/* =========================================================
   漫蛙漫画 style.css
   风格：奇幻异世界 · 深蓝紫渐变 · 玻璃拟态 · 圆角卡片
   响应式 + 暗色模式 + 滚动动画 + Hover动画
   ========================================================= */

/* ===== 主题变量 (浅色) ===== */
:root {
  --bg: #f6f7fb;
  --bg-soft: #eef0f6;
  --card-bg: rgba(255, 255, 255, 0.72);
  --card-border: rgba(255, 255, 255, 0.5);
  --text-primary: #1e2433;
  --text-secondary: #3d4a5c;
  --text-muted: #5b6b7f;
  --heading-color: #141a26;
  --border-color: rgba(30, 41, 59, 0.08);
  --footer-bg: #0d1526;
  --footer-text: #cbd5e1;
  --link-color: #4f46e5;
  --btn-bg: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
  --btn-text: #ffffff;
  --shadow: 0 10px 30px rgba(79, 70, 229, 0.08), 0 2px 8px rgba(0, 0, 0, 0.04);
  --shadow-hover: 0 20px 40px rgba(79, 70, 229, 0.15), 0 4px 12px rgba(0, 0, 0, 0.06);
  --hero-grad-start: #1e1b4b;
  --hero-grad-mid: #312e81;
  --hero-grad-end: #4c1d95;
  --hero-overlay: rgba(15, 23, 42, 0.65);
  --glass-bg: rgba(255, 255, 255, 0.08);
  --glass-border: rgba(255, 255, 255, 0.15);
  --accent-glow: rgba(124, 58, 237, 0.4);
  --chip-bg: rgba(79, 70, 229, 0.06);
  --chip-border: rgba(79, 70, 229, 0.12);
  --scrollbar-thumb: rgba(79, 70, 229, 0.25);
  --scrollbar-track: transparent;
  --nav-blur: rgba(255, 255, 255, 0.7);
  --footer-link: #a5b4fc;
}

/* ===== 暗色模式变量 ===== */
[data-theme="dark"] {
  --bg: #0b101f;
  --bg-soft: #141c30;
  --card-bg: rgba(23, 31, 52, 0.75);
  --card-border: rgba(148, 163, 184, 0.12);
  --text-primary: #e2e8f0;
  --text-secondary: #b6c2d4;
  --text-muted: #8896a8;
  --heading-color: #f1f5f9;
  --border-color: rgba(148, 163, 184, 0.12);
  --footer-bg: #050a14;
  --footer-text: #a5b4fc;
  --link-color: #93c5fd;
  --btn-bg: linear-gradient(135deg, #6366f1 0%, #a855f7 100%);
  --btn-text: #ffffff;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.3), 0 2px 8px rgba(0, 0, 0, 0.2);
  --shadow-hover: 0 20px 40px rgba(99, 102, 241, 0.25), 0 4px 12px rgba(0, 0, 0, 0.3);
  --hero-grad-start: #0f0c29;
  --hero-grad-mid: #1a1a3e;
  --hero-grad-end: #24243e;
  --hero-overlay: rgba(0, 0, 0, 0.55);
  --glass-bg: rgba(255, 255, 255, 0.04);
  --glass-border: rgba(255, 255, 255, 0.08);
  --accent-glow: rgba(168, 85, 247, 0.35);
  --chip-bg: rgba(99, 102, 241, 0.15);
  --chip-border: rgba(99, 102, 241, 0.25);
  --scrollbar-thumb: rgba(99, 102, 241, 0.35);
  --nav-blur: rgba(11, 16, 31, 0.7);
  --footer-link: #a5b4fc;
}

/* ===== 基础重置 ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-tap-highlight-color: transparent;
}

body {
  font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  background-color: var(--bg);
  background-image: 
    radial-gradient(ellipse 80% 50% at 20% 0%, rgba(99, 102, 241, 0.06) 0%, transparent 60%),
    radial-gradient(ellipse 60% 40% at 90% 10%, rgba(168, 85, 247, 0.05) 0%, transparent 60%);
  color: var(--text-primary);
  line-height: 1.7;
  transition: background 0.3s ease, color 0.3s ease;
  overflow-x: hidden;
  min-height: 100vh;
}

/* ===== 滚动条样式 ===== */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}
::-webkit-scrollbar-track {
  background: var(--scrollbar-track);
}
::-webkit-scrollbar-thumb {
  background: var(--scrollbar-thumb);
  border-radius: 20px;
}

