:root {
  --primary: #ff5a3c;
  --primary-dark: #e64528;
  --primary-light: #ff7d66;
  --accent: #6c5ce7;
  --accent-2: #00b894;
  --bg: #f7f8fc;
  --bg-elevated: #ffffff;
  --bg-glass: rgba(255, 255, 255, 0.72);
  --bg-glass-border: rgba(255, 255, 255, 0.55);
  --text: #1f2430;
  --text-secondary: #5a6273;
  --text-muted: #8b93a5;
  --border: #e6e9f0;
  --shadow-sm: 0 2px 8px rgba(31, 36, 48, 0.06);
  --shadow-md: 0 8px 24px rgba(31, 36, 48, 0.08);
  --shadow-lg: 0 16px 48px rgba(31, 36, 48, 0.12);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;
  --radius-xl: 32px;
  --header-h: 68px;
  --transition: 0.28s cubic-bezier(0.4, 0, 0.2, 1);
  --gradient-hero: linear-gradient(135deg, #ff5a3c 0%, #ff8a5c 45%, #ffc46b 100%);
  --gradient-accent: linear-gradient(135deg, #6c5ce7 0%, #a29bfe 100%);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

[data-theme="dark"] {
  --bg: #0f1218;
  --bg-elevated: #181d27;
  --bg-glass: rgba(24, 29, 39, 0.72);
  --bg-glass-border: rgba(255, 255, 255, 0.08);
  --text: #eef1f7;
  --text-secondary: #a8b0c0;
  --text-muted: #6f7889;
  --border: #262d3a;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.45);
  --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.55);
  --gradient-hero: linear-gradient(135deg, #b33a24 0%, #c25a2f 45%, #a86a1f 100%);
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--font);
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.75;
  font-size: 16px;
  min-height: 100vh;
  overflow-x: hidden;
  transition: background-color var(--transition), color var(--transition);
  background-image:
    radial-gradient(circle at 12% 8%, rgba(255, 90, 60, 0.08), transparent 42%),
    radial-gradient(circle at 88% 22%, rgba(108, 92, 231, 0.08), transparent 40%);
  background-attachment: fixed;
}

[data-theme="dark"] body {
  background-image:
    radial-gradient(circle at 12% 8%, rgba(255, 90, 60, 0.12), transparent 42%),
    radial-gradient(circle at 88% 22%, rgba(108, 92, 231, 0.14), transparent 40%);
}

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

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

a:hover {
  color: var(--primary-dark);
}

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

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

li {
  margin-bottom: 0.5em;
}

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

h1 {
  font-size: clamp(1.6rem, 4vw, 2.5rem);
  margin-bottom: 0.7em;
  background: var(--gradient-hero);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

h2 {
  font-size: clamp(1.35rem, 3vw, 1.9rem);
  margin-bottom: 0.75em;
  position: relative;
  padding-left: 18px;
}

h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.18em;
  bottom: 0.18em;
  width: 5px;
  border-radius: 3px;
  background: var(--gradient-hero);
}

h3 {
  font-size: clamp(1.08rem, 2.2vw, 1.3rem);
  margin-top: 1.4em;
  margin-bottom: 0.55em;
  color: var(--text);
}

p {
  margin-bottom: 1em;
  color: var(--text-secondary);
}

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

time {
  color: var(--text-muted);
  font-size: 0.86em;
}

address {
  font-style: normal;
}

/* ============ Header ============ */
#site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg-glass);
  -webkit-backdrop-filter: blur(18px) saturate(180%);
  backdrop-filter: blur(18px) saturate(180%);
  border-bottom: 1px solid var(--bg-glass-border);
  transition: background var(--transition), box-shadow var(--transition);
}

#site-header.scrolled {
  box-shadow: var(--shadow-md);
}

.header-inner {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 20px;
  min-height: var(--header-h);
  display: flex;
  align-items: center;
  gap: 20px;
}

.brand {
  flex-shrink: 0;
}

.brand a {
  display: inline-flex;
  border-radius: var(--radius-sm);
  transition: transform var(--transition), box-shadow var(--transition);
}

