:root {
  --primary: #e8452c;
  --primary-dark: #c5321e;
  --primary-light: #ff6b52;
  --accent: #ffb347;
  --accent-2: #7c5cff;
  --bg: #f7f5f2;
  --bg-alt: #ffffff;
  --surface: rgba(255, 255, 255, 0.72);
  --surface-solid: #ffffff;
  --text: #1f1b18;
  --text-soft: #5a524c;
  --text-muted: #8a807a;
  --border: rgba(31, 27, 24, 0.1);
  --border-strong: rgba(31, 27, 24, 0.18);
  --shadow-sm: 0 2px 8px rgba(31, 27, 24, 0.06);
  --shadow-md: 0 10px 30px rgba(31, 27, 24, 0.1);
  --shadow-lg: 0 24px 60px rgba(31, 27, 24, 0.16);
  --radius-sm: 10px;
  --radius: 18px;
  --radius-lg: 28px;
  --radius-pill: 999px;
  --header-h: 72px;
  --maxw: 1180px;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
  --font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

[data-theme="dark"] {
  --primary: #ff5c3f;
  --primary-dark: #e8452c;
  --primary-light: #ff8a72;
  --accent: #ffc46b;
  --accent-2: #9d84ff;
  --bg: #121014;
  --bg-alt: #1a1720;
  --surface: rgba(34, 30, 40, 0.7);
  --surface-solid: #221e28;
  --text: #f3efe9;
  --text-soft: #c4bdb5;
  --text-muted: #8f877f;
  --border: rgba(255, 255, 255, 0.1);
  --border-strong: rgba(255, 255, 255, 0.2);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 10px 30px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 24px 60px rgba(0, 0, 0, 0.6);
}

*,
*::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: var(--font);
  font-size: 16px;
  line-height: 1.75;
  color: var(--text);
  background: var(--bg);
  background-image:
    radial-gradient(circle at 12% 8%, rgba(232, 69, 44, 0.08), transparent 42%),
    radial-gradient(circle at 88% 22%, rgba(124, 92, 255, 0.07), transparent 40%),
    radial-gradient(circle at 50% 100%, rgba(255, 179, 71, 0.06), transparent 50%);
  background-attachment: fixed;
  overflow-x: hidden;
  transition: background-color 0.35s var(--ease), color 0.35s var(--ease);
}

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

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

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

h1, h2, h3, h4, h5, h6 {
  margin: 0 0 0.6em;
  line-height: 1.3;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--text);
}

h1 { font-size: clamp(1.9rem, 4.2vw, 3.1rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2.1rem); }
h3 { font-size: clamp(1.15rem, 2vw, 1.4rem); }
h4 { font-size: 1.05rem; }

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

ul, ol {
  margin: 0 0 1.2em;
  padding-left: 1.4em;
  color: var(--text-soft);
}

li {
  margin-bottom: 0.5em;
}

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

blockquote {
  margin: 1.2em 0;
  padding: 1.1em 1.4em;
  border-left: 4px solid var(--primary);
  background: var(--surface);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-radius: 0 var(--radius) var(--radius) 0;
  box-shadow: var(--shadow-sm);
}

blockquote p {
  margin: 0;
  color: var(--text-soft);
  font-style: italic;
}

:focus-visible {
  outline: 2px solid var(--primary);
  outline-offset: 3px;
  border-radius: 4px;
}

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ============ Header ============ */
#site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--surface);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid var(--border);
  transition: background 0.35s var(--ease), box-shadow 0.35s var(--ease);
}

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

.header-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  min-height: var(--header-h);
  padding: 0 24px;
  display: flex;
  align-items: center;
  gap: 24px;
}

.brand-logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
  color: var(--text);
  font-weight: 800;
}

.brand-logo svg {
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  transition: transform 0.5s var(--ease);
}

.brand-logo:hover svg {
  transform: rotate(-8deg) scale(1.06);
}

.brand-name {
  font-size: 1.05rem;
  letter-spacing: -0.01em;
  white-space: nowrap;
}

