:root {
  --primary: #e8748a;
  --primary-light: #f7b7c6;
  --primary-dark: #c95570;
  --primary-soft: #fdeef2;
  --accent: #7c5cbf;
  --accent-soft: #f0ebfa;
  --warm: #f5a623;
  --bg: #fff9fb;
  --bg-alt: #fff1f5;
  --surface: #ffffff;
  --surface-glass: rgba(255, 255, 255, 0.72);
  --surface-glass-border: rgba(255, 255, 255, 0.55);
  --text: #33242b;
  --text-secondary: #6b5560;
  --text-muted: #9a8890;
  --border: #f0dce4;
  --shadow-sm: 0 2px 8px rgba(232, 116, 138, 0.08);
  --shadow-md: 0 8px 28px rgba(232, 116, 138, 0.12);
  --shadow-lg: 0 16px 48px rgba(232, 116, 138, 0.16);
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --transition: 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
  --max-width: 1200px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --primary: #f08ca0;
    --primary-light: #d47a8e;
    --primary-dark: #ff9fb2;
    --primary-soft: #2a1a20;
    --accent: #9b7fd4;
    --accent-soft: #1e1828;
    --warm: #f5b84d;
    --bg: #1a1216;
    --bg-alt: #221820;
    --surface: #2a1e24;
    --surface-glass: rgba(42, 30, 36, 0.78);
    --surface-glass-border: rgba(255, 255, 255, 0.08);
    --text: #f0e6ea;
    --text-secondary: #c4aeb8;
    --text-muted: #8a7680;
    --border: #3d2a34;
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.2);
    --shadow-md: 0 8px 28px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.4);
  }
}

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

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

body {
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.75;
  color: var(--text);
  background-color: var(--bg);
  background-image:
    radial-gradient(ellipse 80% 50% at 50% -10%, rgba(232, 116, 138, 0.08), transparent),
    radial-gradient(ellipse 60% 40% at 100% 100%, rgba(124, 92, 191, 0.06), transparent);
  background-attachment: fixed;
  min-height: 100vh;
  overflow-x: hidden;
  transition: background-color var(--transition), color var(--transition);
}

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

ul,
ol {
  list-style: none;
}

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

h1 {
  font-size: clamp(1.75rem, 4vw, 2.75rem);
}

h2 {
  font-size: clamp(1.4rem, 3vw, 2rem);
}

h3 {
  font-size: clamp(1.1rem, 2.2vw, 1.35rem);
}

p {
  color: var(--text-secondary);
}

::selection {
  background: var(--primary);
  color: #fff;
}

::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

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

::-webkit-scrollbar-thumb {
  background: var(--primary-light);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--primary);
}

/* ========== HEADER ========== */

header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--surface-glass);
  backdrop-filter: blur(20px) saturate(1.4);
  -webkit-backdrop-filter: blur(20px) saturate(1.4);
  border-bottom: 1px solid var(--surface-glass-border);
  box-shadow: var(--shadow-sm);
  transition: background var(--transition), box-shadow var(--transition);
}

header > div {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0.75rem 1.5rem;
  display: flex;
  align-items: center;
  gap: 1.5rem;
  flex-wrap: wrap;
}

header > div > a:first-child {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--text);
  flex-shrink: 0;
  transition: transform var(--transition);
}

header > div > a:first-child:hover {
  transform: scale(1.03);
}

header > div > a:first-child svg {
  width: 40px;
  height: 40px;
  filter: drop-shadow(0 2px 6px rgba(232, 116, 138, 0.3));
  transition: transform var(--transition);
}

header > div > a:first-child:hover svg {
  transform: rotate(-8deg) scale(1.08);
}

header > div > a:first-child span {
  background: linear-gradient(135deg, var(--primary), var(--accent));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

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

header nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
}

header nav ul li a {
  display: block;
  padding: 0.45rem 0.85rem;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  white-space: nowrap;
  position: relative;
  transition: color var(--transition), background var(--transition);
}

header nav ul li a::after {
  content: "";
  position: absolute;
  bottom: 4px;
  left: 50%;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  border-radius: 2px;
  transform: translateX(-50%);
  transition: width var(--transition);
}

header nav ul li a:hover {
  color: var(--primary);
  background: var(--primary-soft);
}

header nav ul li a:hover::after {
  width: 60%;
}

header form[role="search"] {
  display: flex;
  align-items: center;
  gap: 0;
  flex-shrink: 0;
  position: relative;
}

