 22px;
  background: var(--surface-solid);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

#news article:last-child,
#articles article:last-child {
  margin-bottom: 0;
}

#news article:hover,
#articles article:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--border-strong);
}

#news article h3,
#articles article h3 {
  margin-top: 0;
  border-bottom: none;
  padding-bottom: 0;
  font-size: 1.12rem;
}

#news article h3::after,
#articles article h3::after {
  content: "";
  display: block;
  width: 40px;
  height: 3px;
  margin-top: 10px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--brand-start), var(--brand-end));
  transition: width var(--transition);
}

#news article:hover h3::after,
#articles article:hover h3::after {
  width: 72px;
}

#news article time,
#articles article time {
  display: inline-block;
  margin-bottom: 8px;
  padding: 2px 10px;
  font-size: 0.78rem;
  background: rgba(109, 40, 217, 0.1);
  color: var(--brand);
  border-radius: 999px;
}

html[data-theme="dark"] #news article time,
html[data-theme="dark"] #articles article time {
  background: rgba(167, 139, 250, 0.16);
  color: var(--brand-soft);
}

#articles article a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-weight: 600;
  font-size: 0.9rem;
  padding: 6px 14px;
  border-radius: 999px;
  background: linear-gradient(120deg, var(--brand-start), var(--brand-end));
  color: #fff;
  transition: transform var(--transition), box-shadow var(--transition), filter var(--transition);
  box-shadow: 0 6px 16px rgba(109, 40, 217, 0.28);
}

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

#articles article a:hover {
  color: #fff;
  transform: translateY(-2px);
  box-shadow: 0 10px 24px rgba(219, 39, 119, 0.36);
  filter: brightness(1.06);
}

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

/* ===== Testimonials ===== */
#testimonials blockquote {
  position: relative;
  padding-left: 3.2em;
  background: linear-gradient(135deg, rgba(109, 40, 217, 0.08), rgba(219, 39, 119, 0.06));
  border-left: 4px solid transparent;
  border-image: linear-gradient(180deg, var(--brand-start), var(--brand-end)) 1;
  transition: transform var(--transition), box-shadow var(--transition);
}

#testimonials blockquote::before {
  content: "“";
  position: absolute;
  left: 0.35em;
  top: 0.02em;
  font-size: 3rem;
  line-height: 1;
  font-family: Georgia, "Times New Roman", serif;
  color: var(--brand);
  opacity: 0.5;
}

#testimonials blockquote:hover {
  transform: translateX(4px);
  box-shadow: var(--shadow-sm);
}

/* ===== FAQ details ===== */
#faq details {
  margin: 0 0 12px;
  background: var(--surface-solid);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}

#faq details:last-of-type {
  margin-bottom: 0;
}

#faq details[open] {
  border-color: var(--border-strong);
  box-shadow: var(--shadow-md);
}

#faq details:hover {
  border-color: var(--border-strong);
}

#faq summary {
  position: relative;
  padding: 16px 52px 16px 20px;
  font-weight: 600;
  font-size: 1rem;
  color: var(--text);
  cursor: pointer;
  list-style: none;
  transition: background-color var(--transition), color var(--transition);
  user-select: none;
}

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

#faq summary::after {
  content: "+";
  position: absolute;
  right: 18px;
  top: 50%;
  transform: translateY(-50%);
  width: 26px;
  height: 26px;
  display: grid;
  place-items: center;
  font-size: 1.2rem;
  font-weight: 400;
  line-height: 1;
  color: #fff;
  background: linear-gradient(135deg, var(--brand-start), var(--brand-end));
  border-radius: 50%;
  transition: transform var(--transition), filter var(--transition);
}

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

#faq summary:hover {
  background: rgba(109, 40, 217, 0.06);
  color: var(--brand);
}

html[data-theme="dark"] #faq summary:hover {
  color: var(--brand-soft);
  background: rgba(167, 139, 250, 0.1);
}

#faq details > p {
  margin: 0;
  padding: 0 20px 18px;
  color: var(--text-soft);
  animation: fadeSlide 0.35s var(--ease);
}

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

/* ===== HowTo ===== */
#howto ol {
  counter-reset: step;
  list-style: none;
  padding-left: 0;
}

