:root {
  --brand: #ff6b35;
  --brand-dark: #e8551f;
  --brand-light: #ff8f66;
  --accent: #2b6cb0;
  --accent-2: #38a169;
  --bg: #f7f8fc;
  --bg-elevated: #ffffff;
  --bg-soft: #eef1f8;
  --text: #1a202c;
  --text-soft: #4a5568;
  --text-muted: #718096;
  --border: rgba(26, 32, 44, 0.08);
  --glass: rgba(255, 255, 255, 0.62);
  --glass-border: rgba(255, 255, 255, 0.45);
  --shadow-sm: 0 2px 8px rgba(26, 32, 44, 0.06);
  --shadow-md: 0 8px 28px rgba(26, 32, 44, 0.1);
  --shadow-lg: 0 18px 48px rgba(26, 32, 44, 0.14);
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --grad-banner: linear-gradient(135deg, #ff6b35 0%, #ff9a5a 45%, #ffb347 100%);
  --grad-brand: linear-gradient(135deg, #ff6b35 0%, #ff8f66 100%);
  --grad-accent: linear-gradient(135deg, #2b6cb0 0%, #4299e1 100%);
  --grad-soft: linear-gradient(135deg, rgba(255, 107, 53, 0.08), rgba(43, 108, 176, 0.06));
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
  --transition: 0.35s var(--ease);
  --maxw: 1200px;
}

[data-theme="dark"] {
  --bg: #0e1117;
  --bg-elevated: #171c26;
  --bg-soft: #1d2430;
  --text: #e8edf5;
  --text-soft: #b6c0d0;
  --text-muted: #8592a6;
  --border: rgba(255, 255, 255, 0.08);
  --glass: rgba(23, 28, 38, 0.6);
  --glass-border: rgba(255, 255, 255, 0.1);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 8px 28px rgba(0, 0, 0, 0.5);
  --shadow-lg: 0 18px 48px rgba(0, 0, 0, 0.6);
  --grad-soft: linear-gradient(135deg, rgba(255, 107, 53, 0.14), rgba(43, 108, 176, 0.1));
}

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

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

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.75;
  color: var(--text);
  background: var(--bg);
  background-image: radial-gradient(
      circle at 12% 8%,
      rgba(255, 107, 53, 0.07),
      transparent 42%
    ),
    radial-gradient(circle at 88% 22%, rgba(43, 108, 176, 0.07), transparent 40%);
  background-attachment: fixed;
  transition: background-color var(--transition), color var(--transition);
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  margin: 0 0 0.6em;
  line-height: 1.32;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--text);
}

h1 { font-size: clamp(1.6rem, 4.2vw, 2.6rem); }
h2 { font-size: clamp(1.35rem, 3vw, 2rem); }
h3 { font-size: clamp(1.1rem, 2.2vw, 1.35rem); }

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

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

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

a:focus-visible,
button:focus-visible,
input:focus-visible {
  outline: 3px solid rgba(255, 107, 53, 0.55);
  outline-offset: 2px;
  border-radius: 6px;
}

ul, ol {
  padding-left: 1.4em;
  margin: 0 0 1em;
}

li {
  margin-bottom: 0.4em;
  color: var(--text-soft);
}

img, svg {
  max-width: 100%;
  vertical-align: middle;
}

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

.header-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0.7rem 1.25rem;
  display: flex;
  align-items: center;
  gap: 1.25rem;
  flex-wrap: wrap;
}

.brand a {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: var(--text);
  font-weight: 800;
}

.brand svg {
  border-radius: 12px;
  box-shadow: 0 6px 18px rgba(255, 107, 53, 0.35);
  transition: transform var(--transition);
}

.brand a:hover svg {
  transform: rotate(-6deg) scale(1.06);
}

.brand-name {
  font-size: 1.2rem;
  background: var(--grad-brand);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  letter-spacing: 0.02em;
}

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

.main-nav {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.15rem;
}

.main-nav li {
  margin: 0;
}

.main-nav a {
  display: block;
  padding: 0.42rem 0.72rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-soft);
  border-radius: 999px;
  white-space: nowrap;
  transition: background var(--transition), color var(--transition),
    transform var(--transition);
}

.main-nav a:hover {
  color: var(--brand);
  background: rgba(255, 107, 53, 0.1);
  transform: translateY(-2px);
}

.header-tools {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-left: auto;
}