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"] {
  width: 180px;
  padding: 0.55rem 0.9rem;
  font-size: 0.875rem;
  font-family: var(--font);
  color: var(--text);
  background: var(--bg-alt);
  border: 1.5px solid transparent;
  border-radius: var(--radius-sm) 0 0 var(--radius-sm);
  outline: none;
  transition: width var(--transition), border-color var(--transition), background var(--transition), box-shadow var(--transition);
}

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

header form[role="search"] input[type="search"]:focus {
  width: 240px;
  border-color: var(--primary);
  background: var(--surface);
  box-shadow: 0 0 0 3px rgba(232, 116, 138, 0.12);
}

header form[role="search"] button {
  padding: 0.55rem 1rem;
  font-size: 0.875rem;
  font-family: var(--font);
  font-weight: 600;
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  border: none;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  cursor: pointer;
  white-space: nowrap;
  transition: opacity var(--transition), transform var(--transition), box-shadow var(--transition);
}

header form[role="search"] button:hover {
  opacity: 0.9;
  box-shadow: 0 4px 12px rgba(232, 116, 138, 0.35);
}

header form[role="search"] button:active {
  transform: scale(0.97);
}

/* ========== MAIN LAYOUT ========== */

main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem 3rem;
}

main > section {
  margin-top: 2.5rem;
  padding: 2rem;
  background: var(--surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
  transition: box-shadow var(--transition), transform var(--transition), background var(--transition), border-color var(--transition);
  animation: fadeInUp 0.7s ease both;
}

main > section:hover {
  box-shadow: var(--shadow-md);
}

main > section > h2 {
  margin-bottom: 1.25rem;
  padding-bottom: 0.75rem;
  position: relative;
  display: inline-block;
}

main > section > h2::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent), transparent);
  border-radius: 3px;
}

main > section > h3 {
  margin-top: 1.5rem;
  margin-bottom: 0.6rem;
  color: var(--primary-dark);
  position: relative;
  padding-left: 0.85rem;
}

main > section > h3::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.2em;
  bottom: 0.2em;
  width: 4px;
  background: linear-gradient(180deg, var(--primary), var(--accent));
  border-radius: 4px;
}

main > section > p {
  margin-bottom: 0.9rem;
}

/* ========== HERO ========== */

#hero {
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, #fdeef2 0%, #f0ebfa 50%, #fdeef2 100%);
  border: none;
  padding: 3rem 2rem;
  margin-top: 1.5rem;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
}

#hero::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -20%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(232, 116, 138, 0.15), transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

#hero::after {
  content: "";
  position: absolute;
  bottom: -40%;
  left: -10%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(124, 92, 191, 0.1), transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

@media (prefers-color-scheme: dark) {
  #hero {
    background: linear-gradient(135deg, #2a1a20 0%, #1e1828 50%, #2a1a20 100%);
  }
}

#hero h1 {
  position: relative;
  z-index: 1;
  margin-bottom: 1.25rem;
  background: linear-gradient(135deg, var(--primary-dark), var(--accent));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

#hero > p {
  position: relative;
  z-index: 1;
  max-width: 800px;
  font-size: 1rem;
  line-height: 1.85;
  margin-bottom: 1rem;
}

#hero > div:last-of-type {
  position: relative;
  z-index: 1;
  margin-top: 2rem;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

#hero > div:last-of-type svg {
  width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius-lg);
  transition: transform 0.6s cubic-bezier(0.25, 0.8, 0.25, 1);
}

#hero > div:last-of-type:hover svg {
  transform: scale(1.03);
}

#hero > div:last-of-type span {
  display: inline-block;
  margin-top: 0.75rem;
  padding: 0.3rem 0.9rem;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--primary-dark);
  background: var(--surface-glass);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-radius: 999px;
  border: 1px solid var(--surface-glass-border);
}

/* ========== BREADCRUMB ========== */

nav[aria-label="面包屑导航"] {
  margin-top: 1.5rem;
  padding: 0.75rem 1.25rem;
  background: var(--surface-glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-radius: var(--radius-md);
  border: 1px solid var(--surface-glass-border);
  box-shadow: var(--shadow-sm);
}

nav[aria-label="面包屑导航"] ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.25rem;
  font-size: 0.875rem;
}

nav[aria-label="面包屑导航"] ol li {
  display: flex;
  align-items: center;
  color: var(--text-muted);
}

nav[aria-label="面包屑导航"] ol li:not(:last-child)::after {
  content: "›";
  margin: 0 0.5rem;
  color: var(--text-muted);
  font-size: 1.1em;
  line-height: 1;
}

nav[aria-label="面包屑导航"] ol li a {
  color: var(--text-secondary);
  font-weight: 500;
  transition: color var(--transition);
}