#main-nav {
  flex: 1;
  min-width: 0;
}

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

#main-nav li {
  margin: 0;
}

#main-nav a {
  display: inline-block;
  padding: 7px 12px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-soft);
  border-radius: var(--radius-pill);
  transition: background 0.25s var(--ease), color 0.25s var(--ease), transform 0.25s var(--ease);
}

#main-nav a:hover,
#main-nav a:focus-visible {
  color: var(--primary);
  background: rgba(232, 69, 44, 0.1);
  transform: translateY(-1px);
}

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

.site-search {
  display: flex;
  align-items: center;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  overflow: hidden;
  transition: border-color 0.25s var(--ease), box-shadow 0.25s var(--ease);
}

.site-search:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(232, 69, 44, 0.15);
}

.site-search input {
  width: 180px;
  padding: 8px 6px 8px 16px;
  border: none;
  background: transparent;
  color: var(--text);
  font-family: inherit;
  font-size: 0.85rem;
  outline: none;
}

.site-search input::placeholder {
  color: var(--text-muted);
}

.site-search button {
  padding: 8px 16px;
  border: none;
  background: var(--primary);
  color: #fff;
  font-family: inherit;
  font-size: 0.85rem;
  font-weight: 700;
  cursor: pointer;
  transition: background 0.25s var(--ease);
}

.site-search button:hover {
  background: var(--primary-dark);
}

#theme-toggle,
#menu-toggle {
  padding: 8px 14px;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-pill);
  background: var(--bg-alt);
  color: var(--text-soft);
  font-family: inherit;
  font-size: 0.82rem;
  font-weight: 700;
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.25s var(--ease);
}

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

#menu-toggle {
  display: none;
}

/* ============ Breadcrumb ============ */
.breadcrumb {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 14px 24px 0;
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 0.82rem;
}

.breadcrumb li {
  margin: 0;
  color: var(--text-muted);
}

.breadcrumb li + li::before {
  content: "/";
  margin-right: 6px;
  color: var(--text-muted);
}

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

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

/* ============ Main layout ============ */
main {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px 40px;
}

main > section {
  margin-top: 56px;
  scroll-margin-top: calc(var(--header-h) + 20px);
}

main > section > h2 {
  position: relative;
  padding-bottom: 14px;
  margin-bottom: 24px;
}

main > section > h2::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 56px;
  height: 4px;
  border-radius: 4px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
}

/* ============ Banner ============ */
#banner {
  position: relative;
  margin-top: 24px;
  padding: 56px 40px 40px;
  border-radius: var(--radius-lg);
  overflow: hidden;
  color: #fff;
  background: linear-gradient(135deg, #e8452c 0%, #ff6b52 38%, #ff9a5a 62%, #7c5cff 100%);
  background-size: 200% 200%;
  animation: bannerShift 16s ease infinite;
  box-shadow: var(--shadow-lg);
}

#banner::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 82% 18%, rgba(255, 255, 255, 0.28), transparent 45%),
    radial-gradient(circle at 12% 88%, rgba(255, 255, 255, 0.16), transparent 40%);
  pointer-events: none;
}

#banner::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.06) 1px, transparent 1px);
  background-size: 42px 42px;
  mask-image: radial-gradient(circle at 70% 30%, #000 0%, transparent 72%);
  -webkit-mask-image: radial-gradient(circle at 70% 30%, #000 0%, transparent 72%);
  pointer-events: none;
}

@keyframes bannerShift {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

.banner-slide {
  position: relative;
  z-index: 1;
  max-width: 760px;
  animation: fadeUp 0.9s var(--ease) both;
}

.banner-slide[data-slide="2"] { animation-delay: 0.12s; }
.banner-slide[data-slide="3"] { animation-delay: 0.24s; }

.banner-slide + .banner-slide {
  margin-top: 20px;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.22);
}

.banner-slide h1,
.banner-slide h2 {
  color: #fff;
  text-shadow: 0 2px 18px rgba(0, 0, 0, 0.18);
}