.brand a:hover {
  transform: translateY(-2px) scale(1.03);
  box-shadow: 0 8px 20px rgba(255, 90, 60, 0.35);
}

.brand svg {
  border-radius: 8px;
}

nav[aria-label="主导航"] {
  flex: 1;
  min-width: 0;
}

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

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

nav[aria-label="主导航"] a {
  display: inline-block;
  padding: 8px 13px;
  border-radius: 999px;
  color: var(--text-secondary);
  font-size: 0.92rem;
  font-weight: 500;
  white-space: nowrap;
  position: relative;
  transition: color var(--transition), background var(--transition), transform var(--transition);
}

nav[aria-label="主导航"] a::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 3px;
  width: 0;
  height: 2px;
  border-radius: 2px;
  background: var(--gradient-hero);
  transform: translateX(-50%);
  transition: width var(--transition);
}

nav[aria-label="主导航"] a:hover {
  color: var(--primary);
  background: rgba(255, 90, 60, 0.08);
  transform: translateY(-1px);
}

nav[aria-label="主导航"] a:hover::after {
  width: 55%;
}

.header-tools {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.header-tools form {
  display: flex;
  align-items: center;
  gap: 0;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 3px 3px 3px 14px;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.header-tools form:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 4px rgba(255, 90, 60, 0.15);
}

.header-tools label {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

.header-tools input[type="search"] {
  border: none;
  background: transparent;
  color: var(--text);
  font-size: 0.9rem;
  font-family: inherit;
  width: 170px;
  padding: 6px 4px;
  outline: none;
}

.header-tools input[type="search"]::placeholder {
  color: var(--text-muted);
}

.header-tools button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  border-radius: 999px;
  font-size: 0.88rem;
  font-weight: 600;
  padding: 8px 16px;
  transition: transform var(--transition), box-shadow var(--transition),
    background var(--transition), color var(--transition);
}

.header-tools form button[type="submit"] {
  background: var(--gradient-hero);
  color: #fff;
  box-shadow: 0 4px 12px rgba(255, 90, 60, 0.3);
}

.header-tools form button[type="submit"]:hover {
  transform: translateY(-1px) scale(1.03);
  box-shadow: 0 6px 18px rgba(255, 90, 60, 0.45);
}

#theme-toggle,
#mobile-menu-btn {
  background: var(--bg-elevated);
  color: var(--text-secondary);
  border: 1px solid var(--border);
  padding: 8px 14px;
}

#theme-toggle:hover,
#mobile-menu-btn:hover {
  color: var(--primary);
  border-color: var(--primary);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

#mobile-menu-btn {
  display: none;
}

/* ============ Breadcrumb ============ */
nav[aria-label="面包屑导航"] {
  max-width: 1240px;
  margin: 0 auto;
  padding: 14px 20px 0;
}

nav[aria-label="面包屑导航"] ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  list-style: none;
  padding: 0;
  font-size: 0.85rem;
  color: var(--text-muted);
}

nav[aria-label="面包屑导航"] li {
  margin: 0;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

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

nav[aria-label="面包屑导航"] a {
  color: var(--text-secondary);
}

nav[aria-label="面包屑导航"] a:hover {
  color: var(--primary);
}

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

/* ============ Main layout ============ */
main {
  max-width: 1240px;
  margin: 0 auto;
  padding: 24px 20px 64px;
}

main > section {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: clamp(22px, 4vw, 44px);
  margin-bottom: 28px;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
  transition: box-shadow var(--transition), transform var(--transition),
    border-color var(--transition);
  opacity: 0;
  transform: translateY(28px);
  animation: fadeUp 0.7s cubic-bezier(0.22, 1, 0.36, 1) forwards;
}

main > section::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  background: linear-gradient(135deg, rgba(255, 90, 60, 0.03), transparent 55%);
}

main > section:hover {
  box-shadow: var(--shadow-md);
  border-color: rgba(255, 90, 60, 0.25);
}

