@import url('https://fonts.googleapis.com/css2?family=Fredoka:wght@400;500;600;700&family=Nunito:wght@300;400;500;600;700&display=swap');

/* ===== CSS 变量 ===== */
:root {
  --mint: #b4fde1;
  --fog-blue: #add8e6;
  --ink: #172620;
  --ink-light: #2a3d36;
  --ink-mid: #3d5a4e;
  --mint-dark: #7de8bf;
  --mint-pale: #e0fff4;
  --blue-pale: #dff2fa;
  --white: #ffffff;
  --text-main: #172620;
  --text-muted: #4a6b5e;
  --text-light: #7a9e90;
  --border-radius-lg: 24px;
  --border-radius-md: 16px;
  --border-radius-sm: 12px;
  --border-radius-xs: 8px;
  --border-width: 3px;
  --shadow-clay: 4px 4px 12px rgba(23,38,32,0.18), inset -2px -2px 8px rgba(23,38,32,0.10);
  --shadow-clay-hover: 6px 6px 18px rgba(23,38,32,0.22), inset -2px -2px 8px rgba(23,38,32,0.10);
  --shadow-float: 0 8px 32px rgba(23,38,32,0.15);
  --font-head: 'Fredoka', 'Nunito', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-body: 'Nunito', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --nav-h: 64px;
  --transition-std: 200ms ease-out;
  --transition-bounce: cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* ===== 重置 ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-h) + 12px);
  font-size: 16px;
}
body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--text-main);
  background: var(--ink);
  overflow-x: hidden;
}
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
ul, menu { list-style: none; }
button, input, select, textarea { font-family: inherit; font-size: inherit; }

/* ===== 页面容器 ===== */
.page-wrapper { min-height: 100vh; display: flex; flex-direction: column; }

/* ===== 顶部导航 ===== */
.site-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  height: var(--nav-h);
  background: var(--ink);
  border-bottom: var(--border-width) solid var(--ink-light);
  box-shadow: 0 2px 16px rgba(23,38,32,0.4);
}
.header-inner {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 20px;
  height: 100%;
  display: flex;
  align-items: center;
  gap: 16px;
}
.brand-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border-radius: var(--border-radius-sm);
  border: var(--border-width) solid var(--mint);
  background: var(--ink-light);
  box-shadow: var(--shadow-clay);
  flex-shrink: 0;
  transition: transform var(--transition-std), box-shadow var(--transition-std);
}
.brand-icon:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-clay-hover);
}
.logo-mark { width: 32px; height: 32px; object-fit: contain; border-radius: 6px; }
.logo-text-mark {
  font-family: var(--font-head);
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--mint);
  line-height: 1;
}

/* 搜索 */
.header-search { flex: 1; max-width: 380px; margin-left: auto; }
.search-form {
  display: flex;
  align-items: center;
  background: var(--ink-light);
  border: var(--border-width) solid var(--mint-dark);
  border-radius: var(--border-radius-sm);
  overflow: hidden;
  box-shadow: inset -1px -1px 6px rgba(23,38,32,0.3);
  transition: border-color var(--transition-std), box-shadow var(--transition-std);
}
.search-form:focus-within {
  border-color: var(--mint);
  box-shadow: inset -1px -1px 6px rgba(23,38,32,0.3), 0 0 0 3px rgba(180,253,225,0.2);
}
.search-input {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  padding: 10px 14px;
  color: var(--mint-pale);
  font-size: 0.9rem;
}
.search-input::placeholder { color: var(--text-light); }
.search-btn {
  background: transparent;
  border: none;
  padding: 10px 14px;
  color: var(--mint);
  cursor: pointer;
  display: flex;
  align-items: center;
  min-height: 40px;
  transition: color var(--transition-std);
}
.search-btn:hover { color: var(--mint-dark); }

/* 汉堡 / 全屏菜单 */
.nav-details { position: static; }
.nav-details summary { list-style: none; }
.nav-details summary::-webkit-details-marker { display: none; }