.banner-slide h2 {
  font-size: clamp(1.25rem, 2.2vw, 1.6rem);
}

.banner-slide p {
  color: rgba(255, 255, 255, 0.94);
  font-size: 1.02rem;
  max-width: 68ch;
}

.banner-slide a {
  color: #fff;
  font-weight: 700;
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-underline-offset: 4px;
  transition: opacity 0.25s var(--ease);
}

.banner-slide a:hover {
  opacity: 0.8;
  color: #fff;
}

.banner-stats {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-top: 44px;
}

.banner-stats .stat {
  padding: 20px 18px;
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.14);
  border: 1px solid rgba(255, 255, 255, 0.28);
  backdrop-filter: blur(14px) saturate(160%);
  -webkit-backdrop-filter: blur(14px) saturate(160%);
  transition: transform 0.4s var(--ease), background 0.4s var(--ease);
}

.banner-stats .stat:hover {
  transform: translateY(-6px);
  background: rgba(255, 255, 255, 0.22);
}

.banner-stats .num {
  display: block;
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: #fff;
}

.banner-stats .num::after {
  content: "+";
  font-size: 0.6em;
  margin-left: 2px;
  opacity: 0.85;
}

.banner-stats .stat:last-child .num::after {
  content: "%";
}

.banner-stats .label {
  display: block;
  margin-top: 6px;
  font-size: 0.8rem;
  line-height: 1.45;
  color: rgba(255, 255, 255, 0.9);
}

/* ============ Cards: intro / product / service / solution ============ */
#intro,
#product,
#service,
#solution,
#scenarios,
#cases,
#news,
#articles,
#howto,
#faq,
#knowledge,
#notes,
#contact,
#sitemap {
  position: relative;
}

#intro {
  padding: 36px 32px;
  border-radius: var(--radius-lg);
  background: var(--surface);
  backdrop-filter: blur(18px) saturate(150%);
  -webkit-backdrop-filter: blur(18px) saturate(150%);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-md);
}

#intro h3 {
  margin-top: 1.6em;
  padding-left: 14px;
  border-left: 4px solid var(--primary);
}

#intro h3:first-of-type {
  margin-top: 0.8em;
}

#intro ul {
  display: grid;
  gap: 8px;
  padding-left: 0;
  list-style: none;
}

#intro ul li {
  position: relative;
  padding: 10px 16px 10px 40px;
  margin: 0;
  border-radius: var(--radius-sm);
  background: var(--bg-alt);
  border: 1px solid var(--border);
  transition: transform 0.3s var(--ease), border-color 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

#intro ul li::before {
  content: "";
  position: absolute;
  left: 16px;
  top: 50%;
  width: 10px;
  height: 10px;
  margin-top: -5px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
}

#intro ul li:hover {
  transform: translateX(4px);
  border-color: var(--primary);
  box-shadow: var(--shadow-sm);
}

/* Product articles */
#product > article {
  position: relative;
  margin-bottom: 20px;
  padding: 28px 30px;
  border-radius: var(--radius);
  background: var(--surface-solid);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease), border-color 0.4s var(--ease);
}

#product > article::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 6px;
  height: 100%;
  background: linear-gradient(180deg, var(--primary), var(--accent));
  opacity: 0.85;
  transition: width 0.4s var(--ease);
}

#product > article:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(232, 69, 44, 0.35);
}

#product > article:hover::before {
  width: 10px;
}

#product > article h3 {
  padding-left: 8px;
  color: var(--text);
}

#product > article h4 {
  display: inline-block;
  margin-top: 14px;
  padding: 3px 12px;
  font-size: 0.82rem;
  color: var(--primary);
  background: rgba(232, 69, 44, 0.1);
  border-radius: var(--radius-pill);
}

#product > article h4 + p {
  margin-top: 8px;
}

/* Service list */
#service ul {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
  padding-left: 0;
  list-style: none;
}