main > section:nth-child(1) { animation-delay: 0.02s; }
main > section:nth-child(2) { animation-delay: 0.06s; }
main > section:nth-child(3) { animation-delay: 0.1s; }
main > section:nth-child(4) { animation-delay: 0.14s; }
main > section:nth-child(5) { animation-delay: 0.18s; }
main > section:nth-child(6) { animation-delay: 0.22s; }
main > section:nth-child(7) { animation-delay: 0.26s; }
main > section:nth-child(8) { animation-delay: 0.3s; }
main > section:nth-child(9) { animation-delay: 0.34s; }
main > section:nth-child(10) { animation-delay: 0.38s; }
main > section:nth-child(11) { animation-delay: 0.42s; }
main > section:nth-child(12) { animation-delay: 0.46s; }
main > section:nth-child(13) { animation-delay: 0.5s; }
main > section:nth-child(14) { animation-delay: 0.54s; }
main > section:nth-child(15) { animation-delay: 0.58s; }
main > section:nth-child(16) { animation-delay: 0.62s; }
main > section:nth-child(17) { animation-delay: 0.66s; }
main > section:nth-child(18) { animation-delay: 0.7s; }
main > section:nth-child(19) { animation-delay: 0.74s; }

@keyframes fadeUp {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ============ Hero ============ */
#hero {
  background: var(--gradient-hero);
  color: #fff;
  border: none;
  overflow: hidden;
  isolation: isolate;
}

#hero::before {
  content: "";
  position: absolute;
  top: -120px;
  right: -120px;
  width: 380px;
  height: 380px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.16);
  filter: blur(10px);
  z-index: -1;
  animation: floatBlob 9s ease-in-out infinite;
}

#hero::after {
  content: "";
  position: absolute;
  bottom: -160px;
  left: -100px;
  width: 320px;
  height: 320px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.1);
  filter: blur(14px);
  z-index: -1;
  animation: floatBlob 11s ease-in-out infinite reverse;
}

@keyframes floatBlob {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(-24px, 20px) scale(1.08); }
}

#hero h1 {
  background: none;
  -webkit-text-fill-color: #fff;
  color: #fff;
  text-shadow: 0 2px 16px rgba(0, 0, 0, 0.18);
}

#hero p {
  color: rgba(255, 255, 255, 0.94);
  font-size: clamp(0.95rem, 1.6vw, 1.06rem);
  max-width: 900px;
  text-shadow: 0 1px 8px rgba(0, 0, 0, 0.12);
}

#hero .banner {
  margin: 26px 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  position: relative;
  transition: transform var(--transition), box-shadow var(--transition);
}

#hero .banner:hover {
  transform: translateY(-4px) scale(1.006);
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.28);
}

#hero .banner svg {
  width: 100%;
  display: block;
}

#hero .stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
  margin-top: 8px;
}

#hero .stats > div {
  background: rgba(255, 255, 255, 0.16);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.28);
  border-radius: var(--radius-md);
  padding: 18px 12px;
  text-align: center;
  transition: transform var(--transition), background var(--transition),
    box-shadow var(--transition);
}

#hero .stats > div:hover {
  transform: translateY(-4px);
  background: rgba(255, 255, 255, 0.26);
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.18);
}

#hero .stats strong {
  display: block;
  font-size: clamp(1.25rem, 3vw, 1.9rem);
  font-weight: 800;
  color: #fff;
  line-height: 1.2;
  font-variant-numeric: tabular-nums;
}

#hero .stats span {
  display: block;
  font-size: 0.82rem;
  color: rgba(255, 255, 255, 0.88);
  margin-top: 4px;
}

/* ============ Lists & cards inside sections ============ */
main section ul,
main section ol {
  color: var(--text-secondary);
}

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

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

#brand ul,
#advantages ul,
#applications ul,
#notice ul,
#howto ul,
#howto ol {
  list-style: none;
  padding-left: 0;
  display: grid;
  gap: 10px;
}

