/* ===== 基础重置与变量 ===== */
:root {
  --bg-primary: #F8F5F0;
  --bg-secondary: #F0EBE3;
  --bg-card: #FFFDF9;
  --color-primary: #8B6F47;
  --color-dark: #3D2B1F;
  --color-gold: #C4A265;
  --color-gold-light: #D9C9A5;
  --color-text: #2C2420;
  --color-text-secondary: #6B5E54;
  --color-text-muted: #9E9186;
  --color-border: #E8E0D4;
  --color-accent: #B8956A;
  --font-serif: "Noto Serif SC", "Source Han Serif SC", "SimSun", "STSong", serif;
  --font-sans: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --shadow-sm: 0 1px 3px rgba(61, 43, 31, 0.06);
  --shadow-md: 0 4px 20px rgba(61, 43, 31, 0.08);
  --shadow-lg: 0 8px 40px rgba(61, 43, 31, 0.12);
  --radius: 8px;
  --radius-lg: 16px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background-color: var(--bg-primary);
  line-height: 1.8;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

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

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

/* ===== 容器 ===== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 100px 0;
}

.section-title {
  font-family: var(--font-serif);
  font-size: 2.4rem;
  font-weight: 600;
  color: var(--color-dark);
  text-align: center;
  margin-bottom: 16px;
  letter-spacing: 4px;
}

.section-subtitle {
  font-size: 1rem;
  color: var(--color-text-secondary);
  text-align: center;
  margin-bottom: 60px;
  letter-spacing: 2px;
}

/* ===== 导航栏 ===== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: rgba(248, 245, 240, 0.92);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border);
  transition: var(--transition);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-text {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-dark);
  letter-spacing: 2px;
}

.logo-tag {
  font-size: 0.7rem;
  color: var(--color-text-muted);
  letter-spacing: 1px;
  border-left: 1px solid var(--color-border);
  padding-left: 12px;
  line-height: 1.4;
}

.nav-links {
  display: flex;
  gap: 40px;
  list-style: none;
}

.nav-links a {
  font-size: 0.95rem;
  color: var(--color-text-secondary);
  letter-spacing: 1px;
  position: relative;
  padding: 4px 0;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--color-gold);
  transition: var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--color-dark);
}

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

.nav-mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  cursor: pointer;
  padding: 8px;
}

.nav-mobile-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-dark);
  transition: var(--transition);
}

/* ===== 页脚 ===== */
.footer {
  background: var(--color-dark);
  color: rgba(255, 255, 255, 0.7);
  padding: 60px 0 30px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand .logo-text {
  color: var(--color-gold-light);
  margin-bottom: 16px;
}

.footer-brand p {
  font-size: 0.9rem;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.6);
}

.footer-title {
  font-size: 1rem;
  color: var(--color-gold-light);
  margin-bottom: 20px;
  letter-spacing: 2px;
  font-weight: 500;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 12px;
}

.footer-links a {
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.6);
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--color-gold);
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 24px;
  text-align: center;
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.4);
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 36px;
  font-size: 0.95rem;
  letter-spacing: 2px;
  border-radius: var(--radius);
  cursor: pointer;
  transition: var(--transition);
  border: none;
  font-family: var(--font-sans);
}

.btn-primary {
  background: var(--color-dark);
  color: #fff;
}

.btn-primary:hover {
  background: var(--color-primary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

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

.btn-outline:hover {
  background: var(--color-dark);
  color: #fff;
}

.btn-gold {
  background: var(--color-gold);
  color: #fff;
}

.btn-gold:hover {
  background: var(--color-primary);
  transform: translateY(-2px);
}

/* ===== 卡片 ===== */
.card {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  padding: 36px;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-border);
  transition: var(--transition);
}

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

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

.animate {
  animation: fadeInUp 0.8s ease forwards;
}

.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }
.delay-3 { animation-delay: 0.3s; }
.delay-4 { animation-delay: 0.4s; }

/* ===== 滚动条 ===== */
::-webkit-scrollbar {
  width: 8px;
}

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

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

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

/* ===== 响应式 ===== */
@media (max-width: 1024px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    background: rgba(248, 245, 240, 0.98);
    flex-direction: column;
    gap: 0;
    padding: 20px 24px;
    border-bottom: 1px solid var(--color-border);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: var(--transition);
  }

  .nav-links.active {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }

  .nav-links li {
    border-bottom: 1px solid var(--color-border);
  }

  .nav-links a {
    display: block;
    padding: 16px 0;
  }

  .nav-mobile-toggle {
    display: flex;
  }

  .section {
    padding: 60px 0;
  }

  .section-title {
    font-size: 1.8rem;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .logo-tag {
    display: none;
  }
}

/* ===== 企业微信二维码卡片 ===== */
/* 色调取自本站色系：米黄底（--bg-secondary 家族）+ 金棕描边（--color-gold-light） */
.wecom-card {
  display: flex;
  align-items: center;
  gap: 20px;
  max-width: 460px;
  padding: 22px 26px;
  background: linear-gradient(135deg, #FDFBF4 0%, #F3E9D7 100%);
  border: 1px solid #E6D7B8;
  border-radius: var(--radius-lg);
  box-shadow: 0 6px 24px rgba(139, 111, 71, 0.10);
  text-align: left;
}