.hamburger-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: var(--border-radius-sm);
  border: var(--border-width) solid var(--fog-blue);
  background: var(--ink-light);
  box-shadow: var(--shadow-clay);
  cursor: pointer;
  flex-shrink: 0;
  transition: background var(--transition-std), transform var(--transition-std);
}
.hamburger-btn:hover { background: var(--ink-mid); transform: scale(1.05); }
.ham-icon {
  display: flex;
  flex-direction: column;
  gap: 5px;
  width: 22px;
}
.ham-icon span {
  display: block;
  height: 3px;
  border-radius: 2px;
  background: var(--fog-blue);
  transition: transform var(--transition-std), opacity var(--transition-std);
}
.nav-details[open] .ham-icon span:nth-child(1) { transform: translateY(8px) rotate(45deg); }
.nav-details[open] .ham-icon span:nth-child(2) { opacity: 0; }
.nav-details[open] .ham-icon span:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }

.nav-overlay {
  position: fixed;
  inset: 0;
  z-index: 999;
  background: rgba(23,38,32,0.97);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  animation: overlayFadeIn 250ms ease-out;
}
@keyframes overlayFadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}
.nav-overlay-inner {
  width: 100%;
  max-width: 500px;
  padding: 48px 32px;
}
.nav-overlay-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 40px;
}
.nav-brand-name {
  font-family: var(--font-head);
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--mint);
  letter-spacing: 0.02em;
}
.nav-close-btn {
  background: var(--ink-light);
  border: var(--border-width) solid var(--mint-dark);
  border-radius: var(--border-radius-xs);
  color: var(--mint);
  width: 44px;
  height: 44px;
  font-size: 1.2rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-clay);
  transition: background var(--transition-std), transform var(--transition-std);
}
.nav-close-btn:hover { background: var(--ink-mid); transform: scale(1.08); }

.nav-menu { display: flex; flex-direction: column; gap: 8px; }
.nav-link {
  display: block;
  padding: 14px 20px;
  font-family: var(--font-head);
  font-size: 1.15rem;
  font-weight: 500;
  color: var(--mint-pale);
  border-radius: var(--border-radius-md);
  border: 2px solid transparent;
  transition: background var(--transition-std), border-color var(--transition-std), color var(--transition-std), transform 180ms var(--transition-bounce);
  min-height: 48px;
  display: flex;
  align-items: center;
}
.nav-link:hover {
  background: rgba(180,253,225,0.1);
  border-color: var(--mint);
  color: var(--mint);
  transform: translateX(6px);
}

/* ===== Hero ===== */
.hero-section {
  position: relative;
  width: 100%;
  min-height: 70vh;
  display: flex;
  align-items: center;
  margin-top: var(--nav-h);
  overflow: hidden;
}
.hero-media {
  position: absolute;
  inset: 0;
  z-index: 0;
}
.hero-bg-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}
.hero-mask {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    rgba(23,38,32,0.85) 0%,
    rgba(23,38,32,0.6) 50%,
    rgba(23,38,32,0.4) 100%
  );
}
.hero-content {
  position: relative;
  z-index: 1;
  max-width: 1280px;
  margin: 0 auto;
  padding: 60px 32px;
  width: 100%;
  text-align: left;
}
.hero-h1 {
  font-family: var(--font-head);
  font-size: clamp(1.8rem, 5vw, 3.2rem);
  font-weight: 700;
  color: var(--mint);
  line-height: 1.25;
  margin-bottom: 18px;
  text-shadow: 2px 2px 12px rgba(23,38,32,0.5);
  letter-spacing: 0.01em;
}
.hero-desc {
  font-size: clamp(1rem, 2vw, 1.15rem);
  color: var(--mint-pale);
  max-width: 560px;
  margin-bottom: 32px;
  line-height: 1.7;
}
.clay-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  background: linear-gradient(135deg, var(--mint) 0%, var(--mint-dark) 100%);
  color: var(--ink);
  font-family: var(--font-head);
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--border-radius-md);
  border: var(--border-width) solid var(--mint-dark);
  box-shadow: 4px 4px 12px rgba(23,38,32,0.3), inset -2px -2px 8px rgba(23,38,32,0.15);
  cursor: pointer;
  transition: transform 200ms var(--transition-bounce), box-shadow var(--transition-std), background var(--transition-std);
  min-height: 48px;
  text-decoration: none;
}
.clay-btn:hover {
  transform: translateY(-3px) scale(1.03);
  box-shadow: 6px 8px 20px rgba(23,38,32,0.35), inset -2px -2px 8px rgba(23,38,32,0.15);
  background: linear-gradient(135deg, var(--mint-dark) 0%, var(--mint) 100%);
}
.clay-btn:active {
  transform: translateY(1px) scale(0.98);
  box-shadow: 2px 2px 8px rgba(23,38,32,0.25), inset -1px -1px 6px rgba(23,38,32,0.15);
}
.hero-cta { font-size: 1.05rem; padding: 16px 40px; }