#brand ul li,
#advantages ul li,
#notice ul li,
#howto ul li,
#howto ol li {
  position: relative;
  padding: 12px 16px 12px 44px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: transform var(--transition), border-color var(--transition),
    box-shadow var(--transition), background var(--transition);
}

#brand ul li::before,
#advantages ul li::before,
#notice ul li::before,
#howto ul li::before {
  content: "";
  position: absolute;
  left: 16px;
  top: 50%;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--gradient-hero);
  transform: translateY(-50%);
  box-shadow: 0 0 0 4px rgba(255, 90, 60, 0.14);
}

#howto ol {
  counter-reset: step;
}

#howto ol li {
  padding-left: 52px;
  counter-increment: step;
}

#howto ol li::before {
  content: counter(step);
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--gradient-hero);
  color: #fff;
  font-size: 0.82rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 10px rgba(255, 90, 60, 0.3);
}

#brand ul li:hover,
#advantages ul li:hover,
#notice ul li:hover,
#howto ul li:hover,
#howto ol li:hover {
  transform: translateX(4px);
  border-color: rgba(255, 90, 60, 0.35);
  box-shadow: var(--shadow-sm);
}

/* ============ Products / Solutions / Applications cards ============ */
#products h3,
#solutions h3,
#applications h3,
#tech h3,
#howto h3,
#notice h3,
#team h3 {
  display: flex;
  align-items: center;
  gap: 10px;
}

#products h3::before,
#solutions h3::before,
#applications h3::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 2px;
  background: var(--gradient-accent);
  flex-shrink: 0;
  transform: rotate(45deg);
}

#products p,
#solutions p {
  padding-left: 2px;
}

/* ============ News articles ============ */
#news article,
#tech article {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 20px 22px;
  margin-bottom: 16px;
  position: relative;
  transition: transform var(--transition), box-shadow var(--transition),
    border-color var(--transition), background var(--transition);
}

#news article::before,
#tech article::before {
  content: "";
  position: absolute;
  left: 0;
  top: 16px;
  bottom: 16px;
  width: 4px;
  border-radius: 0 4px 4px 0;
  background: var(--gradient-hero);
  opacity: 0.7;
  transition: opacity var(--transition), width var(--transition);
}

#news article:hover,
#tech article:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: rgba(255, 90, 60, 0.3);
  background: var(--bg-elevated);
}

#news article:hover::before,
#tech article:hover::before {
  opacity: 1;
  width: 6px;
}

#news article h3,
#tech article h3 {
  margin-top: 0;
  font-size: clamp(1.02rem, 2vw, 1.18rem);
}

#news article h3 a {
  color: var(--text);
  background-image: linear-gradient(var(--primary), var(--primary));
  background-size: 0% 2px;
  background-repeat: no-repeat;
  background-position: 0 100%;
  transition: background-size var(--transition), color var(--transition);
}

#news article h3 a:hover {
  color: var(--primary);
  background-size: 100% 2px;
}

#news article time {
  display: inline-block;
  font-size: 0.8rem;
  padding: 2px 10px;
  border-radius: 999px;
  background: rgba(255, 90, 60, 0.1);
  color: var(--primary);
  margin-bottom: 8px;
  font-weight: 600;
}

#news article > a:last-child {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-weight: 600;
  font-size: 0.9rem;
  padding: 6px 14px;
  border-radius: 999px;
  background: rgba(255, 90, 60, 0.1);
  transition: background var(--transition), transform var(--transition),
    box-shadow var(--transition);
}

#news article > a:last-child::after {
  content: "→";
  transition: transform var(--transition);
}

#news article > a:last-child:hover {
  background: var(--gradient-hero);
  color: #fff;
  transform: translateY(-1px);
  box-shadow: 0 6px 16px rgba(255, 90, 60, 0.35);
}

#news article > a:last-child:hover::after {
  transform: translateX(4px);
}

/* ============ Testimonials ============ */
#testimonials blockquote {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 22px 24px 18px;
  margin-bottom: 16px;
  position: relative;
  transition: transform var(--transition), box-shadow var(--transition),
    border-color var(--transition);
}

