:root {
  --panda-bg: #f5f6fa;
  --panda-bg-alt: #ffffff;
  --panda-surface: rgba(255, 255, 255, 0.72);
  --panda-surface-solid: #ffffff;
  --panda-border: rgba(26, 26, 46, 0.1);
  --panda-text: #1a1a2e;
  --panda-text-soft: #4a4e69;
  --panda-text-muted: #6c7085;
  --panda-primary: #e94560;
  --panda-primary-dark: #c2314a;
  --panda-primary-soft: rgba(233, 69, 96, 0.1);
  --panda-accent: #0f3460;
  --panda-accent-soft: rgba(15, 52, 96, 0.08);
  --panda-deep: #16213e;
  --panda-shadow-sm: 0 2px 8px rgba(26, 26, 46, 0.06);
  --panda-shadow-md: 0 8px 24px rgba(26, 26, 46, 0.1);
  --panda-shadow-lg: 0 16px 48px rgba(26, 26, 46, 0.16);
  --panda-radius-sm: 10px;
  --panda-radius-md: 16px;
  --panda-radius-lg: 24px;
  --panda-radius-pill: 999px;
  --panda-glass-blur: blur(16px);
  --panda-transition: 0.28s cubic-bezier(0.22, 0.61, 0.36, 1);
  --panda-gradient-hero: linear-gradient(135deg, #1a1a2e 0%, #16213e 38%, #0f3460 72%, #e94560 130%);
  --panda-gradient-primary: linear-gradient(135deg, #e94560 0%, #c2314a 100%);
  --panda-gradient-soft: linear-gradient(135deg, rgba(233, 69, 96, 0.12) 0%, rgba(15, 52, 96, 0.12) 100%);
  --panda-font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  scroll-padding-top: 96px;
}

body {
  margin: 0;
  font-family: var(--panda-font);
  font-size: 16px;
  line-height: 1.75;
  color: var(--panda-text);
  background-color: var(--panda-bg);
  background-image:
    radial-gradient(circle at 12% 8%, rgba(233, 69, 96, 0.08) 0%, transparent 42%),
    radial-gradient(circle at 88% 4%, rgba(15, 52, 96, 0.1) 0%, transparent 46%),
    radial-gradient(circle at 50% 100%, rgba(22, 33, 62, 0.06) 0%, transparent 55%);
  background-attachment: fixed;
  overflow-x: hidden;
  transition: background-color var(--panda-transition), color var(--panda-transition);
}

body.dark-mode {
  --panda-bg: #0d0e1a;
  --panda-bg-alt: #141527;
  --panda-surface: rgba(26, 27, 46, 0.7);
  --panda-surface-solid: #1a1b2e;
  --panda-border: rgba(255, 255, 255, 0.1);
  --panda-text: #eef0f7;
  --panda-text-soft: #c3c7d9;
  --panda-text-muted: #9aa0b8;
  --panda-primary: #ff5c78;
  --panda-primary-dark: #e94560;
  --panda-primary-soft: rgba(255, 92, 120, 0.14);
  --panda-accent: #5b8def;
  --panda-accent-soft: rgba(91, 141, 239, 0.12);
  --panda-deep: #0a0b16;
  --panda-shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --panda-shadow-md: 0 8px 24px rgba(0, 0, 0, 0.4);
  --panda-shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.55);
  --panda-gradient-hero: linear-gradient(135deg, #0a0b16 0%, #141527 40%, #1d2140 72%, #e94560 140%);
  --panda-gradient-soft: linear-gradient(135deg, rgba(255, 92, 120, 0.14) 0%, rgba(91, 141, 239, 0.14) 100%);
  background-image:
    radial-gradient(circle at 12% 8%, rgba(255, 92, 120, 0.1) 0%, transparent 42%),
    radial-gradient(circle at 88% 4%, rgba(91, 141, 239, 0.12) 0%, transparent 46%),
    radial-gradient(circle at 50% 100%, rgba(233, 69, 96, 0.06) 0%, transparent 55%);
}