/* ===== 内容布局 ===== */
.content-layout {
  flex: 1;
  background: var(--mint-pale);
  max-width: 1280px;
  margin: 0 auto;
  width: 100%;
  padding: 40px 24px;
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 32px;
  align-items: start;
}

/* ===== aside ===== */
.content-aside {
  position: sticky;
  top: calc(var(--nav-h) + 20px);
  display: flex;
  flex-direction: column;
  gap: 20px;
}
.clay-card {
  background: linear-gradient(135deg, var(--mint-pale) 0%, var(--blue-pale) 100%);
  border: var(--border-width) solid var(--mint-dark);
  border-radius: var(--border-radius-lg);
  padding: 24px 20px;
  box-shadow: var(--shadow-clay);
  transition: transform var(--transition-std), box-shadow var(--transition-std);
}
.clay-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-clay-hover);
}
.aside-brand-card {
  background: linear-gradient(135deg, var(--blue-pale) 0%, var(--mint-pale) 100%);
  border-color: var(--fog-blue);
}
.aside-title {
  font-family: var(--font-head);
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 16px;
}
.aside-subtitle {
  font-family: var(--font-head);
  font-size: 1rem;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 10px;
}
.aside-nav-list { display: flex; flex-direction: column; gap: 4px; }
.aside-nav-link {
  display: block;
  padding: 9px 12px;
  border-radius: var(--border-radius-xs);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-main);
  border: 2px solid transparent;
  min-height: 40px;
  display: flex;
  align-items: center;
  transition: background var(--transition-std), border-color var(--transition-std), transform 180ms var(--transition-bounce);
}
.aside-nav-link:hover {
  background: rgba(180,253,225,0.5);
  border-color: var(--mint-dark);
  transform: translateX(4px);
}
.aside-brand-desc {
  font-size: 0.875rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ===== 眉题 ===== */
.eyebrow-label {
  display: inline-block;
  font-family: var(--font-head);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--ink-mid);
  background: linear-gradient(90deg, var(--mint) 0%, var(--fog-blue) 100%);
  padding: 3px 10px;
  border-radius: 20px;
  margin-bottom: 8px;
  border: 1px solid var(--mint-dark);
}
.eyebrow-light {
  color: var(--ink);
  background: linear-gradient(90deg, rgba(180,253,225,0.3) 0%, rgba(173,216,230,0.3) 100%);
  border-color: var(--mint-dark);
}

/* ===== 主文章 ===== */
.content-main { min-width: 0; }
.main-article {
  background: var(--white);
  border: var(--border-width) solid var(--mint-dark);
  border-radius: var(--border-radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-clay);
}
.article-body-section { padding: 40px 36px; }

