/* ============================================
   以诚文化官网 — 全局样式
   气质：东方人文温度 × 学术研究理性
   ============================================ */

/* ---------- CSS 变量：Design Tokens ---------- */
:root {
  /* 色彩体系 */
  --color-rice-paper: #FBF3E7;       /* 米纸 - 页面底色 */
  --color-card-rice: #FFF9F1;        /* 卡片米 - 卡片底色 */
  --color-ink: #31251B;              /* 墨色 - 主文字 */
  --color-ink-light: #5A4A3D;        /* 浅墨 - 次要文字 */
  --color-ink-muted: #8B7D6B;        /* 灰墨 - 辅助文字 */
  --color-ochre: #C96F3D;            /* 赭石 - 强调色 */
  --color-seal-red: #B8342C;         /* 印章红 - 品牌强调 */
  --color-soft-green: #7E9F7A;       /* 柔和绿 - 正向状态 */
  --color-function-orange: #E8743B;  /* 功能橙 - 按钮交互 */
  --color-deep-blue: #1E3A5F;        /* 深蓝 - 信息区 */
  --color-line-light: #E8DFD0;       /* 浅灰线 - 分割线 */
  --color-line-medium: #D9CDB8;      /* 中线 - 次级边框 */
  --color-white: #FFFFFF;

  /* 字体 */
  --font-serif-cn: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "STSong", "SimSun", serif;
  --font-sans: "Inter", system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-title: "Noto Serif SC", "Source Han Serif SC", "KaiTi", "STKaiti", serif;

  /* 间距 */
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2.5rem;
  --space-xl: 4rem;
  --space-2xl: 6rem;
  --space-3xl: 8rem;

  /* 容器 */
  --container-max: 1200px;
  --container-narrow: 860px;
  --section-padding-y: 5rem;
  --section-padding-y-mobile: 3rem;

  /* 圆角 */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;

  /* 阴影 */
  --shadow-sm: 0 1px 3px rgba(49, 37, 27, 0.06);
  --shadow-md: 0 4px 16px rgba(49, 37, 27, 0.08);
  --shadow-lg: 0 12px 32px rgba(49, 37, 27, 0.12);

  /* 动效 */
  --transition-base: 300ms ease-out;
  --transition-slow: 600ms ease-out;
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);

  /* 字体大小 */
  --fs-xs: 0.75rem;
  --fs-sm: 0.875rem;
  --fs-base: 1rem;
  --fs-md: 1.125rem;
  --fs-lg: 1.375rem;
  --fs-xl: 1.75rem;
  --fs-2xl: 2.25rem;
  --fs-3xl: 3rem;
  --fs-4xl: 4rem;
}

/* ---------- Reset & Base ---------- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-serif-cn);
  font-size: var(--fs-base);
  line-height: 1.8;
  color: var(--color-ink);
  background-color: var(--color-rice-paper);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  letter-spacing: 0.02em;
  min-height: 100vh;
}

/* 宣纸纹理背景（纯CSS模拟）*/
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: -1;
  background-image:
    radial-gradient(ellipse at 20% 30%, rgba(201, 111, 61, 0.03) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 70%, rgba(184, 52, 44, 0.02) 0%, transparent 50%);
  opacity: 1;
}

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

a {
  color: var(--color-ochre);
  text-decoration: none;
  transition: color var(--transition-base);
}

a:hover {
  color: var(--color-seal-red);
}

ul, ol {
  list-style: none;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-title);
  font-weight: 600;
  line-height: 1.4;
  color: var(--color-ink);
  letter-spacing: 0.04em;
}

/* ---------- 容器 ---------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.container-narrow {
  width: 100%;
  max-width: var(--container-narrow);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

/* ---------- 章节标题 ---------- */
.section {
  padding: var(--section-padding-y) 0;
}

.section-heading {
  text-align: center;
  margin-bottom: var(--space-xl);
}

.section-title {
  font-size: var(--fs-2xl);
  font-family: var(--font-title);
  color: var(--color-ink);
  position: relative;
  display: inline-block;
  padding-bottom: var(--space-sm);
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 2px;
  background: var(--color-ochre);
}