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

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

a:hover,
a:focus-visible {
  color: var(--panda-primary-dark);
  text-decoration: underline;
  text-underline-offset: 3px;
}

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

h1, h2, h3, h4, h5, h6 {
  margin: 0 0 0.6em;
  line-height: 1.3;
  font-weight: 700;
  color: var(--panda-text);
  letter-spacing: -0.01em;
}

h1 {
  font-size: clamp(1.7rem, 3.6vw, 2.6rem);
  background: var(--panda-gradient-primary);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

h2 {
  font-size: clamp(1.4rem, 2.6vw, 1.95rem);
  position: relative;
  padding-left: 18px;
}

h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.18em;
  bottom: 0.18em;
  width: 6px;
  border-radius: var(--panda-radius-pill);
  background: var(--panda-gradient-primary);
}

h3 {
  font-size: clamp(1.12rem, 1.8vw, 1.3rem);
  color: var(--panda-text);
}

h4 {
  font-size: 1.05rem;
}

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

ul, ol {
  margin: 0 0 1em;
  padding-left: 1.4em;
  color: var(--panda-text-soft);
}

li {
  margin-bottom: 0.4em;
}

strong {
  color: var(--panda-text);
}

/* ===== Header ===== */
header[role="banner"] {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--panda-surface);
  -webkit-backdrop-filter: var(--panda-glass-blur);
  backdrop-filter: var(--panda-glass-blur);
  border-bottom: 1px solid var(--panda-border);
  box-shadow: var(--panda-shadow-sm);
  transition: background var(--panda-transition), box-shadow var(--panda-transition);
}

.brand-bar {
  max-width: 1240px;
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  gap: 18px;
  flex-wrap: wrap;
}

.brand-logo {
  flex-shrink: 0;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: var(--panda-gradient-hero);
  box-shadow: 0 4px 16px rgba(233, 69, 96, 0.35);
  transition: transform var(--panda-transition), box-shadow var(--panda-transition);
}

.brand-logo:hover {
  transform: rotate(-8deg) scale(1.06);
  box-shadow: 0 6px 22px rgba(233, 69, 96, 0.5);
}

.brand-logo svg {
  width: 44px;
  height: 44px;
}

.brand-text {
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.brand-name {
  margin: 0;
  font-size: 1.3rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  background: var(--panda-gradient-primary);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.brand-slogan {
  margin: 0;
  font-size: 0.8rem;
  color: var(--panda-text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.brand-actions {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.brand-actions form {
  display: flex;
  align-items: center;
  gap: 6px;
  background: var(--panda-bg-alt);
  border: 1px solid var(--panda-border);
  border-radius: var(--panda-radius-pill);
  padding: 4px 4px 4px 14px;
  transition: box-shadow var(--panda-transition), border-color var(--panda-transition);
}

.brand-actions form:focus-within {
  border-color: var(--panda-primary);
  box-shadow: 0 0 0 3px var(--panda-primary-soft);
}

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

.brand-actions input[type="search"] {
  border: none;
  background: transparent;
  font-family: inherit;
  font-size: 0.9rem;
  color: var(--panda-text);
  width: 200px;
  padding: 6px 0;
  outline: none;
}

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

.brand-actions button {
  font-family: inherit;
  font-size: 0.85rem;
  font-weight: 600;
  border: none;
  border-radius: var(--panda-radius-pill);
  padding: 8px 16px;
  cursor: pointer;
  background: var(--panda-gradient-primary);
  color: #fff;
  transition: transform var(--panda-transition), box-shadow var(--panda-transition), opacity var(--panda-transition);
}

.brand-actions button:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 14px rgba(233, 69, 96, 0.4);
}

.brand-actions button:active {
  transform: translateY(0);
}

#theme-toggle,
#menu-toggle {
  background: var(--panda-bg-alt);
  color: var(--panda-text);
  border: 1px solid var(--panda-border);
  padding: 8px 16px;
}