/* 正文排版 */
.article-body-section h1,
.article-body-section h2,
.article-body-section h3,
.article-body-section h4 {
  font-family: var(--font-head);
  color: var(--ink);
  line-height: 1.3;
  margin-top: 2em;
  margin-bottom: 0.6em;
}
.article-body-section h1 { font-size: 2rem; font-weight: 700; margin-top: 0; }
.article-body-section h2 {
  font-size: 1.5rem;
  font-weight: 600;
  padding-bottom: 10px;
  border-bottom: 3px solid var(--mint);
  position: relative;
}
.article-body-section h2::before {
  content: '';
  display: inline-block;
  width: 8px;
  height: 8px;
  background: var(--mint-dark);
  border-radius: 50%;
  margin-right: 10px;
  vertical-align: middle;
  margin-bottom: 2px;
}
.article-body-section h3 { font-size: 1.2rem; font-weight: 600; color: var(--ink-mid); }
.article-body-section p {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text-main);
  margin-bottom: 1.2em;
}
.article-body-section ul,
.article-body-section ol {
  padding-left: 1.5em;
  margin-bottom: 1.2em;
}
.article-body-section li {
  font-size: 1rem;
  line-height: 1.7;
  margin-bottom: 0.4em;
  color: var(--text-main);
}
.article-body-section a {
  color: var(--ink-mid);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: color var(--transition-std);
}
.article-body-section a:hover { color: var(--ink); }
.article-body-section strong { font-weight: 700; color: var(--ink); }
.article-body-section em { color: var(--ink-mid); font-style: italic; }
.article-body-section blockquote {
  border-left: 4px solid var(--mint-dark);
  background: var(--mint-pale);
  border-radius: 0 var(--border-radius-sm) var(--border-radius-sm) 0;
  padding: 16px 20px;
  margin: 1.5em 0;
  color: var(--text-muted);
  font-style: italic;
}
.article-body-section table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5em 0;
  border-radius: var(--border-radius-sm);
  overflow: hidden;
  border: 2px solid var(--mint-dark);
}
.article-body-section th {
  background: var(--ink);
  color: var(--mint);
  font-family: var(--font-head);
  font-weight: 600;
  padding: 12px 16px;
  text-align: left;
}
.article-body-section td {
  padding: 10px 16px;
  border-bottom: 1px solid var(--mint-pale);
  font-size: 0.95rem;
}
.article-body-section tr:nth-child(even) td { background: var(--mint-pale); }
.article-body-section img {
  border-radius: var(--border-radius-md);
  border: var(--border-width) solid var(--mint-dark);
  box-shadow: var(--shadow-float);
  margin: 1.5em 0;
}

/* section 内分区 */
.article-body-section section {
  padding-top: 32px;
  margin-top: 32px;
  border-top: 2px dashed var(--mint-dark);
  scroll-margin-top: calc(var(--nav-h) + 16px);
}
.article-body-section section:first-child {
  padding-top: 0;
  margin-top: 0;
  border-top: none;
}

/* ===== 页脚联系块 ===== */
.footer-contact-block {
  background: linear-gradient(135deg, var(--ink-light) 0%, var(--ink-mid) 100%);
  border-top: var(--border-width) solid var(--mint-dark);
  border-bottom: var(--border-width) solid var(--mint-dark);
  padding: 56px 24px;
}
.footer-contact-inner {
  max-width: 640px;
  margin: 0 auto;
  text-align: center;
}
.footer-contact-title {
  font-family: var(--font-head);
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--mint);
  margin-bottom: 24px;
}
.subscribe-form {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: 16px;
}
.subscribe-input {
  flex: 1;
  min-width: 220px;
  padding: 14px 18px;
  background: var(--ink);
  border: var(--border-width) solid var(--mint-dark);
  border-radius: var(--border-radius-md);
  color: var(--mint-pale);
  font-size: 1rem;
  outline: none;
  box-shadow: inset -1px -1px 6px rgba(23,38,32,0.4);
  min-height: 48px;
  transition: border-color var(--transition-std);
}
.subscribe-input::placeholder { color: var(--text-light); }
.subscribe-input:focus { border-color: var(--mint); }
.subscribe-btn {
  background: linear-gradient(135deg, var(--fog-blue) 0%, var(--mint) 100%);
  border-color: var(--mint-dark);
  padding: 14px 28px;
}
.footer-email {
  font-size: 0.9rem;
  color: var(--text-light);
  margin-top: 12px;
}
.footer-email a { color: var(--mint); text-decoration: underline; text-underline-offset: 2px; }