.section-subtitle {
  font-size: var(--fs-sm);
  color: var(--color-ink-muted);
  margin-top: var(--space-sm);
  letter-spacing: 0.2em;
  font-family: var(--font-sans);
}

.section-lead {
  font-size: var(--fs-base);
  color: var(--color-ochre);
  margin-top: var(--space-md);
  font-family: var(--font-title);
  font-style: italic;
  letter-spacing: 0.05em;
  max-width: 640px;
  margin-left: auto;
  margin-right: auto;
  line-height: 1.8;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 2rem;
  font-family: var(--font-serif-cn);
  font-size: var(--fs-base);
  letter-spacing: 0.1em;
  border: none;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-base);
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary {
  background-color: var(--color-function-orange);
  color: var(--color-white);
}

.btn-primary:hover {
  background-color: var(--color-seal-red);
  color: var(--color-white);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-outline {
  background-color: transparent;
  color: var(--color-ochre);
  border: 1px solid var(--color-ochre);
}

.btn-outline:hover {
  background-color: var(--color-ochre);
  color: var(--color-white);
}

.btn-dark {
  background-color: var(--color-deep-blue);
  color: var(--color-white);
}

.btn-dark:hover {
  background-color: #2a4d7a;
  color: var(--color-white);
}

/* ---------- 卡片 ---------- */
.card {
  background-color: var(--color-card-rice);
  border: 1px solid var(--color-line-light);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  transition: all var(--transition-base);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-line-medium);
}

/* ---------- 顶部导航 ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background-color: rgba(251, 243, 231, 0.92);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-line-light);
  transition: all var(--transition-base);
}

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

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  text-decoration: none;
  color: var(--color-ink);
}

/* 印章 Logo (真实印章图片) */
.seal-logo {
  width: 44px;
  height: 44px;
  position: relative;
  transform: rotate(-2deg);
  flex-shrink: 0;
}

.seal-logo img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}

/* logo-seal 兼容类名 */
.logo-seal {
  width: 44px;
  height: 44px;
  display: block;
  position: relative;
  transform: rotate(-2deg);
  flex-shrink: 0;
}

.logo-seal img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brand-name {
  font-family: var(--font-title);
  font-size: var(--fs-lg);
  font-weight: 600;
  color: var(--color-ink);
}

.brand-slogan {
  font-size: var(--fs-xs);
  color: var(--color-ink-muted);
  letter-spacing: 0.15em;
  font-family: var(--font-sans);
}

/* 以诚品牌Logo */
.logo-brand {
  display: flex;
  align-items: center;
}
.logo-brand img {
  height: 40px;
  width: auto;
  display: block;
}

.footer-brand-logo {
  width: 180px;
  height: auto;
  margin-bottom: var(--space-sm);
  display: block;
}

/* 导航菜单 */
.main-nav {
  display: flex;
  align-items: center;
}

.nav-list {
  display: flex;
  gap: var(--space-md);
  list-style: none;
}

.nav-item {
  position: relative;
}

.nav-link {
  display: block;
  padding: 0.5rem 0.25rem;
  color: var(--color-ink);
  font-size: var(--fs-sm);
  letter-spacing: 0.1em;
  text-decoration: none;
  transition: color var(--transition-base);
  position: relative;
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 2px;
  background-color: var(--color-ochre);
  transition: all var(--transition-base);
  transform: translateX(-50%);
}

.nav-link:hover,
.nav-link.active {
  color: var(--color-ochre);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

/* 下拉小箭头 */
.nav-caret {
  display: inline-block;
  width: 0;
  height: 0;
  margin-left: 4px;
  border-left: 4px solid transparent;
  border-right: 4px solid transparent;
  border-top: 5px solid currentColor;
  vertical-align: middle;
  transition: transform var(--transition-base);
  opacity: 0.7;
}

/* 子菜单（桌面端） */
.submenu {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(8px);
  min-width: 180px;
  list-style: none;
  background-color: var(--color-card-rice);
  border: 1px solid var(--color-line-light);
  border-radius: var(--radius-md);
  padding: var(--space-xs) 0;
  box-shadow: var(--shadow-md);
  opacity: 0;
  visibility: hidden;
  transition: all 0.25s ease-out;
  z-index: 102;
}