/* ===== 滚动动画 (入场) ===== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

@keyframes pulseGlow {
  0%, 100% { box-shadow: 0 0 20px var(--accent-glow); }
  50% { box-shadow: 0 0 40px var(--accent-glow), 0 0 60px rgba(99, 102, 241, 0.2); }
}

@keyframes shimmer {
  0% { background-position: -1000px 0; }
  100% { background-position: 1000px 0; }
}

/* 标题、卡片等入场动画 */
h1, h2, h3, h4, p, .card, .article-item, .faq-box, .hero-content, .grid, section {
  animation: fadeInUp 0.7s ease both;
}

/* stagger 延迟 */
.grid > *:nth-child(1) { animation-delay: 0.1s; }
.grid > *:nth-child(2) { animation-delay: 0.2s; }
.grid > *:nth-child(3) { animation-delay: 0.3s; }
.article-item:nth-child(1) { animation-delay: 0.05s; }
.article-item:nth-child(2) { animation-delay: 0.1s; }
.article-item:nth-child(3) { animation-delay: 0.15s; }
.article-item:nth-child(4) { animation-delay: 0.2s; }
.article-item:nth-child(5) { animation-delay: 0.25s; }
.article-item:nth-child(6) { animation-delay: 0.3s; }
.article-item:nth-child(7) { animation-delay: 0.35s; }
.article-item:nth-child(8) { animation-delay: 0.4s; }
.article-item:nth-child(9) { animation-delay: 0.45s; }
.article-item:nth-child(10) { animation-delay: 0.5s; }
.faq-box:nth-child(n) { animation-delay: calc(0.05s * var(--i, 1)); }

/* ===== 排版 ===== */
h1, h2, h3, h4 {
  color: var(--heading-color);
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -0.02em;
}

h1 {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 800;
  background: linear-gradient(135deg, #ffffff 0%, #e0e7ff 50%, #c7d2fe 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-fill-color: transparent;
}

h2 {
  font-size: clamp(1.6rem, 3.5vw, 2.2rem);
  margin-top: 3rem;
  margin-bottom: 1rem;
  position: relative;
  padding-bottom: 0.5rem;
  display: inline-block;
}

h2::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 60px;
  height: 4px;
  background: linear-gradient(90deg, #4f46e5, #a855f7);
  border-radius: 4px;
}

h3 {
  font-size: clamp(1.2rem, 2.5vw, 1.5rem);
  margin-top: 2rem;
  margin-bottom: 0.8rem;
}

h4 {
  font-size: clamp(1rem, 2vw, 1.2rem);
  margin-top: 1.2rem;
  color: var(--text-secondary);
}

p {
  color: var(--text-primary);
  margin-bottom: 1.2rem;
  font-size: 1rem;
  line-height: 1.8;
}

a {
  color: var(--link-color);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease, text-decoration 0.2s ease;
}

a:hover {
  text-decoration: underline;
  color: var(--link-color);
}

/* ===== 容器 ===== */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 clamp(1rem, 4vw, 2rem);
}

/* ===== 导航栏 ===== */
.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--nav-blur);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid var(--border-color);
  transition: background 0.3s ease, box-shadow 0.3s ease;
}

.navbar:hover {
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.05);
}

.nav-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
  gap: 1rem;
}

.logo {
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--heading-color);
  letter-spacing: -0.5px;
  background: linear-gradient(135deg, var(--heading-color), var(--link-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  white-space: nowrap;
}

.logo span {
  background: linear-gradient(135deg, #4f46e5, #a855f7);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-links {
  display: flex;
  gap: 2rem;
  align-items: center;
}

.nav-links a {
  color: var(--text-primary);
  font-weight: 500;
  font-size: 0.95rem;
  position: relative;
  transition: color 0.2s ease;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, #4f46e5, #a855f7);
  transition: width 0.3s ease;
  border-radius: 2px;
}

.nav-links a:hover {
  color: var(--link-color);
  text-decoration: none;
}

.nav-links a:hover::after {
  width: 100%;
}

.nav-actions {
  display: flex;
  gap: 0.8rem;
  align-items: center;
}

/* 搜索框 */
.search-box {
  display: flex;
  align-items: center;
  border: 1px solid var(--border-color);
  border-radius: 2.5rem;
  padding: 0.25rem 0.25rem 0.25rem 1rem;
  background: var(--bg-soft);
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
  max-width: 200px;
}