#service ul li {
  margin: 0;
  padding: 22px 24px;
  border-radius: var(--radius);
  background: var(--surface);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease), border-color 0.35s var(--ease);
}

#service ul li:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
}

#service ul li strong {
  display: block;
  margin-bottom: 6px;
  color: var(--primary);
  font-size: 1.02rem;
}

/* Solution cards */
#solution {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 18px;
  align-items: start;
}

#solution > h2 {
  grid-column: 1 / -1;
}

#solution > h3 {
  margin: 0;
  padding: 20px 22px 6px;
  border-radius: var(--radius) var(--radius) 0 0;
  background: var(--surface-solid);
  border: 1px solid var(--border);
  border-bottom: none;
  color: var(--text);
  font-size: 1.1rem;
  transition: color 0.3s var(--ease);
}

#solution > h3 + p {
  margin: 0;
  padding: 0 22px 22px;
  border-radius: 0 0 var(--radius) var(--radius);
  background: var(--surface-solid);
  border: 1px solid var(--border);
  border-top: none;
  box-shadow: var(--shadow-sm);
  transition: box-shadow 0.35s var(--ease), transform 0.35s var(--ease);
}

#solution > h3 + p:hover {
  box-shadow: var(--shadow-md);
}

#solution > h3 + p:hover,
#solution > h3:hover {
  color: var(--primary);
}

/* Scenarios */
#scenarios ul {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 14px;
  padding-left: 0;
  list-style: none;
}

#scenarios ul li {
  margin: 0;
  padding: 20px 22px 20px 52px;
  position: relative;
  border-radius: var(--radius);
  background: var(--bg-alt);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease), background 0.35s var(--ease);
}

#scenarios ul li::before {
  content: "";
  position: absolute;
  left: 20px;
  top: 24px;
  width: 14px;
  height: 14px;
  border-radius: 4px;
  background: linear-gradient(135deg, var(--primary), var(--accent-2));
  transform: rotate(45deg);
  transition: transform 0.4s var(--ease);
}

#scenarios ul li:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-md);
  background: var(--surface-solid);
}

#scenarios ul li:hover::before {
  transform: rotate(135deg);
}

#scenarios ul li strong {
  display: block;
  margin-bottom: 4px;
  color: var(--primary);
}

/* Cases */
#cases > article {
  margin-bottom: 18px;
  padding: 26px 28px;
  border-radius: var(--radius);
  background: var(--surface-solid);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease);
}

#cases > article:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

#cases > article h3 {
  color: var(--primary);
}

#cases > h3 {
  margin-top: 28px;
}

#cases blockquote {
  position: relative;
  margin: 14px 0;
  padding: 24px 26px 24px 56px;
  border-left: none;
  border-radius: var(--radius);
  background: linear-gradient(135deg, rgba(232, 69, 44, 0.08), rgba(124, 92, 255, 0.08));
  border: 1px solid var(--border);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

#cases blockquote::before {
  content: "“";
  position: absolute;
  left: 16px;
  top: 4px;
  font-size: 3.4rem;
  line-height: 1;
  font-family: Georgia, serif;
  color: var(--primary);
  opacity: 0.55;
}

#cases blockquote p {
  font-style: normal;
  color: var(--text-soft);
}

/* News */
#news ul {
  padding-left: 0;
  list-style: none;
  display: grid;
  gap: 16px;
}

#news ul li {
  margin: 0;
  padding: 24px 26px;
  border-radius: var(--radius);
  background: var(--surface);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  transition: transform 0.35s var(--ease), box-shadow 0.35s var(--ease), border-color 0.35s var(--ease);
}

#news ul li:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
}

#news ul li h3 {
  margin-bottom: 6px;
}

#news ul li h3 a {
  color: var(--text);
  transition: color 0.25s var(--ease);
}

#news ul li h3 a:hover {
  color: var(--primary);
}

#news ul li p {
  margin-bottom: 4px;
  font-size: 0.92rem;
}

#news ul li p:first-of-type {
  color: var(--text-muted);
  font-size: 0.82rem;
}