/* CTA 深色区里的用法：居中、与按钮拉开距离 */
.wecom-card--cta {
  margin: 36px auto 0;
}

.wecom-card-qr {
  flex: 0 0 auto;
  width: 128px;
  height: 128px;
  padding: 7px;
  background: #fff;
  border: 1px solid #EDE3CD;
  border-radius: 12px;
  box-shadow: 0 2px 10px rgba(139, 111, 71, 0.08);
}

/* 二维码本体永远保持纯黑模块、四周留白 —— 颜色一律做在卡片上，
   不要给二维码上色，会降低扫码成功率 */
.wecom-card-qr img {
  display: block;
  width: 100%;
  height: 100%;
}

.wecom-card-body {
  min-width: 0;
}

/* 以下三条统一带 .wecom-card 前缀提升优先级：
   CTA 深色区里存在 .cta-box p / .cta-box h2 这类规则，
   裸类选择器会被它们盖掉（文字被染白、下方多出 36px 间距）。 */
.wecom-card .wecom-card-tag {
  display: inline-block;
  padding: 3px 12px;
  margin: 0 0 10px;
  font-size: 0.7rem;
  letter-spacing: 2px;
  color: var(--color-primary);
  background: rgba(196, 162, 101, 0.16);
  border: 1px solid rgba(196, 162, 101, 0.35);
  border-radius: 999px;
}

.wecom-card .wecom-card-title {
  margin: 0 0 8px;
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 500;
  letter-spacing: 1px;
  color: var(--color-dark);
}

.wecom-card .wecom-card-title .wecom-card-name {
  color: var(--color-primary);
}

.wecom-card .wecom-card-desc {
  margin: 0;
  font-size: 0.82rem;
  line-height: 1.75;
  color: var(--color-text-secondary);
}

/* CTA 深色底上的「或」分割线 */
.cta-divider {
  display: flex;
  align-items: center;
  gap: 14px;
  max-width: 340px;
  margin: 36px auto 0;
  font-size: 0.78rem;
  letter-spacing: 2px;
  color: rgba(255, 255, 255, 0.45);
}

.cta-divider::before,
.cta-divider::after {
  content: '';
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(217, 201, 165, 0.5), transparent);
}

/* 联系页左栏里的用法：与上方联系条目拉开距离 */
.contact-info .wecom-card {
  margin-top: 32px;
}

@media (max-width: 560px) {
  .wecom-card {
    flex-direction: column;
    gap: 16px;
    max-width: 340px;
    padding: 24px 20px;
    margin-left: auto;
    margin-right: auto;
    text-align: center;
  }

  /* 手机端把二维码放大，方便扫码 */
  .wecom-card-qr {
    width: 156px;
    height: 156px;
  }

  .cta-divider {
    margin-top: 28px;
  }
}

/* ===== 回到顶部 =====
   全站共用（style.css 被 5 个页面引用），按钮由 main.js 动态注入，见 main.js 末尾。
   做法参照主流网站：滚动超过一屏后淡入，点击平滑回到顶部，并带一圈阅读进度环。
   环形进度用 SVG 描边虚线偏移实现：周长 = 2πr = 2 × π × 24 ≈ 150.8，
   CSS 与 JS 里用的是同一个常量，改半径要两处一起改。 */
.back-to-top {
  position: fixed;
  right: 28px;
  bottom: 28px;
  bottom: calc(28px + env(safe-area-inset-bottom, 0px));
  z-index: 90;
  width: 48px;
  height: 48px;
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--color-border);
  border-radius: 50%;
  background: var(--bg-card);
  color: var(--color-primary);
  box-shadow: var(--shadow-md);
  cursor: pointer;
  font: inherit;
  opacity: 0;
  visibility: hidden;
  transform: translateY(14px);
  transition: opacity 0.3s ease, visibility 0.3s ease, transform 0.3s ease,
              background-color 0.3s ease, color 0.3s ease, box-shadow 0.3s ease;
  -webkit-tap-highlight-color: transparent;
}

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

.back-to-top:hover,
.back-to-top:focus-visible {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #FFFDF9;
  box-shadow: var(--shadow-lg);
}

.back-to-top:focus-visible {
  outline: 2px solid var(--color-gold);
  outline-offset: 3px;
}

.back-to-top .btt-ring {
  position: absolute;
  inset: -1px;
  width: calc(100% + 2px);
  height: calc(100% + 2px);
  transform: rotate(-90deg);
  pointer-events: none;
}

.back-to-top .btt-ring circle {
  fill: none;
  stroke: var(--color-gold);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-dasharray: 150.8;
  stroke-dashoffset: 150.8;
  transition: stroke-dashoffset 0.15s linear;
}

.back-to-top .btt-arrow {
  width: 20px;
  height: 20px;
  display: block;
}

/* 手机端：按钮略小、更贴边，尺寸仍 ≥44px（触控舒适区） */
@media (max-width: 560px) {
  .back-to-top {
    right: 16px;
    bottom: 20px;
    bottom: calc(20px + env(safe-area-inset-bottom, 0px));
    width: 44px;
    height: 44px;
  }

  .back-to-top .btt-arrow {
    width: 18px;
    height: 18px;
  }
}

/* 用户在系统里关了动效：不要位移与平滑滚动，直接瞬移 */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .back-to-top {
    transform: none;
    transition: opacity 0.01s linear, visibility 0.01s linear;
  }

  .back-to-top .btt-ring circle {
    transition: none;
  }
}

@media print {
  .back-to-top {
    display: none !important;
  }
}