#howto ol li {
  position: relative;
  padding: 12px 16px 12px 52px;
  margin-bottom: 10px;
  background: var(--surface-solid);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
}

#howto ol li::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 14px;
  top: 12px;
  width: 26px;
  height: 26px;
  display: grid;
  place-items: center;
  font-size: 0.82rem;
  font-weight: 700;
  color: #fff;
  background: linear-gradient(135deg, var(--brand-start), var(--brand-end));
  border-radius: 50%;
}

#howto ol li:hover {
  transform: translateX(4px);
  border-color: var(--border-strong);
  box-shadow: var(--shadow-sm);
}

#howto ul li {
  position: relative;
}

/* ===== Contact & Sitemap & Links ===== */
#contact ul,
#sitemap ul,
#links ul {
  list-style: none;
  padding-left: 0;
}

#sitemap ul,
#links ul {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 10px;
}

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

#sitemap a,
#links a {
  display: block;
  padding: 10px 14px;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-soft);
  background: var(--surface-solid);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: transform var(--transition), color var(--transition), border-color var(--transition), box-shadow var(--transition), background-color var(--transition);
}

#sitemap a:hover,
#links a:hover {
  color: #fff;
  background: linear-gradient(120deg, var(--brand-start), var(--brand-end));
  border-color: transparent;
  transform: translateY(-3px);
  box-shadow: 0 10px 22px rgba(109, 40, 217, 0.3);
}

#contact ul li {
  padding: 10px 14px;
  background: var(--surface-solid);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: border-color var(--transition), transform var(--transition);
}

#contact ul li:hover {
  border-color: var(--border-strong);
  transform: translateY(-2px);
}

/* ===== Footer ===== */
footer {
  position: relative;
  background: linear-gradient(160deg, rgba(109, 40, 217, 0.96), rgba(219, 39, 119, 0.9));
  color: rgba(255, 255, 255, 0.9);
  padding: 56px 20px 40px;
  margin-top: 20px;
}

footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(600px 300px at 90% 0%, rgba(255, 255, 255, 0.16), transparent 60%),
    radial-gradient(500px 260px at 0% 100%, rgba(255, 255, 255, 0.12), transparent 60%);
  pointer-events: none;
}

footer > div {
  position: relative;
  max-width: var(--maxw);
  margin: 0 auto 26px;
  padding: 22px 24px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: var(--radius);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: background-color var(--transition), border-color var(--transition), transform var(--transition);
}

footer > div:hover {
  background: rgba(255, 255, 255, 0.13);
  border-color: rgba(255, 255, 255, 0.28);
  transform: translateY(-2px);
}

footer > div:last-child {
  margin-bottom: 0;
}

footer h2,
footer h3 {
  color: #fff;
  margin-top: 0;
}

footer h2 {
  font-size: 1.4rem;
}

footer h3 {
  font-size: 1rem;
  padding-bottom: 8px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.18);
}

footer p {
  color: rgba(255, 255, 255, 0.82);
  margin: 0 0 0.5em;
  font-size: 0.9rem;
}

footer a {
  color: #fff;
  text-decoration: underline;
  text-underline-offset: 3px;
}

footer a:hover {
  color: #ffe4f1;
}

/* ===== Back to top ===== */
body > button[aria-label="返回顶部"] {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 120;
  width: 50px;
  height: 50px;
  padding: 0;
  font-size: 0.72rem;
  font-weight: 700;
  line-height: 1.1;
  color: #fff;
  background: linear-gradient(135deg, var(--brand-start), var(--brand-end));
  border: none;
  border-radius: 50%;
  cursor: pointer;
  box-shadow: 0 12px 28px rgba(109, 40, 217, 0.42);
  transition: transform var(--transition), box-shadow var(--transition), filter var(--transition);
}

body > button[aria-label="返回顶部"]:hover {
  transform: translateY(-4px) scale(1.06);
  box-shadow: 0 18px 36px rgba(219, 39, 119, 0.5);
  filter: brightness(1.08);
}

body > button[aria-label="返回顶部"]:active {
  transform: translateY(0) scale(0.98);
}

