@import url('https://fonts.googleapis.com/css2?family=Atkinson+Hyperlegible:wght@400;700&family=Crimson+Pro:wght@400;500;600;700&display=swap');

/* =========================================
   基础重置 & 根变量
   ========================================= */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --c-black: #000000;
  --c-white: #ffffff;
  --c-ink: #000000;
  --c-gray-90: #1a1a1a;
  --c-gray-70: #4d4d4d;
  --c-gray-40: #999999;
  --c-gray-15: #d9d9d9;
  --c-gray-05: #f2f2f2;

  --font-serif: 'Crimson Pro', 'Georgia', 'Songti SC', serif;
  --font-sans: 'Atkinson Hyperlegible', 'Helvetica Neue', 'Arial', 'PingFang SC', 'Microsoft YaHei', sans-serif;

  --max-w: 1200px;
  --nav-h: 64px;
  --radius-card: 28px;
  --radius-sm: 8px;

  --transition-fast: 200ms ease;
  --transition-std: 250ms ease;
}

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

body {
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.65;
  color: var(--c-black);
  background: var(--c-white);
  overflow-x: hidden;
}

/* sections 留出底部固定导航高度 */
article[id] {
  scroll-margin-top: calc(var(--nav-h) + 1rem);
}

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

a {
  color: inherit;
  text-decoration: none;
}

ul, ol {
  list-style: none;
}

hr {
  border: none;
  border-top: 2px solid var(--c-black);
  margin: 1rem 0 1.5rem;
}

/* =========================================
   全局容器
   ========================================= */
.site-wrapper {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* =========================================
   顶部固定导航（底部固定条）
   — 规格：底部固定，品牌缩为图标，分组导航
   ========================================= */
.site-header {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: var(--c-black);
  color: var(--c-white);
  height: var(--nav-h);
  border-top: 1px solid var(--c-gray-70);
}

.header-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  height: 100%;
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: center;
  gap: 1.5rem;
  padding: 0 1.5rem;
}

.header-brand {
  flex-shrink: 0;
}

.brand-logo,
.brand-text {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  background: var(--c-white);
  color: var(--c-black);
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 1.25rem;
  border-radius: var(--radius-sm);
  transition: opacity var(--transition-fast);
  text-decoration: none;
}

.brand-logo:hover,
.brand-text:hover {
  opacity: 0.8;
}

.logo-img {
  width: 28px;
  height: 28px;
  object-fit: contain;
}

/* 导航：header > nav > p > a */
.site-nav {
  overflow: hidden;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
  padding-bottom: 2px;
}

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

.nav-links a {
  display: inline-flex;
  align-items: center;
  padding: 0.5rem 0.75rem;
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 400;
  color: var(--c-white);
  white-space: nowrap;
  border-radius: var(--radius-sm);
  min-height: 40px;
  transition: background var(--transition-fast), color var(--transition-fast);
  letter-spacing: 0.03em;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  background: var(--c-white);
  color: var(--c-black);
  outline: none;
}

.nav-links a:focus-visible {
  outline: 2px solid var(--c-white);
  outline-offset: 2px;
}

/* =========================================
   主内容区（为底部导航留底部空间）
   ========================================= */
.site-main {
  flex: 1;
  padding-bottom: calc(var(--nav-h) + 2rem);
}

.wrap {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* =========================================
   Hero 区块
   规格：纯文字超大标题，右对齐，约70vh，网格底纹
   ========================================= */
.hero-section {
  min-height: 70vh;
  display: flex;
  align-items: flex-end;
  padding: 4rem 0 3rem;
  position: relative;
}

.hero-article {
  width: 100%;
  position: relative;
}

/* 网格底纹 */
.hero-grid-bg {
  position: absolute;
  inset: -2rem -1.5rem;
  background-image:
    linear-gradient(to right, var(--c-gray-15) 1px, transparent 1px),
    linear-gradient(to bottom, var(--c-gray-15) 1px, transparent 1px);
  background-size: 48px 48px;
  pointer-events: none;
  z-index: 0;
  mask-image: radial-gradient(ellipse 80% 80% at 80% 50%, black 40%, transparent 100%);
  -webkit-mask-image: radial-gradient(ellipse 80% 80% at 80% 50%, black 40%, transparent 100%);
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: right;
  max-width: 900px;
  margin-left: auto;
}

.eyebrow {
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--c-gray-70);
  margin-bottom: 1rem;
}

.hero-title {
  font-family: var(--font-serif);
  font-size: clamp(3rem, 10vw, 8rem);
  font-weight: 700;
  line-height: 1.05;
  letter-spacing: -0.02em;
  color: var(--c-black);
  margin-bottom: 1.5rem;
}