/* Articles */
#articles > article {
  position: relative;
  margin-bottom: 18px;
  padding: 26px 28px;
  border-radius: var(--radius);
  background: var(--surface-solid);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease), border-color 0.4s var(--ease);
}

#articles > article::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 120px;
  height: 120px;
  background: radial-gradient(circle at top right, rgba(232, 69, 44, 0.12), transparent 70%);
  pointer-events: none;
  transition: transform 0.5s var(--ease);
}

#articles > article:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(232, 69, 44, 0.35);
}

#articles > article:hover::after {
  transform: scale(1.4);
}

#articles > article h3 {
  margin-bottom: 8px;
}

#articles > article h3 a {
  color: var(--text);
  transition: color 0.25s var(--ease);
}

#articles > article h3 a:hover {
  color: var(--primary);
}

#articles > article p {
  font-size: 0.94rem;
}

#articles > article p:first-of-type {
  display: inline-block;
  padding: 2px 12px;
  margin-bottom: 10px;
  font-size: 0.78rem;
  color: var(--text-muted);
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
}

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

#articles > article p:last-child a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-weight: 700;
  font-size: 0.9rem;
}

#articles > article p:last-child a::after {
  content: "→";
  transition: transform 0.3s var(--ease);
}

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

/* HowTo */
#howto {
  padding: 36px 32px;
  border-radius: var(--radius-lg);
  background: var(--surface);
  backdrop-filter: blur(18px) saturate(150%);
  -webkit-backdrop-filter: blur(18px) saturate(150%);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-md);
}

#howto h3 {
  margin-top: 1.5em;
  padding-left: 14px;
  border-left: 4px solid var(--primary);
}

#howto h3:first-of-type {
  margin-top: 0.6em;
}

#howto ol {
  counter-reset: step;
  padding-left: 0;
  list-style: none;
  display: grid;
  gap: 12px;
}

#howto ol li {
  position: relative;
  margin: 0;
  padding: 16px 20px 16px 62px;
  border-radius: var(--radius-sm);
  background: var(--bg-alt);
  border: 1px solid var(--border);
  counter-increment: step;
  transition: transform 0.3s var(--ease), border-color 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

#howto ol li::before {
  content: counter(step);
  position: absolute;
  left: 16px;
  top: 50%;
  transform: translateY(-50%);
  width: 32px;
  height: 32px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  font-weight: 800;
  font-size: 0.9rem;
  box-shadow: 0 4px 12px rgba(232, 69, 44, 0.3);
}

#howto ol li:hover {
  transform: translateX(6px);
  border-color: var(--primary);
  box-shadow: var(--shadow-sm);
}

#howto ul {
  display: grid;
  gap: 8px;
  padding-left: 0;
  list-style: none;
}

#howto ul li {
  position: relative;
  margin: 0;
  padding: 10px 16px 10px 38px;
  border-radius: var(--radius-sm);
  background: var(--bg-alt);
  border: 1px solid var(--border);
}

#howto ul li::before {
  content: "✓";
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--primary);
  font-weight: 900;
}

/* FAQ */
#faq details {
  margin-bottom: 12px;
  border-radius: var(--radius);
  background: var(--surface-solid);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  transition: box-shadow 0.35s var(--ease), border-color 0.35s var(--ease);
}

#faq details:hover {
  border-color: rgba(232, 69, 44, 0.4);
  box-shadow: var(--shadow-md);
}

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

#faq summary {
  position: relative;
  padding: 18px 56px 18px 22px;
  font-weight: 700;
  font-size: 1rem;
  color: var(--text);
  cursor: pointer;
  list-style: none;
  transition: color 0.25s var(--ease), background 0.25s var(--ease);
}