.nav-item.has-children:hover .submenu {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

.subnav-item {
  width: 100%;
}

.subnav-link {
  display: block;
  padding: 0.6rem 1.25rem;
  color: var(--color-ink);
  font-size: var(--fs-sm);
  text-decoration: none;
  transition: all var(--transition-base);
  white-space: nowrap;
  border-left: 2px solid transparent;
}

.subnav-link:hover,
.subnav-link.active {
  color: var(--color-ochre);
  background-color: rgba(201, 111, 61, 0.06);
  border-left-color: var(--color-ochre);
}

/* 品牌 Logo 图片 */
.brand-logo-img {
  height: clamp(32px, 4vw, 40px);
  width: auto;
  display: block;
}

/* 页脚品牌 Logo */
.footer-brand-logo {
  width: 160px;
  max-width: 100%;
  height: auto;
  display: block;
  margin-bottom: var(--space-sm);
}  height: 36px;
  width: auto;
  display: block;
}

/* 移动端菜单按钮 */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  flex-direction: column;
  gap: 5px;
  z-index: 101;
}

.menu-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-ink);
  transition: all var(--transition-base);
  border-radius: 1px;
}

.menu-toggle.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.menu-toggle.open span:nth-child(2) {
  opacity: 0;
}

.menu-toggle.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ---------- Hero 首屏 ---------- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  padding-top: 72px;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 20%;
  left: 50%;
  transform: translateX(-50%);
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(201, 111, 61, 0.08) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

.hero-content {
  text-align: center;
  max-width: 800px;
  padding: 0 var(--space-md);
  z-index: 1;
}

/* 首屏以诚品牌Logo */
.hero-brand-logo {
  margin-bottom: var(--space-md);
  opacity: 0;
  animation: fadeInDown 800ms 100ms ease-out forwards;
}
.hero-brand-logo img {
  height: clamp(48px, 9vw, 80px);
  width: auto;
  display: block;
  margin: 0 auto;
}

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.hero-seal {
  width: 140px;
  height: 140px;
  margin: 0 auto var(--space-lg);
  position: relative;
  opacity: 0;
  transform: scale(1.5);
  animation: seal-stamp 1.2s var(--ease-out) 0.3s forwards;
}

.hero-seal img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
  filter: drop-shadow(2px 2px 4px rgba(184, 52, 44, 0.15));
}

@keyframes seal-stamp {
  0% {
    opacity: 0;
    transform: scale(1.5) rotate(-5deg);
  }
  60% {
    opacity: 1;
    transform: scale(0.95) rotate(0);
  }
  100% {
    opacity: 1;
    transform: scale(1) rotate(-2deg);
  }
}

.hero-title {
  font-size: var(--fs-4xl);
  font-family: var(--font-title);
  color: var(--color-ink);
  letter-spacing: 0.15em;
  margin-bottom: var(--space-md);
  opacity: 0;
  transform: translateY(20px);
  animation: fade-up 0.8s var(--ease-out) 0.8s forwards;
}

.hero-subtitle {
  font-size: var(--fs-md);
  color: var(--color-ink-light);
  letter-spacing: 0.2em;
  margin-bottom: var(--space-lg);
  font-family: var(--font-sans);
  opacity: 0;
  transform: translateY(20px);
  animation: fade-up 0.8s var(--ease-out) 1s forwards;
}

/* 滚动金句 */
.hero-quote-wrapper {
  position: relative;
  height: 60px;
  margin-bottom: var(--space-xl);
  opacity: 0;
  animation: fade-in 0.8s var(--ease-out) 1.2s forwards;
}

.hero-quote {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  font-size: var(--fs-lg);
  color: var(--color-ochre);
  font-family: var(--font-title);
  font-style: italic;
  letter-spacing: 0.1em;
  opacity: 0;
  transition: opacity 1.2s ease-in-out;
}