.search-box:focus-within {
  border-color: var(--link-color);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

.search-box input {
  flex: 1;
  border: none;
  background: transparent;
  color: var(--text-primary);
  outline: none;
  padding: 0.3rem 0;
  font-size: 0.9rem;
  min-width: 0;
}

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

.search-box button {
  background: var(--btn-bg);
  color: var(--btn-text);
  border: none;
  border-radius: 2.5rem;
  padding: 0.4rem 1rem;
  cursor: pointer;
  font-size: 0.9rem;
  transition: transform 0.2s ease, opacity 0.2s ease;
  white-space: nowrap;
}

.search-box button:hover {
  transform: scale(1.05);
  opacity: 0.9;
}

/* 主题开关 & 菜单按钮 */
.theme-toggle, .menu-toggle {
  background: var(--bg-soft);
  border: 1px solid var(--border-color);
  border-radius: 2rem;
  padding: 0.4rem 1rem;
  cursor: pointer;
  color: var(--text-primary);
  font-size: 0.9rem;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.theme-toggle:hover, .menu-toggle:hover {
  background: var(--chip-bg);
  border-color: var(--chip-border);
  transform: translateY(-1px);
}

.menu-toggle {
  display: none;
}

/* ===== 移动端导航 ===== */
@media (max-width: 768px) {
  .nav-links {
    display: none;
    flex-direction: column;
    background: var(--bg);
    position: absolute;
    top: 70px;
    left: 0;
    width: 100%;
    padding: 1.5rem 2rem;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    border-bottom: 1px solid var(--border-color);
    backdrop-filter: blur(20px);
  }
  .nav-links.open {
    display: flex;
    animation: fadeIn 0.3s ease;
  }
  .menu-toggle {
    display: block;
  }
  .search-box {
    max-width: 120px;
  }
  .nav-actions {
    gap: 0.5rem;
  }
}

@media (max-width: 480px) {
  .search-box {
    display: none;
  }
  .logo {
    font-size: 1.3rem;
  }
}

/* ===== 按钮 ===== */
.btn {
  display: inline-block;
  background: var(--btn-bg);
  color: var(--btn-text);
  padding: 0.7rem 2rem;
  border-radius: 2.5rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 4px 15px rgba(79, 70, 229, 0.2);
  position: relative;
  overflow: hidden;
  font-size: 0.95rem;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left 0.5s ease;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(79, 70, 229, 0.3);
  color: var(--btn-text);
  text-decoration: none;
}

.btn:hover::before {
  left: 100%;
}

/* Hero 按钮 */
.hero .btn {
  background: linear-gradient(135deg, #f59e0b, #fbbf24);
  color: #1e1b4b;
  box-shadow: 0 4px 20px rgba(245, 158, 11, 0.3);
  animation: pulseGlow 3s ease-in-out infinite;
}

.hero .btn:hover {
  transform: translateY(-3px) scale(1.02);
  box-shadow: 0 8px 30px rgba(245, 158, 11, 0.4);
}

/* ===== Hero Banner ===== */
.hero {
  background: linear-gradient(
    135deg, 
    var(--hero-grad-start) 0%, 
    var(--hero-grad-mid) 40%, 
    var(--hero-grad-end) 100%
  );
  color: white;
  padding: clamp(3rem, 8vw, 6rem) 0 clamp(4rem, 10vw, 7rem);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  width: 500px;
  height: 500px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(139, 92, 246, 0.3), transparent 70%);
  top: -100px;
  right: -100px;
  animation: float 8s ease-in-out infinite;
}

.hero::after {
  content: '';
  position: absolute;
  width: 300px;
  height: 300px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(59, 130, 246, 0.2), transparent 70%);
  bottom: -50px;
  left: 10%;
  animation: float 10s ease-in-out infinite reverse;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: var(--hero-overlay);
  backdrop-filter: blur(2px);
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 800px;
  animation: fadeInUp 1s ease both;
}

.hero-content h1 {
  color: white;
  font-size: clamp(2.2rem, 5vw, 3.5rem);
  margin-bottom: 1rem;
  line-height: 1.2;
  text-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.hero-content p {
  color: rgba(255, 255, 255, 0.85);
  font-size: clamp(1rem, 2vw, 1.3rem);
  margin-bottom: 0.8rem;
  text-shadow: 0 1px 10px rgba(0, 0, 0, 0.2);
}