.hero-desc {
  font-family: var(--font-sans);
  font-size: clamp(1rem, 2vw, 1.25rem);
  line-height: 1.6;
  color: var(--c-gray-70);
  max-width: 560px;
  margin-left: auto;
}

/* =========================================
   正文 + 侧边栏布局
   ========================================= */
.content-section {
  padding: 3rem 0;
}

.content-article {
  width: 100%;
}

.content-with-aside {
  display: grid;
  grid-template-columns: 1fr 260px;
  gap: 3rem;
  align-items: start;
}

/* =========================================
   侧边栏（aside 在内容右侧）
   ========================================= */
.content-aside {
  position: sticky;
  top: 1.5rem;
  background: var(--c-gray-05);
  border-radius: var(--radius-card);
  border-bottom: 4px solid var(--c-black);
  padding: 1.75rem 1.5rem;
}

.aside-title {
  font-family: var(--font-serif);
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.aside-nav {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.aside-nav li a {
  display: block;
  padding: 0.4rem 0.5rem;
  font-size: 0.875rem;
  color: var(--c-gray-70);
  border-radius: var(--radius-sm);
  transition: background var(--transition-fast), color var(--transition-fast);
  min-height: 40px;
  display: flex;
  align-items: center;
}

.aside-nav li a:hover,
.aside-nav li a:focus-visible {
  background: var(--c-black);
  color: var(--c-white);
  outline: none;
}

/* =========================================
   正文内容（page.content 注入区域）
   ========================================= */
.content-main {
  min-width: 0;
}

/* page.content 内部样式 */
.content-main h2 {
  font-family: var(--font-serif);
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 700;
  line-height: 1.2;
  margin-top: 3rem;
  margin-bottom: 0.5rem;
  letter-spacing: -0.01em;
}

.content-main h2:first-child {
  margin-top: 0;
}

.content-main h3 {
  font-family: var(--font-serif);
  font-size: clamp(1.25rem, 3vw, 1.75rem);
  font-weight: 600;
  line-height: 1.3;
  margin-top: 2rem;
  margin-bottom: 0.5rem;
}

/* h2/h3 后紧跟 hr（结构抽签要求） */
.content-main h2 + hr,
.content-main h3 + hr {
  margin-top: 0;
  margin-bottom: 1.25rem;
}

.content-main p {
  font-size: 1rem;
  line-height: 1.75;
  color: var(--c-gray-90);
  margin-bottom: 1rem;
}

.content-main ul,
.content-main ol {
  list-style: none;
  margin-bottom: 1.25rem;
  padding-left: 0;
}

.content-main ul li,
.content-main ol li {
  padding: 0.35rem 0 0.35rem 1.25rem;
  position: relative;
  font-size: 1rem;
  line-height: 1.65;
  color: var(--c-gray-90);
}

.content-main ul li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.75rem;
  width: 8px;
  height: 2px;
  background: var(--c-black);
}

.content-main ol {
  counter-reset: ol-counter;
}

.content-main ol li {
  counter-increment: ol-counter;
}

.content-main ol li::before {
  content: counter(ol-counter, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 0.35rem;
  font-size: 0.75rem;
  font-weight: 700;
  font-family: var(--font-sans);
  color: var(--c-gray-40);
  letter-spacing: 0.05em;
}

.content-main strong {
  font-weight: 700;
  color: var(--c-black);
}

.content-main em {
  font-style: italic;
  font-family: var(--font-serif);
}

.content-main a {
  color: var(--c-black);
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: opacity var(--transition-fast);
}

.content-main a:hover {
  opacity: 0.6;
}

/* article 区块（page.content 里的7个 article） */
.content-main article {
  padding: 2.5rem 0;
  border-top: 1px solid var(--c-gray-15);
}

.content-main article:first-child {
  border-top: none;
  padding-top: 0;
}

/* 卡片样式（正文内如有） */
.content-main .card,
.content-main [class*="card"] {
  border-radius: var(--radius-card);
  border-bottom: 4px solid var(--c-black);
  background: var(--c-gray-05);
  padding: 1.75rem;
  margin-bottom: 1.25rem;
}

/* 问答/FAQ */
.content-main details {
  border-top: 1px solid var(--c-gray-15);
  padding: 1rem 0;
}

.content-main details summary {
  font-weight: 700;
  cursor: pointer;
  font-family: var(--font-serif);
  font-size: 1.1rem;
}

/* 表格 */
.content-main table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1.5rem;
  font-size: 0.9375rem;
}

.content-main th,
.content-main td {
  padding: 0.75rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--c-gray-15);
}

.content-main th {
  font-weight: 700;
  font-family: var(--font-serif);
  border-bottom: 2px solid var(--c-black);
}