#theme-toggle:hover,
#menu-toggle:hover {
  background: var(--panda-primary-soft);
  color: var(--panda-primary);
  border-color: var(--panda-primary);
  box-shadow: none;
}

#menu-toggle {
  display: none;
}

/* ===== Navigation ===== */
header nav[aria-label="主导航"] {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px 12px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
}

header nav[aria-label="主导航"]::-webkit-scrollbar {
  height: 4px;
}

header nav[aria-label="主导航"]::-webkit-scrollbar-thumb {
  background: var(--panda-border);
  border-radius: var(--panda-radius-pill);
}

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

header nav li {
  margin: 0;
  flex-shrink: 0;
}

header nav a {
  display: inline-block;
  padding: 7px 14px;
  font-size: 0.86rem;
  font-weight: 500;
  color: var(--panda-text-soft);
  border-radius: var(--panda-radius-pill);
  white-space: nowrap;
  transition: background var(--panda-transition), color var(--panda-transition), transform var(--panda-transition);
}

header nav a:hover,
header nav a:focus-visible {
  background: var(--panda-primary-soft);
  color: var(--panda-primary);
  text-decoration: none;
  transform: translateY(-1px);
}

/* ===== Main layout ===== */
main {
  max-width: 1240px;
  margin: 0 auto;
  padding: 32px 24px 64px;
  display: flex;
  flex-direction: column;
  gap: 32px;
}

main > section {
  background: var(--panda-surface);
  -webkit-backdrop-filter: var(--panda-glass-blur);
  backdrop-filter: var(--panda-glass-blur);
  border: 1px solid var(--panda-border);
  border-radius: var(--panda-radius-lg);
  padding: clamp(20px, 3.4vw, 40px);
  box-shadow: var(--panda-shadow-sm);
  position: relative;
  overflow: hidden;
  transition: box-shadow var(--panda-transition), transform var(--panda-transition), border-color var(--panda-transition);
  animation: panda-fade-up 0.6s cubic-bezier(0.22, 0.61, 0.36, 1) both;
}

main > section::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.18) 0%, transparent 45%);
  opacity: 0.6;
}

body.dark-mode main > section::after {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.04) 0%, transparent 45%);
}

main > section:hover {
  box-shadow: var(--panda-shadow-md);
  border-color: rgba(233, 69, 96, 0.24);
}

main > section > * {
  position: relative;
  z-index: 1;
}

/* Hero / intro section */
#intro {
  background: var(--panda-gradient-hero);
  border: 1px solid rgba(255, 255, 255, 0.12);
  box-shadow: var(--panda-shadow-lg);
  padding: clamp(28px, 4vw, 56px);
  color: #fff;
}

#intro::before {
  content: "";
  position: absolute;
  top: -120px;
  right: -120px;
  width: 340px;
  height: 340px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(233, 69, 96, 0.45) 0%, transparent 68%);
  filter: blur(10px);
  pointer-events: none;
}

#intro::after {
  content: "";
  position: absolute;
  bottom: -140px;
  left: -100px;
  width: 300px;
  height: 300px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(91, 141, 239, 0.35) 0%, transparent 68%);
  filter: blur(10px);
  pointer-events: none;
}

#intro h1 {
  -webkit-text-fill-color: #ffffff;
  color: #ffffff;
  background: none;
  font-size: clamp(1.7rem, 3.8vw, 2.7rem);
  text-shadow: 0 2px 18px rgba(0, 0, 0, 0.35);
  margin-bottom: 0.5em;
}

#intro p {
  color: rgba(255, 255, 255, 0.86);
  max-width: 78ch;
  font-size: 1.02rem;
}

#intro p:last-of-type {
  margin-bottom: 0;
}

#intro figure {
  margin: 28px 0 0;
  border-radius: var(--panda-radius-md);
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.16);
  box-shadow: var(--panda-shadow-lg);
  background: rgba(0, 0, 0, 0.2);
  transition: transform var(--panda-transition), box-shadow var(--panda-transition);
}