.hero-content p:first-of-type {
  font-size: clamp(1.2rem, 3vw, 1.6rem);
  font-weight: 600;
  color: #e0e7ff;
  letter-spacing: 0.02em;
}

.hero-content .btn {
  margin-top: 1.5rem;
}

/* ===== 卡片网格 ===== */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin: 2.5rem 0;
}

.card {
  background: var(--card-bg);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-radius: 1.2rem;
  padding: 1.8rem;
  border: 1px solid var(--card-border);
  box-shadow: var(--shadow);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, #4f46e5, #a855f7, #4f46e5);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s ease;
}

.card:hover {
  transform: translateY(-8px) scale(1.02);
  box-shadow: var(--shadow-hover);
  border-color: var(--link-color);
}

.card:hover::before {
  transform: scaleX(1);
}

.card h3 {
  margin-top: 0;
  margin-bottom: 1rem;
  font-size: 1.3rem;
}

.card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: 0;
}

.card h4 {
  color: var(--heading-color);
  font-weight: 700;
  margin-bottom: 0.5rem;
}

/* ===== 文章列表 ===== */
.article-item {
  border-bottom: 1px solid var(--border-color);
  padding: 1.8rem 0;
  transition: padding-left 0.3s ease, background 0.3s ease;
  border-radius: 0.8rem;
  padding-left: 1rem;
  padding-right: 1rem;
}

.article-item:hover {
  background: var(--bg-soft);
  padding-left: 1.5rem;
  border-radius: 1rem;
}

.article-item h4 {
  font-size: clamp(1.1rem, 2vw, 1.4rem);
  margin-bottom: 0.5rem;
  color: var(--heading-color);
  transition: color 0.2s ease;
}

.article-item:hover h4 {
  background: linear-gradient(135deg, #4f46e5, #a855f7);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.article-item .date {
  color: var(--text-muted);
  font-size: 0.85rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.article-item .date::before {
  content: '📅';
  font-size: 0.8rem;
}

.article-item p {
  margin-top: 0.5rem;
  color: var(--text-secondary);
}

.read-more {
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  transition: gap 0.2s ease;
  color: var(--link-color);
}

.read-more:hover {
  gap: 0.6rem;
  text-decoration: none;
}

/* ===== FAQ ===== */
.faq-box {
  margin: 1rem 0;
  border: 1px solid var(--border-color);
  border-radius: 1rem;
  padding: 0.5rem 1.5rem;
  background: var(--card-bg);
  backdrop-filter: blur(8px);
  transition: all 0.3s ease;
  cursor: pointer;
  overflow: hidden;
}

.faq-box:hover {
  border-color: var(--link-color);
  box-shadow: var(--shadow);
}

.faq-question {
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--heading-color);
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 0;
  user-select: none;
  gap: 1rem;
}

.faq-question span {
  font-size: 1.5rem;
  font-weight: 300;
  transition: transform 0.3s ease;
  color: var(--link-color);
  flex-shrink: 0;
}

.faq-answer {
  color: var(--text-primary);
  padding-bottom: 1rem;
  display: none;
  animation: fadeIn 0.3s ease;
  line-height: 1.8;
  border-top: 1px solid var(--border-color);
  padding-top: 1rem;
}

.faq-box.open {
  border-color: var(--link-color);
  box-shadow: var(--shadow);
}

.faq-box.open .faq-answer {
  display: block;
}

.faq-box.open .faq-question span {
  transform: rotate(45deg);
}

/* ===== Footer ===== */
footer {
  background: var(--footer-bg);
  color: var(--footer-text);
  padding: 3.5rem 0 2rem;
  margin-top: 5rem;
  position: relative;
  overflow: hidden;
}

footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(99, 102, 241, 0.5), transparent);
}

footer a {
  color: var(--footer-link);
  transition: color 0.2s ease;
}

footer a:hover {
  color: #ffffff;
  text-decoration: none;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2.5rem;
}

.footer-grid h4 {
  color: #ffffff !important;
  margin-bottom: 1rem;
  font-size: 1.1rem;
  position: relative;
}

.footer-grid h4::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 30px;
  height: 2px;
  background: linear-gradient(90deg, #4f46e5, #a855f7);
}

.footer-grid p {
  color: var(--footer-text);
  font-size: 0.9rem;
}

.footer-bottom {
  border-top: 1px solid rgba(148, 163, 184, 0.15);
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  font-size: 0.85rem;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  color: var(--footer-text);
}