/* ===== Scroll reveal ===== */
@supports (animation-timeline: view()) {
  main section {
    animation: revealUp linear both;
    animation-timeline: view();
    animation-range: entry 0% cover 26%;
  }
}

@keyframes revealUp {
  from {
    opacity: 0;
    transform: translateY(36px) scale(0.985);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@media (prefers-reduced-motion: reduce) {
  main section {
    animation: none !important;
  }
}

/* ===== Responsive ===== */
@media (max-width: 1080px) {
  header nav[aria-label="主导航"] a {
    padding: 6px 9px;
    font-size: 0.85rem;
  }
}

@media (max-width: 900px) {
  :root { --header-h: 64px; }

  header > div {
    gap: 10px;
    padding: 10px 16px;
  }

  header nav[aria-label="主导航"] {
    order: 4;
    flex-basis: 100%;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }

  header nav[aria-label="主导航"]::-webkit-scrollbar {
    display: none;
  }

  header nav[aria-label="主导航"] ul {
    flex-wrap: nowrap;
    width: max-content;
    padding-bottom: 2px;
  }

  header form[role="search"] {
    flex: 1 1 180px;
    order: 2;
  }

  header button[aria-label="切换暗黑模式"] {
    order: 3;
    padding: 8px 12px;
    font-size: 0.8rem;
  }

  main {
    padding: 18px 16px 64px;
  }

  main section {
    margin-bottom: 20px;
    border-radius: var(--radius);
  }

  footer {
    padding: 40px 16px 32px;
  }
}

@media (max-width: 600px) {
  body {
    font-size: 15px;
    line-height: 1.72;
  }

  header > div > a[aria-label] strong {
    font-size: 1.05rem;
  }

  header > div > a[aria-label] svg {
    width: 34px;
    height: 34px;
  }

  header form[role="search"] {
    flex-basis: 100%;
    order: 5;
  }

  header form[role="search"] input[type="search"] {
    padding: 8px 12px;
  }

  header form[role="search"] button {
    padding: 8px 14px;
  }

  body > nav[aria-label="面包屑导航"] {
    padding: 14px 16px 0;
    font-size: 0.8rem;
  }

  main section {
    padding: 18px 16px;
  }

  main section > h2 {
    padding-left: 14px;
  }

  main section > h2::before {
    width: 5px;
  }

  #hero > h1 {
    max-width: none;
  }

  #hero > ul {
    grid-template-columns: 1fr;
  }

  #hero > ul li {
    padding: 10px 12px;
    font-size: 0.86rem;
  }

  #news article,
  #articles article {
    padding: 16px;
  }

  #testimonials blockquote {
    padding: 1em 1em 1em 2.6em;
  }

  #faq summary {
    padding: 14px 48px 14px 16px;
    font-size: 0.94rem;
  }

  #faq details > p {
    padding: 0 16px 16px;
  }

  #howto ol li {
    padding: 10px 12px 10px 46px;
  }

  #howto ol li::before {
    left: 12px;
    top: 10px;
    width: 24px;
    height: 24px;
  }

  #sitemap ul,
  #links ul {
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 8px;
  }

  footer > div {
    padding: 18px 16px;
  }

  body > button[aria-label="返回顶部"] {
    right: 14px;
    bottom: 14px;
    width: 44px;
    height: 44px;
    font-size: 0.66rem;
  }
}

@media (max-width: 380px) {
  header button[aria-label="切换暗黑模式"] {
    padding: 7px 10px;
    font-size: 0.74rem;
  }

  main section {
    padding: 16px 13px;
  }
}

/* ===== High contrast / forced colors ===== */
@media (forced-colors: active) {
  main section,
  #news article,
  #articles article,
  #faq details {
    border: 1px solid CanvasText;
  }
}

/* ===== Print ===== */
@media print {
  header,
  body > nav[aria-label="面包屑导航"],
  body > button[aria-label="返回顶部"],
  footer::before {
    display: none;
  }

  body {
    background: #fff;
    color: #000;
  }

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

  #hero {
    background: #f3f0fa;
    color: #000;
  }

  #hero > h1,
  #hero > p,
  #hero > ul li,
  #hero > ul li strong {
    color: #000;
  }
}