#testimonials blockquote::before {
  content: "\201C";
  position: absolute;
  top: -8px;
  left: 18px;
  font-size: 3.4rem;
  line-height: 1;
  color: var(--primary);
  opacity: 0.25;
  font-family: Georgia, serif;
}

#testimonials blockquote:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: rgba(255, 90, 60, 0.3);
}

#testimonials blockquote p {
  color: var(--text);
  font-size: 1rem;
  margin-bottom: 10px;
  padding-left: 8px;
}

#testimonials blockquote footer {
  color: var(--text-muted);
  font-size: 0.88rem;
  text-align: right;
  font-weight: 600;
}

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

#faq details[open] {
  border-color: rgba(255, 90, 60, 0.35);
  box-shadow: var(--shadow-sm);
  background: var(--bg-elevated);
}

#faq details:hover {
  border-color: rgba(255, 90, 60, 0.3);
}

#faq summary {
  cursor: pointer;
  padding: 16px 48px 16px 20px;
  font-weight: 600;
  color: var(--text);
  font-size: clamp(0.95rem, 1.8vw, 1.04rem);
  list-style: none;
  position: relative;
  transition: color var(--transition), background var(--transition);
  user-select: none;
}

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

#faq summary::after {
  content: "";
  position: absolute;
  right: 20px;
  top: 50%;
  width: 9px;
  height: 9px;
  border-right: 2px solid var(--primary);
  border-bottom: 2px solid var(--primary);
  transform: translateY(-70%) rotate(45deg);
  transition: transform var(--transition);
}

#faq details[open] summary::after {
  transform: translateY(-30%) rotate(-135deg);
}

#faq summary:hover {
  color: var(--primary);
  background: rgba(255, 90, 60, 0.05);
}

#faq details p {
  padding: 0 20px 18px;
  margin: 0;
  animation: fadeIn 0.35s ease;
}

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

/* ============ Contact ============ */
#contact address {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 22px 24px;
  margin-bottom: 18px;
  display: grid;
  gap: 10px;
}

#contact address p {
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  align-items: baseline;
}

#contact address p::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--gradient-hero);
  flex-shrink: 0;
  margin-top: 0.55em;
}

/* ============ Sitemap & links ============ */
#sitemap ul,
#links ul {
  list-style: none;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

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

#sitemap a,
#links a {
  display: inline-block;
  padding: 7px 16px;
  border-radius: 999px;
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  font-size: 0.88rem;
  font-weight: 500;
  transition: all var(--transition);
}

#sitemap a:hover,
#links a:hover {
  color: #fff;
  background: var(--gradient-hero);
  border-color: transparent;
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(255, 90, 60, 0.32);
}

/* ============ Footer ============ */
footer {
  background: var(--bg-elevated);
  border-top: 1px solid var(--border);
  padding: clamp(32px, 5vw, 56px) 20px 28px;
  position: relative;
}

footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-hero);
}

footer > section {
  max-width: 1240px;
  margin: 0 auto 20px;
  padding: 0 0 18px;
  border-bottom: 1px dashed var(--border);
}

footer > section:last-of-type {
  border-bottom: none;
}

footer h2 {
  font-size: 1rem;
  padding-left: 0;
  margin-bottom: 8px;
  color: var(--text);
}

footer h2::before {
  display: none;
}

footer p {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 0;
  max-width: 900px;
}

footer > p {
  max-width: 1240px;
  margin: 18px auto 0;
  text-align: center;
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* ============ Back to top ============ */
#back-to-top {
  position: fixed;
  right: 22px;
  bottom: 26px;
  z-index: 90;
  width: 52px;
  height: 52px;
  border: none;
  border-radius: 50%;
  background: var(--gradient-hero);
  color: #fff;
  font-size: 0.72rem;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 8px 24px rgba(255, 90, 60, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px) scale(0.9);
  transition: opacity var(--transition), transform var(--transition),
    visibility var(--transition), box-shadow var(--transition);
  font-family: inherit;
  line-height: 1.2;
  padding: 0;
}