/* 页脚主行 */
.footer-main-row {
  background: var(--ink);
  max-width: 1280px;
  margin: 0 auto;
  padding: 48px 32px 32px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}
.footer-brand-col {}
.footer-logo-link { display: inline-block; margin-bottom: 16px; }
.footer-logo { height: 40px; width: auto; }
.footer-logo-text {
  font-family: var(--font-head);
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--mint);
}
.footer-brand-desc {
  font-size: 0.9rem;
  color: var(--text-light);
  line-height: 1.6;
  max-width: 320px;
}
.footer-nav-list { display: flex; flex-direction: column; gap: 8px; }
.footer-nav-link {
  font-size: 0.9rem;
  color: var(--text-light);
  min-height: 40px;
  display: flex;
  align-items: center;
  padding: 4px 0;
  transition: color var(--transition-std), transform 180ms var(--transition-bounce);
}
.footer-nav-link:hover { color: var(--mint); transform: translateX(4px); }

/* 底栏 */
.footer-bottom-bar {
  background: var(--ink);
  border-top: 1px solid var(--ink-light);
}
.footer-bottom-nav {
  max-width: 1280px;
  margin: 0 auto;
  padding: 16px 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.footer-copyright {
  font-size: 0.85rem;
  color: var(--text-light);
}
.footer-legal-links { display: flex; gap: 16px; }
.footer-legal-link {
  font-size: 0.85rem;
  color: var(--text-light);
  min-height: 40px;
  display: flex;
  align-items: center;
  transition: color var(--transition-std);
}
.footer-legal-link:hover { color: var(--mint); }

/* ===== Scroll Reveal 动效 ===== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 600ms ease-out, transform 600ms var(--transition-bounce);
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}
.reveal-left {
  opacity: 0;
  transform: translateX(-24px);
  transition: opacity 600ms ease-out, transform 600ms var(--transition-bounce);
}
.reveal-left.visible {
  opacity: 1;
  transform: translateX(0);
}

@media (prefers-reduced-motion: reduce) {
  .reveal, .reveal-left {
    opacity: 1;
    transform: none;
    transition: none;
  }
  html { scroll-behavior: auto; }
  .clay-btn { transition: none; }
  .nav-link, .aside-nav-link, .footer-nav-link { transition: none; }
  .nav-overlay { animation: none; }
}

/* ===== 并行滚动视差 ===== */
@media (prefers-reduced-motion: no-preference) {
  .hero-bg-img {
    will-change: transform;
    transform: scale(1.08);
  }
}

/* ===== 响应式 ===== */
@media (max-width: 900px) {
  .content-layout {
    grid-template-columns: 1fr;
    padding: 24px 16px;
  }
  .content-aside {
    position: static;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
  }
  .footer-main-row {
    grid-template-columns: 1fr;
    padding: 32px 20px;
    gap: 24px;
  }
}

@media (max-width: 600px) {
  :root { --nav-h: 56px; }
  .header-inner { padding: 0 12px; gap: 10px; }
  .header-search { max-width: 160px; }
  .search-input { padding: 8px 10px; font-size: 0.85rem; }
  .search-btn { padding: 8px 10px; }
  .hero-content { padding: 40px 20px; }
  .hero-h1 { font-size: 1.5rem; }
  .hero-desc { font-size: 0.95rem; }
  .hero-cta { padding: 13px 24px; font-size: 0.95rem; }
  .content-layout { padding: 16px 12px; gap: 16px; }
  .content-aside { grid-template-columns: 1fr; }
  .article-body-section { padding: 24px 16px; }
  .article-body-section h1 { font-size: 1.4rem; }
  .article-body-section h2 { font-size: 1.2rem; }
  .footer-contact-block { padding: 36px 16px; }
  .footer-contact-title { font-size: 1.4rem; }
  .subscribe-form { flex-direction: column; }
  .subscribe-input { min-width: 0; }
  .footer-bottom-nav { flex-direction: column; text-align: center; }
  .nav-overlay-inner { padding: 32px 20px; }
  .nav-link { font-size: 1rem; }
}

@media (max-width: 375px) {
  .hero-section { min-height: 60vh; }
  .article-body-section { padding: 20px 14px; }
}

button[aria-expanded]{min-width:44px;min-height:44px}