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

nav[aria-label="面包屑导航"] ol li:last-child {
  color: var(--primary);
  font-weight: 600;
}

/* ========== PRODUCTS / SOLUTIONS LISTS ========== */

#products ul,
#solutions ul,
#howto ul,
#howto ol {
  margin: 0.75rem 0;
  padding-left: 0;
}

#products ul li,
#solutions ul li,
#howto ul li {
  position: relative;
  padding: 0.5rem 0 0.5rem 1.75rem;
  color: var(--text-secondary);
  transition: color var(--transition), transform var(--transition);
}

#products ul li::before,
#solutions ul li::before,
#howto ul li::before {
  content: "";
  position: absolute;
  left: 0.35rem;
  top: 1.05rem;
  width: 8px;
  height: 8px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 50%;
  box-shadow: 0 0 0 3px rgba(232, 116, 138, 0.12);
}

#products ul li:hover,
#solutions ul li:hover,
#howto ul li:hover {
  color: var(--text);
  transform: translateX(4px);
}

#howto ol {
  counter-reset: howto-step;
  list-style: none;
}

#howto ol li {
  position: relative;
  padding: 0.75rem 0 0.75rem 3rem;
  counter-increment: howto-step;
  color: var(--text-secondary);
  transition: color var(--transition), transform var(--transition);
}

#howto ol li::before {
  content: counter(howto-step);
  position: absolute;
  left: 0;
  top: 0.65rem;
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  font-weight: 700;
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 50%;
  box-shadow: 0 3px 10px rgba(232, 116, 138, 0.3);
}

#howto ol li:hover {
  color: var(--text);
  transform: translateX(4px);
}

/* ========== CASES / BLOCKQUOTE ========== */

#cases blockquote {
  margin: 1rem 0;
  padding: 1.25rem 1.5rem;
  background: linear-gradient(135deg, var(--primary-soft), var(--accent-soft));
  border-left: 4px solid var(--primary);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  position: relative;
  transition: transform var(--transition), box-shadow var(--transition);
}

#cases blockquote::before {
  content: "\201C";
  position: absolute;
  top: -0.25rem;
  left: 0.75rem;
  font-size: 3rem;
  line-height: 1;
  color: var(--primary);
  opacity: 0.25;
  font-family: Georgia, serif;
}

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

#cases blockquote p {
  font-style: italic;
  color: var(--text-secondary);
  position: relative;
  z-index: 1;
}

/* ========== NEWS ========== */

#news h3 {
  margin-top: 1.25rem;
}

#news h3 + p {
  padding-left: 0.85rem;
}

/* ========== ARTICLES ========== */

#articles {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.25rem;
}

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

#articles article {
  padding: 1.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition), background var(--transition);
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
}

#articles article::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition);
}

#articles article:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary-light);
}

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

#articles article h3 {
  margin-top: 0;
  margin-bottom: 0.5rem;
  padding-left: 0;
  font-size: 1.1rem;
  color: var(--text);
  transition: color var(--transition);
}

#articles article h3::before {
  display: none;
}

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

#articles article > p:first-of-type {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 0.6rem;
}

#articles article > p:nth-of-type(2) {
  flex: 1;
  font-size: 0.9rem;
  line-height: 1.7;
  margin-bottom: 1rem;
}

#articles article a {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--primary);
  align-self: flex-start;
  padding: 0.4rem 0.9rem;
  background: var(--primary-soft);
  border-radius: 999px;
  transition: background var(--transition), color var(--transition), transform var(--transition), box-shadow var(--transition);
}

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

#articles article a:hover {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: #fff;
  transform: translateX(2px);
  box-shadow: 0 4px 12px rgba(232, 116, 138, 0.3);
}

#articles article a:hover::after {
  transform: translateX(3px);
}

/* ========== FAQ ========== */

#faq details {
  margin-bottom: 0.75rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color var(--transition), box-shadow var(--transition), background var(--transition);
}

#faq details:hover {
  border-color: var(--primary-light);
  box-shadow: var(--shadow-sm);
}

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

#faq details summary {
  padding: 1rem 1.25rem;
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  transition: color var(--transition), background var(--transition);
  position: relative;
  user-select: none;
}

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

#faq details summary::before {
  content: "";
  flex-shrink: 0;
  width: 22px;
  height: 22px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-radius: 50%;
  position: relative;
  transition: transform var(--transition);
}

#faq details summary::after {
  content: "";
  position: absolute;
  left: calc(1.25rem + 7px);
  top: 50%;
  width: 8px;
  height: 2px;
  background: #fff;
  border-radius: 2px;
  transform: translateY(-50%);
  transition: transform var(--transition);
}