.hero-quote.active {
  opacity: 1;
}

.hero-tagline {
  display: inline-block;
  padding: var(--space-sm) var(--space-lg);
  background-color: var(--color-function-orange);
  color: var(--color-white);
  font-size: var(--fs-sm);
  letter-spacing: 0.15em;
  font-family: var(--font-sans);
  border-radius: 2px;
  opacity: 0;
  transform: translateY(20px);
  animation: fade-up 0.8s var(--ease-out) 1.4s forwards;
}
.hero-positioning {
  margin-top: var(--space-sm);
  font-size: var(--fs-base);
  color: var(--color-ink-light);
  letter-spacing: 0.08em;
  font-family: var(--font-title);
  opacity: 0;
  transform: translateY(20px);
  animation: fade-up 0.8s var(--ease-out) 1.6s forwards;
}

@keyframes fade-up {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fade-in {
  to {
    opacity: 1;
  }
}

/* 滚动提示 */
.scroll-hint {
  position: absolute;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  color: var(--color-ink-muted);
  font-size: var(--fs-xs);
  letter-spacing: 0.2em;
  opacity: 0;
  animation: fade-in 0.8s var(--ease-out) 2s forwards;
}

.scroll-hint-arrow {
  width: 1px;
  height: 40px;
  background: linear-gradient(to bottom, var(--color-ink-muted), transparent);
  animation: scroll-arrow 2s ease-in-out infinite;
}

@keyframes scroll-arrow {
  0%, 100% { opacity: 0.3; transform: scaleY(0.5); }
  50% { opacity: 1; transform: scaleY(1); }
}

/* ---------- 滚动出现动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity var(--transition-slow), transform var(--transition-slow);
}

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

/* ---------- 固定浮层按钮 ---------- */
.floating-action {
  position: fixed;
  right: 1.5rem;
  bottom: 2rem;
  z-index: 90;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.floating-btn {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background-color: var(--color-seal-red);
  color: var(--color-rice-paper);
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--fs-xs);
  font-family: var(--font-title);
  letter-spacing: 0.05em;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
  text-decoration: none;
  text-align: center;
  line-height: 1.2;
}

.floating-btn:hover {
  background-color: var(--color-function-orange);
  color: var(--color-white);
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

/* ---------- 页脚 ---------- */
.site-footer {
  background-color: var(--color-deep-blue);
  color: rgba(255, 255, 255, 0.8);
  padding: var(--space-2xl) 0 var(--space-lg);
  margin-top: var(--space-2xl);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: var(--space-xl);
  margin-bottom: var(--space-xl);
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.footer-brand .seal-logo {
  background-color: var(--color-seal-red);
  color: var(--color-rice-paper);
}

.footer-brand-name {
  font-family: var(--font-title);
  font-size: var(--fs-lg);
  color: var(--color-white);
}

.footer-brand-slogan {
  color: rgba(255, 255, 255, 0.6);
  font-size: var(--fs-sm);
  letter-spacing: 0.1em;
}

.footer-heading {
  font-family: var(--font-title);
  font-size: var(--fs-md);
  color: var(--color-white);
  margin-bottom: var(--space-md);
  position: relative;
  padding-bottom: 0.5rem;
}

.footer-heading::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 30px;
  height: 1px;
  background-color: var(--color-ochre);
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-link {
  color: rgba(255, 255, 255, 0.7);
  font-size: var(--fs-sm);
  letter-spacing: 0.05em;
  text-decoration: none;
  transition: color var(--transition-base);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.footer-link::before {
  content: '';
  width: 4px;
  height: 4px;
  background-color: var(--color-ochre);
  border-radius: 50%;
  opacity: 0.6;
}

.footer-link:hover {
  color: var(--color-function-orange);
}

.footer-contact {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.footer-contact-item {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  font-size: var(--fs-sm);
  color: rgba(255, 255, 255, 0.7);
}

.footer-contact-icon {
  color: var(--color-ochre);
  flex-shrink: 0;
  margin-top: 2px;
}

.footer-social {
  display: flex;
  gap: var(--space-sm);
  margin-top: var(--space-md);
}