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

#faq summary::after {
  content: "+";
  position: absolute;
  right: 20px;
  top: 50%;
  transform: translateY(-50%);
  width: 26px;
  height: 26px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: rgba(232, 69, 44, 0.1);
  color: var(--primary);
  font-size: 1.2rem;
  font-weight: 700;
  line-height: 1;
  transition: transform 0.35s var(--ease), background 0.35s var(--ease);
}

#faq details[open] summary {
  color: var(--primary);
  background: rgba(232, 69, 44, 0.06);
}

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

#faq details > p {
  margin: 0;
  padding: 4px 22px 22px;
  font-size: 0.95rem;
  animation: fadeUp 0.4s var(--ease) both;
}

/* Knowledge */
#knowledge h3 {
  margin-top: 1.4em;
  padding-left: 14px;
  border-left: 4px solid var(--accent-2);
}

#knowledge h3:first-of-type {
  margin-top: 0.4em;
}

/* Notes */
#notes ul {
  display: grid;
  gap: 10px;
  padding: 24px 26px;
  list-style: none;
  border-radius: var(--radius);
  background: linear-gradient(135deg, rgba(255, 179, 71, 0.12), rgba(232, 69, 44, 0.08));
  border: 1px solid rgba(232, 69, 44, 0.25);
}

#notes ul li {
  position: relative;
  margin: 0;
  padding-left: 30px;
}

#notes ul li::before {
  content: "!";
  position: absolute;
  left: 0;
  top: 2px;
  width: 20px;
  height: 20px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  font-size: 0.72rem;
  font-weight: 900;
}

/* Contact */
#contact {
  padding: 36px 32px;
  border-radius: var(--radius-lg);
  background: var(--surface);
  backdrop-filter: blur(18px) saturate(150%);
  -webkit-backdrop-filter: blur(18px) saturate(150%);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-md);
}

#contact ul {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 12px;
  padding-left: 0;
  list-style: none;
}

#contact ul li {
  margin: 0;
  padding: 16px 18px;
  border-radius: var(--radius-sm);
  background: var(--bg-alt);
  border: 1px solid var(--border);
  font-size: 0.94rem;
  transition: transform 0.3s var(--ease), border-color 0.3s var(--ease);
}

#contact ul li:hover {
  transform: translateY(-3px);
  border-color: var(--primary);
}

#contact h3 {
  margin-top: 1.6em;
  padding-left: 14px;
  border-left: 4px solid var(--primary);
}

/* Sitemap */
#sitemap ul {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding-left: 0;
  list-style: none;
}

#sitemap ul li {
  margin: 0;
}

#sitemap ul li a {
  display: inline-block;
  padding: 7px 16px;
  border-radius: var(--radius-pill);
  background: var(--bg-alt);
  border: 1px solid var(--border);
  color: var(--text-soft);
  font-size: 0.88rem;
  font-weight: 600;
  transition: all 0.25s var(--ease);
}

#sitemap ul li a:hover {
  color: #fff;
  background: var(--primary);
  border-color: var(--primary);
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(232, 69, 44, 0.3);
}

#sitemap h3 {
  margin-top: 1.6em;
}

/* ============ Footer ============ */
#site-footer {
  margin-top: 56px;
  padding: 56px 24px 32px;
  background: linear-gradient(180deg, var(--bg-alt), var(--bg));
  border-top: 1px solid var(--border);
}

#site-footer > section {
  max-width: var(--maxw);
  margin: 0 auto 32px;
}

#site-footer h2 {
  font-size: 1.05rem;
  margin-bottom: 12px;
  color: var(--text);
}

#site-footer h3 {
  font-size: 0.95rem;
  margin: 16px 0 6px;
  color: var(--text-soft);
}

#site-footer p {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 8px;
}

#site-footer a {
  color: var(--primary);
}

.copyright {
  max-width: var(--maxw);
  margin: 0 auto;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  text-align: center;
  font-size: 0.82rem !important;
  color: var(--text-muted) !important;
}