.header-tools form {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.header-tools input[type="search"] {
  width: 170px;
  padding: 0.45rem 0.85rem;
  font-size: 0.88rem;
  color: var(--text);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 999px;
  transition: border-color var(--transition), box-shadow var(--transition),
    width var(--transition);
}

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

.header-tools input[type="search"]:focus {
  border-color: var(--brand);
  box-shadow: 0 0 0 4px rgba(255, 107, 53, 0.16);
  width: 200px;
  outline: none;
}

.header-tools button {
  padding: 0.45rem 0.95rem;
  font-size: 0.88rem;
  font-weight: 700;
  color: #fff;
  background: var(--grad-brand);
  border: none;
  border-radius: 999px;
  cursor: pointer;
  transition: transform var(--transition), box-shadow var(--transition),
    filter var(--transition);
}

.header-tools button:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(255, 107, 53, 0.35);
  filter: brightness(1.05);
}

#theme-toggle {
  background: var(--bg-elevated);
  color: var(--text-soft);
  border: 1px solid var(--border);
}

#theme-toggle:hover {
  color: var(--brand);
  box-shadow: var(--shadow-sm);
}

#mobile-menu-toggle {
  display: none;
  background: var(--bg-elevated);
  color: var(--text-soft);
  border: 1px solid var(--border);
}

/* ============ 主内容容器 ============ */
main {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 1.5rem 1.25rem 3rem;
}

main > section,
main > nav {
  margin-bottom: 2rem;
}

section {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: clamp(1.25rem, 3vw, 2.5rem);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition),
    border-color var(--transition);
}

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

section h2 {
  position: relative;
  padding-left: 0.9rem;
}

section h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.18em;
  bottom: 0.18em;
  width: 5px;
  border-radius: 999px;
  background: var(--grad-brand);
}

section h3 {
  margin-top: 1.4em;
  color: var(--text);
}

/* ============ Hero ============ */
#hero {
  padding: 0;
  overflow: hidden;
  background: var(--grad-soft), var(--bg-elevated);
  border-radius: var(--radius-xl);
  position: relative;
}

#hero::before {
  content: "";
  position: absolute;
  inset: -40% -20% auto -20%;
  height: 320px;
  background: radial-gradient(
    circle at 30% 40%,
    rgba(255, 107, 53, 0.18),
    transparent 60%
  );
  pointer-events: none;
}

.hero-inner {
  position: relative;
  padding: clamp(1.5rem, 4vw, 3rem);
}

#hero-title {
  background: linear-gradient(120deg, var(--brand) 0%, #ff9a5a 55%, var(--accent) 130%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 0.75rem;
}

.hero-lead {
  font-size: clamp(0.95rem, 1.6vw, 1.08rem);
  color: var(--text-soft);
  max-width: 900px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  margin: 1.5rem 0 2rem;
}

.btn-primary,
.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.8rem 1.6rem;
  font-size: 0.98rem;
  font-weight: 700;
  border-radius: 999px;
  transition: transform var(--transition), box-shadow var(--transition),
    background var(--transition), color var(--transition);
}

.btn-primary {
  color: #fff;
  background: var(--grad-brand);
  box-shadow: 0 10px 26px rgba(255, 107, 53, 0.35);
}

.btn-primary:hover {
  color: #fff;
  transform: translateY(-3px);
  box-shadow: 0 16px 34px rgba(255, 107, 53, 0.45);
}

.btn-secondary {
  color: var(--text);
  background: var(--bg-elevated);
  border: 1.5px solid var(--border);
}

.btn-secondary:hover {
  color: var(--brand);
  border-color: var(--brand);
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.85rem;
  margin-bottom: 1.75rem;
}

.stat {
  padding: 1rem 0.75rem;
  text-align: center;
  background: var(--glass);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition);
}

.stat:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.stat-num {
  display: block;
  font-size: clamp(1.3rem, 2.6vw, 1.9rem);
  font-weight: 800;
  line-height: 1.2;
  background: var(--grad-brand);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.stat-label {
  display: block;
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 0.2rem;
}

.hero-banner {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

.hero-banner .slide {
  display: none;
  animation: slideFade 0.7s var(--ease);
}

.hero-banner .slide.active {
  display: block;
}

.hero-banner .slide svg {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--radius-lg);
  transition: transform 0.6s var(--ease);
}