.footer-bottom span {
  display: inline-block;
}

/* ===== 返回顶部 ===== */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  background: var(--btn-bg);
  color: var(--btn-text);
  padding: 0.8rem 1.1rem;
  border-radius: 50%;
  border: none;
  cursor: pointer;
  font-size: 1.2rem;
  display: none;
  z-index: 1000;
  transition: all 0.3s ease;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
  opacity: 0;
  transform: translateY(20px);
}

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

.back-to-top:hover {
  transform: translateY(-4px) scale(1.1);
  box-shadow: 0 8px 25px rgba(79, 70, 229, 0.3);
}

/* ===== 表格 ===== */
.content-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  margin: 2rem 0;
  border-radius: 1rem;
  overflow: hidden;
  box-shadow: var(--shadow);
}

.content-table th,
.content-table td {
  border: 1px solid var(--border-color);
  padding: 0.9rem 1.2rem;
  text-align: left;
  color: var(--text-primary);
  transition: background 0.2s ease;
}

.content-table th {
  background: var(--bg-soft);
  font-weight: 700;
  text-transform: uppercase;
  font-size: 0.85rem;
  letter-spacing: 0.05em;
}

.content-table tr:hover td {
  background: var(--bg-soft);
}

/* ===== 标签 chips ===== */
[style*="background:#dbeafe"] {
  background: var(--chip-bg) !important;
  border: 1px solid var(--chip-border) !important;
  color: var(--text-primary) !important;
  padding: 0.4rem 1.2rem !important;
  border-radius: 2rem !important;
  font-size: 0.9rem;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  transition: all 0.3s ease;
  cursor: default;
}

[style*="background:#dbeafe"]:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

/* ===== 有序列表 ===== */
ol {
  margin-left: 1.5rem;
  color: var(--text-primary);
}

ol li {
  padding: 0.4rem 0;
  line-height: 1.8;
  position: relative;
  list-style: none;
  counter-increment: custom;
  padding-left: 2.5rem;
}

ol li::before {
  content: counter(custom);
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 1.8rem;
  height: 1.8rem;
  background: var(--btn-bg);
  color: var(--btn-text);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  font-weight: 700;
  box-shadow: 0 2px 8px rgba(79, 70, 229, 0.2);
}

ol {
  counter-reset: custom;
}

/* ===== 图片占位样式 ===== */
.svg-img {
  background: linear-gradient(135deg, var(--bg-soft), var(--border-color));
  border-radius: 0.8rem;
  width: 100%;
  height: auto;
  display: block;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.svg-img:hover {
  transform: scale(1.02);
  box-shadow: var(--shadow);
}

/* ===== 强调文本 ===== */
strong {
  color: var(--heading-color);
  font-weight: 700;
}

/* ===== 链接区块 ===== */
#contact p {
  line-height: 2.2;
}

#contact p strong {
  display: inline-block;
  margin-bottom: 0.3rem;
}

/* ===== 章节间距优化 ===== */
section {
  padding: 1rem 0 2rem;
}

section + section {
  border-top: 1px solid var(--border-color);
  margin-top: 2rem;
}

/* ===== 响应式增强 ===== */
@media (max-width: 1024px) {
  .grid {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  }
}

@media (max-width: 768px) {
  h1 {
    font-size: 2rem;
  }
  h2 {
    font-size: 1.6rem;
  }
  .hero {
    padding: 3rem 0 4rem;
  }
  .hero h1 {
    font-size: 2rem;
  }
  .hero-content p {
    font-size: 1rem;
  }
  .nav-inner {
    height: 60px;
  }
  .article-item {
    padding: 1.2rem 0.8rem;
  }
  .article-item:hover {
    padding-left: 1rem;
  }
  .back-to-top {
    bottom: 1.5rem;
    right: 1.5rem;
    padding: 0.7rem 1rem;
  }
  .footer-bottom {
    flex-direction: column;
    gap: 0.5rem;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 1rem;
  }
  .card {
    padding: 1.2rem;
  }
  .faq-box {
    padding: 0.3rem 1rem;
  }
  .btn {
    padding: 0.6rem 1.5rem;
    font-size: 0.9rem;
  }
}

/* ===== 无障碍：减少动态效果 ===== */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* ===== 打印样式 ===== */
@media print {
  .navbar,
  .back-to-top,
  .hero .btn,
  .theme-toggle,
  .menu-toggle,
  .search-box {
    display: none !important;
  }
  body {
    background: white;
    color: black;
  }
  a {
    color: black;
  }
}