:root {
  --ink: #1a2e35;
  --ink-soft: #3d5361;
  --ink-mute: #6b7d88;
  --teal: #1e5e6e;
  --teal-deep: #144149;
  --teal-soft: #4a8395;
  --amber: #c08552;
  --amber-deep: #a06a3c;
  --amber-soft: #e6b990;
  --paper: #f7f4ee;
  --paper-warm: #f0ebe1;
  --line: #e0d8c8;
  --line-soft: #ebe4d6;
  --gold: #b08d3c;
  --jade: #5a8c5a;
  --font-serif: "PingFang SC", "Microsoft YaHei", "微软雅黑", "Source Han Serif SC", "SimSun", "宋体", serif;
  --font-sans: "PingFang SC", "Microsoft YaHei", "微软雅黑", "Source Han Sans SC", "SimSun", "宋体", sans-serif;
  --max-w: 1100px;
  --nav-h: 64px;
  --radius: 4px;
  --radius-lg: 8px;
  --shadow-sm: 0 1px 3px rgba(26, 46, 53, 0.06);
  --shadow-md: 0 4px 16px rgba(26, 46, 53, 0.08);
  --shadow-lg: 0 12px 40px rgba(26, 46, 53, 0.12);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-h) + 24px);
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  color: var(--ink);
  background-color: var(--paper);
  line-height: 1.75;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  -webkit-overflow-scrolling: touch;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background-image:
    radial-gradient(circle at 20% 10%, rgba(192, 133, 82, 0.04) 0%, transparent 40%),
    radial-gradient(circle at 80% 80%, rgba(30, 94, 110, 0.04) 0%, transparent 40%);
}

a {
  color: var(--teal);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--amber-deep);
}

ul, ol {
  list-style: none;
}

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

h1, h2, h3, h4 {
  font-family: var(--font-serif);
  font-weight: 700;
  color: var(--ink);
  line-height: 1.3;
  letter-spacing: -0.01em;
}

p {
  margin-bottom: 1em;
}

p:last-child {
  margin-bottom: 0;
}

strong, b {
  font-weight: 600;
  color: var(--ink);
}

.container {
  width: 100%;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 32px;
  position: relative;
  z-index: 1;
}

main {
  position: relative;
  z-index: 1;
}

.notice-bar {
  background: linear-gradient(90deg, var(--amber) 0%, var(--amber-deep) 100%);
  color: #fff8ee;
  font-size: 13px;
  padding: 10px 0;
  text-align: center;
  letter-spacing: 0.02em;
  border-bottom: 1px solid var(--amber-deep);
}

.notice-bar strong {
  color: #fff;
  font-weight: 600;
  margin-right: 8px;
}

.notice-bar .notice-text {
  display: inline-block;
  max-width: 900px;
  padding: 0 16px;
}

.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--teal);
  box-shadow: var(--shadow-md);
  height: var(--nav-h);
  display: flex;
  align-items: center;
  border-bottom: 3px solid var(--amber);
}

.navbar .container {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-brand {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 18px;
  color: #fff;
  white-space: nowrap;
  letter-spacing: 0.02em;
  flex-shrink: 0;
}

.nav-brand .brand-mark {
  display: inline-block;
  width: 28px;
  height: 28px;
  background: var(--amber);
  color: #fff;
  text-align: center;
  line-height: 28px;
  border-radius: 2px;
  margin-right: 10px;
  font-size: 16px;
  vertical-align: middle;
}

.nav-menu {
  display: flex;
  gap: 4px;
  overflow-x: auto;
  scrollbar-width: none;
  flex: 1;
  scroll-behavior: smooth;
}

.nav-menu::-webkit-scrollbar {
  display: none;
}

.nav-scroll-hint {
  display: none;
  position: absolute;
  right: 8px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 16px;
  color: rgba(255, 255, 255, 0.4);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 0.4; }
  50% { opacity: 0.8; }
}

@media (max-width: 768px) {
  .nav-scroll-hint {
    display: block;
  }
}

.nav-menu a {
  display: block;
  color: rgba(255, 255, 255, 0.85);
  font-size: 13.5px;
  padding: 8px 12px;
  border-radius: var(--radius);
  white-space: nowrap;
  transition: all 0.2s ease;
  border: 1px solid transparent;
}

.nav-menu a:hover {
  color: #fff;
  background: rgba(255, 255, 255, 0.1);
}

.nav-menu a.active {
  color: #fff;
  background: var(--amber);
  border-color: var(--amber-deep);
}