#faq details summary::before,
#faq details summary::after {
  pointer-events: none;
}

#faq details summary:hover {
  color: var(--primary);
  background: var(--primary-soft);
}

#faq details[open] summary {
  color: var(--primary-dark);
  border-bottom: 1px solid var(--border);
}

#faq details[open] summary::before {
  transform: rotate(90deg);
}

#faq details[open] summary::after {
  transform: translateY(-50%) rotate(90deg);
}

#faq details p {
  padding: 1rem 1.25rem 1.25rem;
  font-size: 0.9rem;
  line-height: 1.8;
  color: var(--text-secondary);
  animation: fadeIn 0.3s ease;
}

/* ========== CONTACT ========== */

#contact p {
  padding: 0.35rem 0;
  font-size: 0.95rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
}

#contact p:first-of-type,
#contact p:nth-of-type(2) {
  font-weight: 600;
  color: var(--text);
}

#contact a {
  word-break: break-all;
}

/* ========== SITEMAP & LINKS ========== */

#sitemap ul,
#links ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

#sitemap ul li a,
#links ul li a {
  display: inline-block;
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: 999px;
  transition: all var(--transition);
}

#sitemap ul li a:hover,
#links ul li a:hover {
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border-color: transparent;
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(232, 116, 138, 0.3);
}

/* ========== LEGAL ========== */

#legal h3 {
  margin-top: 1.25rem;
}

/* ========== FOOTER ========== */

footer {
  margin-top: 3rem;
  padding: 2.5rem 1.5rem;
  background: linear-gradient(135deg, var(--primary-soft), var(--accent-soft));
  border-top: 1px solid var(--border);
  text-align: center;
  position: relative;
  overflow: hidden;
}

footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary), var(--accent), var(--warm), var(--primary));
  background-size: 200% 100%;
  animation: gradientShift 6s linear infinite;
}

footer p {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
  line-height: 1.7;
}

footer p:first-of-type {
  font-weight: 600;
  color: var(--text-secondary);
}

footer p a {
  color: var(--text-secondary);
  font-weight: 500;
  transition: color var(--transition);
}

footer p a:hover {
  color: var(--primary);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* ========== BACK TO TOP ========== */

body > button[type="button"][aria-label="返回顶部"] {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  z-index: 900;
  width: 46px;
  height: 46px;
  padding: 0;
  font-size: 0;
  color: transparent;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  border: none;
  border-radius: 50%;
  cursor: pointer;
  box-shadow: 0 6px 20px rgba(232, 116, 138, 0.4);
  transition: transform var(--transition), box-shadow var(--transition), opacity var(--transition);
  overflow: hidden;
}

body > button[type="button"][aria-label="返回顶部"]::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 10px;
  height: 10px;
  border-top: 2.5px solid #fff;
  border-left: 2.5px solid #fff;
  transform: translate(-50%, -30%) rotate(45deg);
  transition: transform var(--transition);
}

body > button[type="button"][aria-label="返回顶部"]:hover {
  transform: translateY(-4px) scale(1.08);
  box-shadow: 0 10px 28px rgba(232, 116, 138, 0.55);
}

body > button[type="button"][aria-label="返回顶部"]:hover::before {
  transform: translate(-50%, -40%) rotate(45deg);
}

body > button[type="button"][aria-label="返回顶部"]:active {
  transform: translateY(-1px) scale(0.98);
}

/* ========== ANIMATIONS ========== */

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes gradientShift {
  0% {
    background-position: 0% 50%;
  }
  100% {
    background-position: 200% 50%;
  }
}

@keyframes pulseGlow {
  0%, 100% {
    box-shadow: 0 0 0 0 rgba(232, 116, 138, 0.3);
  }
  50% {
    box-shadow: 0 0 0 8px rgba(232, 116, 138, 0);
  }
}

/* ========== SCROLL REVEAL (progressive enhancement) ========== */

@media (prefers-reduced-motion: no-preference) {
  main > section {
    animation: fadeInUp 0.7s cubic-bezier(0.25, 0.8, 0.25, 1) both;
  }