.social-icon {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background-color: rgba(255, 255, 255, 0.1);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255, 255, 255, 0.7);
  font-size: var(--fs-xs);
  text-decoration: none;
  transition: all var(--transition-base);
}

.social-icon:hover {
  background-color: var(--color-ochre);
  color: var(--color-white);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: var(--space-md);
  text-align: center;
  font-size: var(--fs-xs);
  color: rgba(255, 255, 255, 0.5);
  letter-spacing: 0.05em;
}

/* ---------- 页面头部（内页） ---------- */
.page-hero {
  padding: 140px 0 60px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.page-hero::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 2px;
  background-color: var(--color-ochre);
}

.page-title {
  font-size: var(--fs-3xl);
  font-family: var(--font-title);
  color: var(--color-ink);
  margin-bottom: var(--space-sm);
  letter-spacing: 0.1em;
}

.page-subtitle {
  font-size: var(--fs-sm);
  color: var(--color-ink-muted);
  letter-spacing: 0.2em;
  font-family: var(--font-sans);
}

/* 面包屑 */
.breadcrumb {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  margin-top: var(--space-md);
  font-size: var(--fs-xs);
  color: var(--color-ink-muted);
}

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

.breadcrumb-sep {
  color: var(--color-line-medium);
}

/* ---------- 响应式 ---------- */
@media (max-width: 968px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  :root {
    --section-padding-y: 3rem;
    --fs-4xl: 2.5rem;
    --fs-3xl: 2rem;
    --fs-2xl: 1.75rem;
  }

  .menu-toggle {
    display: flex;
  }

  .main-nav {
    position: fixed;
    top: 0;
    right: -100%;
    width: 80%;
    max-width: 320px;
    height: 100vh;
    background-color: var(--color-card-rice);
    flex-direction: column;
    padding: 80px var(--space-lg) var(--space-lg);
    transition: right var(--transition-base);
    box-shadow: -8px 0 24px rgba(49, 37, 27, 0.1);
  }

  .main-nav.open {
    right: 0;
  }

  .nav-list {
    flex-direction: column;
    gap: 0;
    width: 100%;
  }

  .nav-item {
    border-bottom: 1px solid var(--color-line-light);
  }

  .nav-link {
    padding: 1rem 0;
    font-size: var(--fs-base);
  }

  /* 移动端：子菜单 */
  .submenu {
    position: static;
    transform: none;
    opacity: 1;
    visibility: visible;
    box-shadow: none;
    border: none;
    background: transparent;
    padding: 0 0 0 var(--space-md);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-out;
    min-width: 0;
  }

  .nav-item.has-children.open .submenu {
    max-height: 500px;
  }

  .nav-item.has-children.open .nav-caret {
    transform: rotate(180deg);
  }

  .subnav-link {
    padding: 0.75rem 0;
    font-size: var(--fs-sm);
    border-left: none;
    color: var(--color-ink-light);
  }

  .subnav-link:hover,
  .subnav-link.active {
    background: transparent;
    border-left: none;
    color: var(--color-ochre);
  }

  .hero-title {
    font-size: var(--fs-3xl);
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }

  .floating-action {
    right: 1rem;
    bottom: 1.5rem;
  }

  .floating-btn {
    width: 48px;
    height: 48px;
    font-size: 11px;
  }

  .section {
    padding: 3rem 0;
  }
}

@media (max-width: 480px) {
  :root {
    --fs-4xl: 2rem;
    --fs-3xl: 1.75rem;
  }

  .container {
    padding: 0 1rem;
  }
}

/* ---------- 减少动效偏好 ---------- */
@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;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}

/* ---------- 辅助类 ---------- */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mt-xl { margin-top: var(--space-xl); }

.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.mb-xl { margin-bottom: var(--space-xl); }

.text-ochre { color: var(--color-ochre); }
.text-seal { color: var(--color-seal-red); }
.text-ink-light { color: var(--color-ink-light); }
.text-muted { color: var(--color-ink-muted); }

.bg-card { background-color: var(--color-card-rice); }
.bg-deep-blue { background-color: var(--color-deep-blue); }