.hero-banner:hover .slide.active svg {
  transform: scale(1.03);
}

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

/* ============ 面包屑 ============ */
.breadcrumb {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.35rem;
  margin: 0;
  padding: 0.55rem 1rem;
  font-size: 0.85rem;
  background: var(--glass);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border);
  border-radius: 999px;
}

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

.breadcrumb li + li::before {
  content: "/";
  margin-right: 0.35rem;
  color: var(--text-muted);
  opacity: 0.6;
}

/* ============ 案例引用 ============ */
blockquote {
  margin: 1rem 0;
  padding: 1rem 1.25rem;
  background: var(--grad-soft);
  border-left: 4px solid var(--brand);
  border-radius: var(--radius-sm);
  transition: transform var(--transition), box-shadow var(--transition);
}

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

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

/* ============ 新闻 / 文章卡片 ============ */
#news article,
#articles article {
  padding: 1.15rem 1.35rem;
  margin-bottom: 1rem;
  background: var(--bg-soft);
  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);
}

#news article:hover,
#articles article:hover {
  transform: translateY(-4px);
  border-color: rgba(255, 107, 53, 0.35);
  box-shadow: var(--shadow-md);
  background: var(--bg-elevated);
}

#news article h3,
#articles article h3 {
  margin-top: 0;
  margin-bottom: 0.35rem;
}

#news article h3 a,
#articles article h3 a {
  color: var(--text);
}

#news article h3 a:hover,
#articles article h3 a:hover {
  color: var(--brand);
}

#news time,
#articles time {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--brand);
  background: rgba(255, 107, 53, 0.1);
  padding: 0.1rem 0.6rem;
  border-radius: 999px;
  margin-bottom: 0.5rem;
}

#articles article > a:last-child {
  display: inline-flex;
  align-items: center;
  font-size: 0.88rem;
  font-weight: 700;
  margin-top: 0.35rem;
}

#articles article > a:last-child::after {
  content: "→";
  margin-left: 0.3rem;
  transition: transform var(--transition);
}

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

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

#howto ol li {
  position: relative;
  padding: 0.85rem 1rem 0.85rem 3.2rem;
  margin-bottom: 0.65rem;
  background: var(--bg-soft);
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  transition: transform var(--transition), box-shadow var(--transition);
}

#howto ol li::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 0.9rem;
  top: 50%;
  transform: translateY(-50%);
  width: 1.7rem;
  height: 1.7rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.85rem;
  font-weight: 800;
  color: #fff;
  background: var(--grad-brand);
  border-radius: 50%;
  box-shadow: 0 4px 12px rgba(255, 107, 53, 0.35);
}

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

/* ============ FAQ ============ */
.faq-item {
  margin-bottom: 0.75rem;
  padding: 1rem 1.25rem;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  transition: transform var(--transition), box-shadow var(--transition),
    border-color var(--transition);
}

.faq-item:hover {
  transform: translateY(-3px);
  border-color: rgba(255, 107, 53, 0.35);
  box-shadow: var(--shadow-md);
}

.faq-item h3 {
  margin: 0 0 0.5rem;
  font-size: 1.02rem;
  color: var(--text);
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
}

.faq-item h3::before {
  content: "Q";
  flex: 0 0 auto;
  width: 1.4rem;
  height: 1.4rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0.78rem;
  font-weight: 800;
  color: #fff;
  background: var(--grad-accent);
  border-radius: 8px;
  margin-top: 0.15rem;
}

.faq-item p {
  margin: 0;
  padding-left: 1.9rem;
  font-size: 0.95rem;
}

/* ============ 联系 / 地图 / 友链 ============ */
.contact-list,
.sitemap-list,
.friend-links {
  list-style: none;
  padding: 0;
  display: grid;
  gap: 0.5rem;
}

.contact-list {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.contact-list li {
  padding: 0.7rem 1rem;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 0.92rem;
  transition: transform var(--transition), box-shadow var(--transition);
}

.contact-list li:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-sm);
}

.sitemap-list,
.friend-links {
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
}

.sitemap-list a,
.friend-links a {
  display: block;
  padding: 0.6rem 0.9rem;
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-soft);
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
}

.sitemap-list a:hover,
.friend-links a:hover {
  color: #fff;
  background: var(--grad-brand);
  border-color: transparent;
  transform: translateY(-3px);
  box-shadow: 0 8px 20px rgba(255, 107, 53, 0.3);
}