#intro figure:hover {
  transform: translateY(-4px) scale(1.005);
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.5);
}

#intro figure svg {
  width: 100%;
  display: block;
}

#intro figcaption {
  padding: 12px 18px;
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.7);
  background: rgba(0, 0, 0, 0.28);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  text-align: center;
}

/* ===== Article cards ===== */
#articles {
  display: block;
}

#articles > article {
  background: var(--panda-bg-alt);
  border: 1px solid var(--panda-border);
  border-radius: var(--panda-radius-md);
  padding: 20px 22px;
  margin-bottom: 16px;
  box-shadow: var(--panda-shadow-sm);
  position: relative;
  overflow: hidden;
  transition: transform var(--panda-transition), box-shadow var(--panda-transition), border-color var(--panda-transition);
}

#articles > article::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 4px;
  background: var(--panda-gradient-primary);
  transform: scaleY(0);
  transform-origin: top;
  transition: transform var(--panda-transition);
}

#articles > article:hover {
  transform: translateY(-4px);
  box-shadow: var(--panda-shadow-md);
  border-color: rgba(233, 69, 96, 0.3);
}

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

#articles > article h3 {
  margin-top: 0;
  margin-bottom: 8px;
  transition: color var(--panda-transition);
}

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

#articles > article p {
  font-size: 0.92rem;
  margin-bottom: 8px;
}

#articles > article p:first-of-type {
  font-size: 0.8rem;
  color: var(--panda-text-muted);
  font-weight: 500;
  letter-spacing: 0.01em;
}

#articles > article a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-weight: 600;
  font-size: 0.88rem;
  padding: 6px 14px;
  border-radius: var(--panda-radius-pill);
  background: var(--panda-primary-soft);
  transition: background var(--panda-transition), color var(--panda-transition), transform var(--panda-transition);
}

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

#articles > article a:hover {
  background: var(--panda-gradient-primary);
  color: #fff;
  text-decoration: none;
  transform: translateX(2px);
}

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

/* Full article sections */
#articles > section {
  background: var(--panda-gradient-soft);
  border: 1px solid var(--panda-border);
  border-radius: var(--panda-radius-md);
  padding: 20px 22px;
  margin-bottom: 16px;
  transition: box-shadow var(--panda-transition), border-color var(--panda-transition);
}

#articles > section:hover {
  box-shadow: var(--panda-shadow-sm);
  border-color: rgba(233, 69, 96, 0.25);
}

#articles > section h4 {
  margin-top: 0;
  color: var(--panda-accent);
  font-size: 1rem;
}

#articles > section p {
  font-size: 0.94rem;
  margin-bottom: 0;
}

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

#faq details:hover {
  border-color: rgba(233, 69, 96, 0.3);
  box-shadow: var(--panda-shadow-sm);
}

#faq details[open] {
  border-color: rgba(233, 69, 96, 0.4);
  box-shadow: var(--panda-shadow-md);
  background: var(--panda-surface-solid);
}

#faq summary {
  cursor: pointer;
  padding: 16px 48px 16px 20px;
  font-weight: 600;
  font-size: 0.98rem;
  color: var(--panda-text);
  list-style: none;
  position: relative;
  user-select: none;
  transition: color var(--panda-transition), background var(--panda-transition);
}

#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;
  border-radius: 50%;
  background: var(--panda-primary-soft);
  color: var(--panda-primary);
  transition: transform var(--panda-transition), background var(--panda-transition), color var(--panda-transition);
}

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

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

#faq details p {
  padding: 0 20px 18px;
  margin: 0;
  font-size: 0.93rem;
  animation: panda-fade-in 0.35s ease both;
}

/* ===== Blockquotes (reviews) ===== */
#reviews blockquote {
  margin: 0 0 16px;
  padding: 18px 22px 18px 26px;
  background: var(--panda-bg-alt);
  border: 1px solid var(--panda-border);
  border-left: 4px solid var(--panda-primary);
  border-radius: var(--panda-radius-md);
  position: relative;
  transition: transform var(--panda-transition), box-shadow var(--panda-transition);
}