/* ============ Back to top ============ */
#back-to-top {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 900;
  padding: 12px 18px;
  border: none;
  border-radius: var(--radius-pill);
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  color: #fff;
  font-family: inherit;
  font-size: 0.85rem;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 10px 26px rgba(232, 69, 44, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px);
  transition: opacity 0.35s var(--ease), transform 0.35s var(--ease), visibility 0.35s;
}

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

#back-to-top:hover {
  transform: translateY(-4px);
  box-shadow: 0 16px 34px rgba(232, 69, 44, 0.5);
}

/* ============ Scroll animations ============ */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}

.reveal.in-view {
  opacity: 1;
  transform: translateY(0);
}

@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(22px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  .reveal {
    opacity: 1;
    transform: none;
  }
}

/* ============ Responsive ============ */
@media (max-width: 1080px) {
  .site-search input {
    width: 130px;
  }
  #main-nav a {
    padding: 7px 9px;
    font-size: 0.85rem;
  }
}

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

  .header-inner {
    flex-wrap: wrap;
    padding: 10px 18px;
    gap: 12px;
  }

  .brand-name {
    font-size: 0.98rem;
  }

  #menu-toggle {
    display: inline-block;
  }

  #main-nav {
    order: 3;
    flex-basis: 100%;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.45s var(--ease);
  }

  #main-nav.open {
    max-height: 520px;
  }

  #main-nav ul {
    flex-direction: column;
    gap: 2px;
    padding: 8px 0 12px;
    border-top: 1px solid var(--border);
  }

  #main-nav a {
    display: block;
    padding: 11px 14px;
    font-size: 0.95rem;
    border-radius: var(--radius-sm);
  }

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

  .site-search {
    display: none;
  }

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

  #banner {
    padding: 40px 24px 32px;
  }

  main {
    padding: 0 18px 32px;
  }

  main > section {
    margin-top: 44px;
  }

  #intro,
  #howto,
  #contact {
    padding: 28px 22px;
  }

  #product > article,
  #cases > article,
  #articles > article,
  #news ul li {
    padding: 22px 20px;
  }

  #solution {
    grid-template-columns: 1fr;
  }

  .breadcrumb {
    padding: 12px 18px 0;
  }
}

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

  .brand-name {
    display: none;
  }

  .banner-stats {
    grid-template-columns: 1fr 1fr;
    gap: 10px;
    margin-top: 32px;
  }

  .banner-stats .stat {
    padding: 14px 12px;
  }

  .banner-stats .label {
    font-size: 0.72rem;
  }

  #banner {
    border-radius: var(--radius);
    padding: 32px 18px 26px;
  }

  main {
    padding: 0 14px 28px;
  }

  main > section {
    margin-top: 36px;
  }

  #intro,
  #howto,
  #contact {
    padding: 22px 16px;
    border-radius: var(--radius);
  }

  #product > article,
  #cases > article,
  #articles > article,
  #news ul li {
    padding: 18px 16px;
    border-radius: var(--radius-sm);
  }

  #product > article::before {
    width: 4px;
  }

  #faq summary {
    padding: 15px 48px 15px 16px;
    font-size: 0.94rem;
  }

  #faq details > p {
    padding: 2px 16px 18px;
    font-size: 0.9rem;
  }

  #howto ol li {
    padding: 14px 14px 14px 54px;
  }

  #howto ol li::before {
    left: 12px;
    width: 28px;
    height: 28px;
  }

  #cases blockquote {
    padding: 20px 18px 20px 46px;
  }

  #service ul,
  #scenarios ul,
  #contact ul {
    grid-template-columns: 1fr;
  }

  #back-to-top {
    right: 14px;
    bottom: 14px;
    padding: 10px 14px;
    font-size: 0.78rem;
  }

  #site-footer {
    padding: 40px 16px 24px;
  }

  .copyright {
    font-size: 0.76rem !important;
  }
}

@media (hover: none) {
  #product > article:hover,
  #service ul li:hover,
  #cases > article:hover,
  #articles > article:hover,
  #news ul li:hover,
  #scenarios ul li:hover {
    transform: none;
  }
}