#notice {
  background: linear-gradient(135deg, rgba(255, 107, 53, 0.09), rgba(43, 108, 176, 0.06)),
    var(--bg-elevated);
  border-color: rgba(255, 107, 53, 0.25);
}

/* ============ 页脚 ============ */
#site-footer {
  background: linear-gradient(180deg, var(--bg-soft), var(--bg-elevated));
  border-top: 1px solid var(--border);
  margin-top: 2rem;
}

.footer-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 2.5rem 1.25rem 1.5rem;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.5rem;
}

.footer-inner section {
  background: transparent;
  border: none;
  box-shadow: none;
  padding: 0;
  border-radius: 0;
}

.footer-inner section:hover {
  box-shadow: none;
}

.footer-inner h2 {
  font-size: 1rem;
  padding-left: 0;
  margin-bottom: 0.6rem;
  color: var(--text);
}

.footer-inner h2::before {
  display: none;
}

.footer-inner p {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin: 0;
}

.footer-inner .copyright {
  grid-column: 1 / -1;
  text-align: center;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border);
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* ============ 返回顶部 ============ */
#back-to-top {
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  z-index: 90;
  padding: 0.7rem 1.05rem;
  font-size: 0.85rem;
  font-weight: 700;
  color: #fff;
  background: var(--grad-brand);
  border: none;
  border-radius: 999px;
  cursor: pointer;
  box-shadow: 0 10px 26px rgba(255, 107, 53, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px);
  transition: opacity var(--transition), transform var(--transition),
    visibility var(--transition), box-shadow var(--transition);
}

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

#back-to-top:hover {
  transform: translateY(-3px);
  box-shadow: 0 16px 34px rgba(255, 107, 53, 0.5);
}

/* ============ 滚动进场动画 ============ */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
  will-change: opacity, transform;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
  .reveal {
    opacity: 1;
    transform: none;
  }
}

/* ============ 响应式 ============ */
@media (max-width: 1024px) {
  .header-tools input[type="search"] {
    width: 140px;
  }
  .header-tools input[type="search"]:focus {
    width: 160px;
  }
  .main-nav a {
    padding: 0.38rem 0.55rem;
    font-size: 0.85rem;
  }
}

@media (max-width: 900px) {
  .hero-stats {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .header-inner {
    gap: 0.75rem;
  }
  nav[aria-label="主导航"] {
    order: 4;
    flex-basis: 100%;
  }
  .main-nav {
    justify-content: center;
    padding-top: 0.3rem;
    border-top: 1px solid var(--border);
    margin-top: 0.3rem;
  }
}

@media (max-width: 640px) {
  body {
    font-size: 15px;
  }
  main {
    padding: 1rem 0.85rem 2rem;
  }
  section {
    padding: 1.15rem;
    border-radius: var(--radius-md);
  }
  #hero {
    border-radius: var(--radius-lg);
  }
  .hero-inner {
    padding: 1.25rem;
  }
  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }
  .btn-primary,
  .btn-secondary {
    width: 100%;
  }
  .hero-stats {
    gap: 0.6rem;
  }
  .stat {
    padding: 0.8rem 0.5rem;
  }
  #mobile-menu-toggle {
    display: inline-block;
  }
  nav[aria-label="主导航"] {
    display: none;
  }
  #site-header.menu-open nav[aria-label="主导航"] {
    display: block;
  }
  #site-header.menu-open .main-nav {
    flex-direction: column;
    align-items: stretch;
  }
  #site-header.menu-open .main-nav a {
    padding: 0.6rem 0.9rem;
    text-align: center;
  }
  .header-tools {
    flex: 1 1 100%;
    margin-left: 0;
  }
  .header-tools form {
    flex: 1 1 auto;
  }
  .header-tools input[type="search"] {
    flex: 1 1 auto;
    width: 100%;
    min-width: 0;
  }
  .header-tools input[type="search"]:focus {
    width: 100%;
  }
  .faq-item {
    padding: 0.9rem;
  }
  .faq-item p {
    padding-left: 0;
  }
  .footer-inner {
    padding: 1.75rem 1rem 1.25rem;
    gap: 1.15rem;
  }
  #back-to-top {
    right: 0.85rem;
    bottom: 0.85rem;
    padding: 0.6rem 0.9rem;
  }
}

@media (max-width: 400px) {
  .hero-stats {
    grid-template-columns: 1fr;
  }
  .brand-name {
    font-size: 1.05rem;
  }
}