.page-header {
  background: var(--paper-warm);
  padding: 64px 0 56px;
  text-align: center;
  border-bottom: 1px solid var(--line);
  position: relative;
  overflow: hidden;
}

.page-header::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(45deg, transparent 0, transparent 40px, rgba(30, 94, 110, 0.02) 40px, rgba(30, 94, 110, 0.02) 41px);
  pointer-events: none;
}

.page-header .container {
  position: relative;
}

.header-eyebrow {
  display: inline-block;
  font-family: var(--font-sans);
  font-size: 12px;
  letter-spacing: 0.3em;
  color: var(--amber-deep);
  text-transform: uppercase;
  margin-bottom: 20px;
  padding: 4px 14px;
  border: 1px solid var(--amber-soft);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.5);
}

.page-header h1 {
  font-size: 44px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.page-header .subtitle {
  font-family: var(--font-serif);
  font-size: 17px;
  color: var(--ink-soft);
  font-style: italic;
  margin-bottom: 24px;
}

.header-rule {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-top: 24px;
}

.header-rule::before,
.header-rule::after {
  content: "";
  height: 1px;
  width: 80px;
  background: var(--amber);
}

.header-rule .ornament {
  color: var(--amber);
  font-size: 14px;
}

.header-meta {
  margin-top: 28px;
  display: flex;
  justify-content: center;
  gap: 32px;
  font-size: 13px;
  color: var(--ink-mute);
  flex-wrap: wrap;
}

.header-meta span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.header-meta span::before {
  content: "◆";
  color: var(--amber);
  font-size: 8px;
}

main {
  padding: 64px 0;
}

main .container {
  background: #fff;
  box-shadow: var(--shadow-md);
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--line-soft);
}

.site-footer {
  background: var(--ink);
  color: rgba(255, 255, 255, 0.7);
  padding: 56px 0 32px;
  margin-top: 0;
  border-top: 4px solid var(--amber);
  position: relative;
  z-index: 1;
}

.site-footer .footer-notice {
  max-width: 720px;
  margin: 0 auto 40px;
  text-align: center;
  padding: 24px;
  border: 1px dashed rgba(192, 133, 82, 0.4);
  border-radius: var(--radius);
  background: rgba(192, 133, 82, 0.06);
}

.site-footer .footer-notice .notice-title {
  font-family: var(--font-serif);
  color: var(--amber-soft);
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 12px;
  letter-spacing: 0.05em;
}

.site-footer .footer-notice p {
  font-size: 13px;
  line-height: 1.9;
  color: rgba(255, 255, 255, 0.65);
  margin: 0;
}

.footer-links {
  text-align: center;
  margin-bottom: 32px;
}

.footer-links a {
  display: inline-block;
  color: var(--amber-soft);
  font-size: 15px;
  font-family: var(--font-serif);
  letter-spacing: 0.05em;
  padding: 8px 24px;
  border: 1px solid rgba(192, 133, 82, 0.4);
  border-radius: var(--radius);
  transition: all 0.25s ease;
}

.footer-links a:hover {
  background: var(--amber);
  color: #fff;
  border-color: var(--amber);
}

.footer-bottom {
  text-align: center;
  font-size: 12px;
  color: rgba(255, 255, 255, 0.4);
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  letter-spacing: 0.03em;
}

.text-serif {
  font-family: var(--font-serif);
}

.text-amber {
  color: var(--amber-deep);
}

.text-teal {
  color: var(--teal);
}

.back-to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  width: 48px;
  height: 48px;
  background: var(--teal);
  color: #fff;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: all 0.3s ease;
  z-index: 200;
}

.back-to-top:hover {
  background: var(--teal-deep);
  transform: translateY(0) scale(1.05);
}

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

.back-to-top svg {
  width: 20px;
  height: 20px;
}

@media (max-width: 768px) {
  .back-to-top {
    right: 16px;
    bottom: 16px;
    width: 44px;
    height: 44px;
  }

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

@media (max-width: 768px) {
  html {
    font-size: 15px;
  }

  .container {
    padding: 0 20px;
  }

  .page-header {
    padding: 40px 0 32px;
  }

  .page-header h1 {
    font-size: 28px;
  }

  .page-header .subtitle {
    font-size: 14px;
  }

  .header-rule::before,
  .header-rule::after {
    width: 40px;
  }

  .header-meta {
    gap: 16px;
    font-size: 12px;
  }

  main {
    padding: 32px 0;
  }

  main .container {
    border-radius: 0;
  }

  .nav-brand {
    font-size: 15px;
  }

  .nav-brand .brand-mark {
    width: 24px;
    height: 24px;
    line-height: 24px;
    font-size: 14px;
  }
}