  main > section:nth-child(1) { animation-delay: 0.05s; }
  main > section:nth-child(2) { animation-delay: 0.1s; }
  main > section:nth-child(3) { animation-delay: 0.15s; }
  main > section:nth-child(4) { animation-delay: 0.2s; }
  main > section:nth-child(5) { animation-delay: 0.25s; }
  main > section:nth-child(6) { animation-delay: 0.3s; }
  main > section:nth-child(7) { animation-delay: 0.35s; }
  main > section:nth-child(8) { animation-delay: 0.4s; }
  main > section:nth-child(9) { animation-delay: 0.45s; }
  main > section:nth-child(10) { animation-delay: 0.5s; }
  main > section:nth-child(11) { animation-delay: 0.55s; }
  main > section:nth-child(12) { animation-delay: 0.6s; }
  main > section:nth-child(13) { animation-delay: 0.65s; }
  main > section:nth-child(14) { animation-delay: 0.7s; }
  main > section:nth-child(15) { animation-delay: 0.75s; }
  main > section:nth-child(16) { animation-delay: 0.8s; }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* ========== RESPONSIVE: TABLET ========== */

@media (max-width: 1024px) {
  header > div {
    gap: 1rem;
    padding: 0.75rem 1.25rem;
  }

  header nav ul li a {
    padding: 0.4rem 0.65rem;
    font-size: 0.85rem;
  }

  header form[role="search"] input[type="search"] {
    width: 140px;
  }

  header form[role="search"] input[type="search"]:focus {
    width: 180px;
  }

  main {
    padding: 0 1.25rem 2.5rem;
  }

  main > section {
    padding: 1.75rem;
  }

  #articles {
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  }
}

/* ========== RESPONSIVE: MOBILE ========== */

@media (max-width: 768px) {
  body {
    font-size: 15px;
  }

  header > div {
    flex-direction: column;
    align-items: stretch;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
  }

  header > div > a:first-child {
    justify-content: center;
  }

  header nav {
    order: 3;
    width: 100%;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }

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

  header nav ul {
    flex-wrap: nowrap;
    justify-content: flex-start;
    gap: 0.15rem;
    padding-bottom: 0.25rem;
  }

  header nav ul li a {
    padding: 0.45rem 0.7rem;
    font-size: 0.82rem;
  }

  header form[role="search"] {
    order: 2;
    width: 100%;
  }

  header form[role="search"] input[type="search"] {
    flex: 1;
    width: auto;
    min-width: 0;
  }

  header form[role="search"] input[type="search"]:focus {
    width: auto;
  }

  main {
    padding: 0 0.875rem 2rem;
  }

  main > section {
    margin-top: 1.5rem;
    padding: 1.25rem;
    border-radius: var(--radius-md);
  }

  main > section > h2 {
    font-size: 1.25rem;
  }

  main > section > h3 {
    font-size: 1.05rem;
  }

  #hero {
    padding: 1.75rem 1.25rem;
    border-radius: var(--radius-lg);
  }

  #hero h1 {
    font-size: 1.5rem;
  }

  #hero > p {
    font-size: 0.9rem;
  }

  #hero > div:last-of-type svg {
    border-radius: var(--radius-md);
  }

  nav[aria-label="面包屑导航"] {
    padding: 0.6rem 0.9rem;
    font-size: 0.8rem;
  }

  #articles {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  #articles article {
    padding: 1.25rem;
  }

  #faq details summary {
    padding: 0.85rem 1rem;
    font-size: 0.88rem;
    gap: 0.6rem;
  }

  #faq details summary::after {
    left: calc(1rem + 7px);
  }

  #faq details p {
    padding: 0.85rem 1rem 1rem;
    font-size: 0.85rem;
  }

  #contact p {
    font-size: 0.88rem;
  }

  #sitemap ul li a,
  #links ul li a {
    padding: 0.4rem 0.8rem;
    font-size: 0.8rem;
  }

  footer {
    padding: 2rem 1rem;
  }

  footer p {
    font-size: 0.78rem;
  }

  body > button[type="button"][aria-label="返回顶部"] {
    bottom: 1rem;
    right: 1rem;
    width: 42px;
    height: 42px;
  }
}

/* ========== RESPONSIVE: SMALL MOBILE ========== */

@media (max-width: 380px) {
  header > div > a:first-child {
    font-size: 1.1rem;
  }

  header > div > a:first-child svg {
    width: 34px;
    height: 34px;
  }

  #hero h1 {
    font-size: 1.3rem;
  }

  main > section {
    padding: 1rem;
  }

  #howto ol li {
    padding-left: 2.5rem;
  }

  #howto ol li::before {
    width: 24px;
    height: 24px;
    font-size: 0.72rem;
  }
}

/* ========== PRINT ========== */

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

  body {
    background: #fff;
    color: #000;
    font-size: 12pt;
  }

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

  a {
    color: #000;
    text-decoration: underline;
  }

  #faq details {
    border: 1px solid #ccc;
  }

  #faq details p {
    display: block;
  }
}