#reviews blockquote::before {
  content: "“";
  position: absolute;
  top: 2px;
  left: 10px;
  font-size: 2.6rem;
  line-height: 1;
  color: var(--panda-primary);
  opacity: 0.25;
  font-family: Georgia, serif;
}

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

#reviews blockquote p {
  margin: 0;
  font-size: 0.95rem;
  font-style: italic;
  color: var(--panda-text-soft);
}

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

#howto ol li {
  counter-increment: panda-step;
  position: relative;
  padding: 10px 0 10px 48px;
  border-bottom: 1px dashed var(--panda-border);
  font-size: 0.95rem;
}

#howto ol li:last-child {
  border-bottom: none;
}

#howto ol li::before {
  content: counter(panda-step);
  position: absolute;
  left: 0;
  top: 8px;
  width: 30px;
  height: 30px;
  display: grid;
  place-items: center;
  font-size: 0.85rem;
  font-weight: 700;
  color: #fff;
  border-radius: 50%;
  background: var(--panda-gradient-primary);
  box-shadow: 0 3px 10px rgba(233, 69, 96, 0.35);
}

/* ===== Contact list ===== */
#contact ul {
  list-style: none;
  padding-left: 0;
  display: grid;
  gap: 10px;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

#contact ul li {
  background: var(--panda-bg-alt);
  border: 1px solid var(--panda-border);
  border-radius: var(--panda-radius-sm);
  padding: 12px 16px;
  font-size: 0.92rem;
  margin: 0;
  transition: transform var(--panda-transition), border-color var(--panda-transition), box-shadow var(--panda-transition);
}

#contact ul li:hover {
  transform: translateY(-2px);
  border-color: rgba(233, 69, 96, 0.35);
  box-shadow: var(--panda-shadow-sm);
}

/* ===== 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: 8px 16px;
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--panda-text-soft);
  background: var(--panda-bg-alt);
  border: 1px solid var(--panda-border);
  border-radius: var(--panda-radius-pill);
  transition: background var(--panda-transition), color var(--panda-transition), border-color var(--panda-transition), transform var(--panda-transition), box-shadow var(--panda-transition);
}

#sitemap a:hover,
#links a:hover {
  background: var(--panda-gradient-primary);
  color: #fff;
  border-color: transparent;
  text-decoration: none;
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(233, 69, 96, 0.35);
}

/* ===== Footer ===== */
footer[role="contentinfo"] {
  background: var(--panda-gradient-hero);
  color: rgba(255, 255, 255, 0.82);
  padding: clamp(32px, 4vw, 56px) 24px 32px;
  position: relative;
  overflow: hidden;
}

footer[role="contentinfo"]::before {
  content: "";
  position: absolute;
  top: -160px;
  right: -100px;
  width: 360px;
  height: 360px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(233, 69, 96, 0.3) 0%, transparent 68%);
  pointer-events: none;
}

footer[role="contentinfo"] > section {
  max-width: 1240px;
  margin: 0 auto 28px;
  position: relative;
  z-index: 1;
}

footer[role="contentinfo"] h2 {
  color: #fff;
  font-size: 1.1rem;
  padding-left: 0;
  margin-bottom: 0.6em;
}

footer[role="contentinfo"] h2::before {
  display: none;
}

footer[role="contentinfo"] p {
  color: rgba(255, 255, 255, 0.72);
  font-size: 0.9rem;
  max-width: 80ch;
  margin-bottom: 0.6em;
}

footer[role="contentinfo"] p:last-child {
  margin-bottom: 0;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.14);
  font-size: 0.84rem;
  color: rgba(255, 255, 255, 0.6);
  text-align: center;
}

/* ===== Animations ===== */
@keyframes panda-fade-up {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