#back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0) scale(1);
}

#back-to-top:hover {
  transform: translateY(-4px) scale(1.06);
  box-shadow: 0 14px 32px rgba(255, 90, 60, 0.55);
}

#back-to-top:active {
  transform: translateY(-1px) scale(0.98);
}

/* ============ Scrollbar ============ */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

::-webkit-scrollbar-track {
  background: var(--bg);
}

::-webkit-scrollbar-thumb {
  background: rgba(255, 90, 60, 0.35);
  border-radius: 999px;
  border: 2px solid var(--bg);
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(255, 90, 60, 0.6);
}

::selection {
  background: rgba(255, 90, 60, 0.25);
  color: var(--text);
}

/* ============ Responsive ============ */
@media (max-width: 1080px) {
  .header-inner {
    flex-wrap: wrap;
    padding-top: 10px;
    padding-bottom: 10px;
    gap: 12px;
  }

  nav[aria-label="主导航"] {
    order: 3;
    flex-basis: 100%;
  }

  nav[aria-label="主导航"] ul {
    justify-content: flex-start;
    overflow-x: auto;
    flex-wrap: nowrap;
    padding-bottom: 4px;
    scrollbar-width: none;
  }

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

  .header-tools {
    margin-left: auto;
  }

  .header-tools input[type="search"] {
    width: 130px;
  }
}

@media (max-width: 768px) {
  :root {
    --header-h: 58px;
  }

  body {
    font-size: 15px;
  }

  .header-inner {
    padding: 8px 16px;
    gap: 10px;
  }

  .brand svg {
    width: 96px;
    height: 32px;
  }

  .header-tools form {
    padding-left: 10px;
  }

  .header-tools input[type="search"] {
    width: 100px;
    font-size: 0.85rem;
  }

  .header-tools button {
    padding: 7px 12px;
    font-size: 0.82rem;
  }

  #theme-toggle {
    padding: 7px 10px;
  }

  #mobile-menu-btn {
    display: inline-block;
  }

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

  nav[aria-label="主导航"].open {
    display: block;
  }

  nav[aria-label="主导航"] ul {
    flex-direction: column;
    flex-wrap: wrap;
    overflow: visible;
    gap: 2px;
  }

  nav[aria-label="主导航"] a {
    display: block;
    padding: 10px 14px;
    border-radius: var(--radius-sm);
  }

  main {
    padding: 16px 14px 48px;
  }

  main > section {
    padding: 20px 16px;
    border-radius: var(--radius-md);
    margin-bottom: 18px;
  }

  #hero .stats {
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
  }

  #hero .stats > div {
    padding: 14px 8px;
  }

  h2 {
    padding-left: 14px;
  }

  h2::before {
    width: 4px;
  }

  #news article,
  #tech article,
  #testimonials blockquote {
    padding: 16px 16px 16px 18px;
  }

  #contact address {
    padding: 16px 16px;
  }

  #back-to-top {
    width: 44px;
    height: 44px;
    right: 14px;
    bottom: 16px;
    font-size: 0.66rem;
  }

  footer {
    padding: 28px 16px 22px;
  }
}

@media (max-width: 480px) {
  .header-tools form {
    display: none;
  }

  #hero .stats {
    grid-template-columns: 1fr 1fr;
  }

  #hero .stats strong {
    font-size: 1.25rem;
  }

  #hero .stats span {
    font-size: 0.74rem;
  }

  #sitemap a,
  #links a {
    padding: 6px 12px;
    font-size: 0.82rem;
  }

  #brand ul li,
  #advantages ul li,
  #notice ul li,
  #howto ul li {
    padding: 10px 12px 10px 38px;
  }

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

/* ============ Motion preferences ============ */
@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;
  }

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

/* ============ Print ============ */
@media print {
  #site-header,
  #back-to-top,
  .header-tools,
  nav[aria-label="面包屑导航"] {
    display: none !important;
  }

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

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

  #hero {
    background: #eee !important;
    color: #000;
  }

  #hero h1,
  #hero p {
    color: #000 !important;
    -webkit-text-fill-color: #000;
  }
}