/* blockquote */
.content-main blockquote {
  border-left: 4px solid var(--c-black);
  padding-left: 1.25rem;
  margin: 1.5rem 0;
  font-family: var(--font-serif);
  font-size: 1.125rem;
  font-style: italic;
  color: var(--c-gray-70);
}

/* code/pre */
.content-main code {
  font-family: 'Courier New', monospace;
  font-size: 0.875em;
  background: var(--c-gray-05);
  padding: 0.15em 0.4em;
  border-radius: 4px;
}

.content-main pre {
  background: var(--c-gray-05);
  padding: 1.25rem;
  border-radius: var(--radius-sm);
  overflow-x: auto;
  margin-bottom: 1.25rem;
  border-left: 4px solid var(--c-black);
}

.content-main pre code {
  background: none;
  padding: 0;
}

/* =========================================
   页脚
   规格：单行极简，超大品牌字，版权居中
   结构：footer > address + ul
   ========================================= */
.site-footer {
  background: var(--c-black);
  color: var(--c-white);
  padding: 3rem 1.5rem calc(var(--nav-h) + 3rem);
}

.footer-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.5rem;
}

.footer-brand-name {
  font-family: var(--font-serif);
  font-size: clamp(3rem, 10vw, 7rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--c-white);
  line-height: 1;
  display: block;
  text-align: center;
}

.footer-address {
  font-style: normal;
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.5rem;
  justify-content: center;
  font-size: 0.875rem;
  color: var(--c-gray-40);
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 0.5rem;
  justify-content: center;
}

.footer-links li a {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.75rem;
  font-size: 0.8125rem;
  color: var(--c-gray-40);
  border: 1px solid var(--c-gray-70);
  border-radius: var(--radius-sm);
  min-height: 40px;
  transition: color var(--transition-fast), border-color var(--transition-fast);
}

.footer-links li a:hover {
  color: var(--c-white);
  border-color: var(--c-white);
}

.footer-copy {
  font-size: 0.8125rem;
  color: var(--c-gray-40);
  text-align: center;
  line-height: 1.5;
}

/* =========================================
   动效：Stagger List + Parallax Scroll
   ========================================= */
@media (prefers-reduced-motion: no-preference) {
  .content-main article {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 400ms ease, transform 400ms ease;
  }

  .content-main article.is-visible {
    opacity: 1;
    transform: translateY(0);
  }

  .aside-nav li {
    opacity: 0;
    transform: translateX(12px);
    transition: opacity 300ms ease, transform 300ms ease;
  }

  .aside-nav li.is-visible {
    opacity: 1;
    transform: translateX(0);
  }

  .hero-content {
    animation: heroEntrance 600ms ease both;
    animation-delay: 100ms;
  }

  @keyframes heroEntrance {
    from {
      opacity: 0;
      transform: translateY(32px);
    }
    to {
      opacity: 1;
      transform: translateY(0);
    }
  }

  .nav-links a {
    transition: background var(--transition-fast), color var(--transition-fast);
  }
}

/* =========================================
   响应式断点
   ========================================= */
@media (max-width: 900px) {
  .content-with-aside {
    grid-template-columns: 1fr;
  }

  .content-aside {
    position: static;
    order: -1;
  }

  .aside-nav {
    flex-direction: row;
    flex-wrap: wrap;
  }

  .aside-nav li a {
    font-size: 0.8125rem;
    padding: 0.3rem 0.6rem;
  }
}

@media (max-width: 600px) {
  :root {
    --nav-h: 56px;
  }

  .hero-section {
    min-height: 70vh;
    padding: 2rem 0 2rem;
  }

  .hero-title {
    font-size: clamp(2.5rem, 14vw, 5rem);
  }

  .header-inner {
    padding: 0 1rem;
    gap: 0.75rem;
  }

  .nav-links a {
    font-size: 0.75rem;
    padding: 0.4rem 0.5rem;
  }

  .wrap {
    padding: 0 1rem;
  }

  .content-main h2 {
    font-size: 1.5rem;
  }

  .content-main h3 {
    font-size: 1.2rem;
  }

  .footer-address {
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
  }

  .site-footer {
    padding: 2.5rem 1rem calc(var(--nav-h) + 2.5rem);
  }
}

@media (max-width: 375px) {
  .hero-title {
    font-size: 2.25rem;
  }

  .nav-links {
    gap: 0.1rem;
  }

  .nav-links a {
    padding: 0.35rem 0.4rem;
    font-size: 0.7rem;
  }
}

/* =========================================
   无横向滚动保障
   ========================================= */
html, body {
  max-width: 100%;
  overflow-x: hidden;
}

/* =========================================
   焦点可见性（可访问性）
   ========================================= */
:focus-visible {
  outline: 2px solid var(--c-black);
  outline-offset: 3px;
}

.site-footer :focus-visible {
  outline-color: var(--c-white);
}

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