@keyframes panda-pulse {
  0%, 100% {
    box-shadow: 0 0 0 0 rgba(233, 69, 96, 0.4);
  }
  50% {
    box-shadow: 0 0 0 10px rgba(233, 69, 96, 0);
  }
}

main > section:nth-child(2) { animation-delay: 0.05s; }
main > section:nth-child(3) { animation-delay: 0.1s; }
main > section:nth-child(4) { animation-delay: 0.15s; }
main > section:nth-child(5) { animation-delay: 0.2s; }
main > section:nth-child(6) { animation-delay: 0.25s; }
main > section:nth-child(7) { animation-delay: 0.3s; }
main > section:nth-child(8) { animation-delay: 0.35s; }
main > section:nth-child(9) { animation-delay: 0.4s; }
main > section:nth-child(10) { animation-delay: 0.45s; }
main > section:nth-child(11) { animation-delay: 0.5s; }
main > section:nth-child(12) { animation-delay: 0.55s; }
main > section:nth-child(13) { animation-delay: 0.6s; }
main > section:nth-child(14) { animation-delay: 0.65s; }
main > section:nth-child(15) { animation-delay: 0.7s; }
main > section:nth-child(16) { animation-delay: 0.75s; }
main > section:nth-child(17) { animation-delay: 0.8s; }
main > section:nth-child(18) { animation-delay: 0.85s; }

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .brand-bar {
    padding: 12px 18px;
  }

  .brand-actions input[type="search"] {
    width: 160px;
  }

  main {
    padding: 24px 18px 48px;
    gap: 24px;
  }

  header nav[aria-label="主导航"] {
    padding: 0 18px 10px;
  }
}

@media (max-width: 768px) {
  html {
    scroll-padding-top: 140px;
  }

  .brand-bar {
    gap: 12px;
  }

  .brand-logo {
    width: 44px;
    height: 44px;
  }

  .brand-logo svg {
    width: 38px;
    height: 38px;
  }

  .brand-name {
    font-size: 1.12rem;
  }

  .brand-slogan {
    font-size: 0.72rem;
    white-space: normal;
  }

  .brand-actions {
    width: 100%;
    margin-left: 0;
    order: 3;
  }

  .brand-actions form {
    flex: 1 1 auto;
    min-width: 0;
  }

  .brand-actions input[type="search"] {
    width: 100%;
    min-width: 0;
  }

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

  header nav[aria-label="主导航"] {
    display: none;
    padding: 0 18px 14px;
  }

  header nav[aria-label="主导航"].is-open {
    display: block;
    animation: panda-fade-in 0.3s ease both;
  }

  header nav ul {
    flex-wrap: wrap;
    gap: 8px;
  }

  header nav a {
    font-size: 0.82rem;
    padding: 6px 12px;
  }

  main > section {
    border-radius: var(--panda-radius-md);
  }

  #intro {
    padding: 24px 20px;
  }

  #intro figure {
    margin-top: 20px;
  }

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

  #faq summary {
    padding: 14px 44px 14px 16px;
    font-size: 0.92rem;
  }

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

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

  footer[role="contentinfo"] {
    padding: 32px 18px 24px;
  }
}

@media (max-width: 480px) {
  body {
    font-size: 15px;
  }

  .brand-actions button {
    padding: 8px 12px;
    font-size: 0.8rem;
  }

  #theme-toggle,
  #menu-toggle {
    padding: 8px 12px;
  }

  main {
    padding: 18px 14px 40px;
  }

  main > section {
    padding: 18px 16px;
  }

  h2 {
    padding-left: 14px;
  }

  h2::before {
    width: 4px;
  }

  #sitemap a,
  #links a {
    padding: 7px 12px;
    font-size: 0.82rem;
  }

  #howto ol li {
    padding-left: 42px;
  }
}

/* ===== Accessibility / motion ===== */
@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;
  }
}

/* ===== Print ===== */
@media print {
  header[role="banner"],
  footer[role="contentinfo"],
  #theme-toggle,
  #menu-toggle,
  .brand-actions form {
    display: none !important;
  }

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

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