@import url('https://fonts.googleapis.com/css2?family=Space+Mono:wght@400;700&family=Syncopate:wght@400;700&display=swap');

/* ===== CSS 变量 ===== */
:root {
  --clr-bg: #ffffff;
  --clr-fg: #000000;
  --clr-border: #000000;
  --clr-muted: #444444;
  --clr-subtle: #f0f0f0;
  --font-heading: 'Syncopate', sans-serif;
  --font-body: 'Space Mono', monospace;
  --max-w: 1200px;
  --header-h: 60px;
  --gap: 2rem;
  --transition: 220ms ease;
}

/* ===== 重置 ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.7;
  background: var(--clr-bg);
  color: var(--clr-fg);
  overflow-x: hidden;
}
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(--clr-fg); margin: 0.75rem 0 1.25rem; }

/* ===== 全局包装 ===== */
.page-wrap { min-height: 100vh; display: flex; flex-direction: column; }

/* ===== 顶部 Header（固定底条风格，放顶部） ===== */
.site-header {
  position: fixed;
  bottom: 0; left: 0; right: 0;
  z-index: 100;
  background: var(--clr-fg);
  color: var(--clr-bg);
  border-top: 2px solid var(--clr-border);
  height: var(--header-h);
}
.header-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  height: 100%;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1rem;
  letter-spacing: 0.15em;
  color: var(--clr-bg);
  text-transform: uppercase;
  min-height: 40px;
  display: flex;
  align-items: center;
}
.header-right {
  display: flex;
  align-items: center;
  gap: 1rem;
}
.cta-btn {
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  background: var(--clr-bg);
  color: var(--clr-fg);
  border: 2px solid var(--clr-bg);
  padding: 0.55rem 1.1rem;
  min-height: 40px;
  display: flex;
  align-items: center;
  transition: background var(--transition), color var(--transition);
}
.cta-btn:hover { background: transparent; color: var(--clr-bg); }

/* ===== 汉堡按钮 ===== */
.hamburger {
  background: none;
  border: 2px solid var(--clr-bg);
  cursor: pointer;
  padding: 0.45rem 0.6rem;
  min-height: 40px;
  min-width: 40px;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  transition: border-color var(--transition);
}
.hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--clr-bg);
  transition: background var(--transition);
}
.hamburger:hover { border-color: #ccc; }

/* ===== 全屏遮罩菜单 ===== */
.overlay-menu {
  position: fixed;
  inset: 0;
  z-index: 200;
  background: var(--clr-fg);
  color: var(--clr-bg);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity 250ms ease;
}
.overlay-menu.is-open {
  opacity: 1;
  pointer-events: auto;
}
.menu-close {
  position: absolute;
  top: 1.5rem;
  right: 1.5rem;
  background: none;
  border: 2px solid var(--clr-bg);
  color: var(--clr-bg);
  font-size: 1.2rem;
  cursor: pointer;
  min-height: 44px;
  min-width: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--transition);
}
.menu-close:hover { background: rgba(255,255,255,0.1); }
.overlay-nav ol {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  text-align: center;
}
.overlay-nav ol li a {
  font-family: var(--font-heading);
  font-size: clamp(1rem, 3vw, 1.4rem);
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--clr-bg);
  display: block;
  padding: 0.6rem 1rem;
  border-bottom: 1px solid rgba(255,255,255,0.15);
  transition: color var(--transition);
}
.overlay-nav ol li a:hover { color: #aaa; }

/* ===== Hero ===== */
.hero {
  position: relative;
  min-height: 70vh;
  background: var(--clr-fg);
  color: var(--clr-bg);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  padding-bottom: var(--header-h);
}
.page-hero {
  position: relative;
  min-height: 38vh;
  background: var(--clr-fg);
  color: var(--clr-bg);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  padding-bottom: var(--header-h);
}
.page-hero--service { min-height: 32vh; }
.page-hero--cases { min-height: 32vh; }
.page-hero--faq { min-height: 32vh; }
.page-hero--about { min-height: 32vh; }
.page-hero--contact { min-height: 32vh; }
.page-hero--privacy { min-height: 32vh; }

/* 网格底纹 */
.hero-grid-bg {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.06) 1px, transparent 1px);
  background-size: 48px 48px;
  pointer-events: none;
}

/* 斜切底边 */
.hero-slash {
  position: absolute;
  bottom: calc(var(--header-h) - 2px);
  left: 0; right: 0;
  height: 60px;
  background: var(--clr-bg);
  clip-path: polygon(0 60px, 100% 0, 100% 60px);
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 3rem 1.5rem 5rem;
  max-width: 800px;
}
.hero-content--left { text-align: left; align-self: flex-start; margin-left: 5%; }
.hero-logo { max-height: 64px; width: auto; margin: 0 auto 1.5rem; }
.hero h1, .page-hero h1 {
  font-family: var(--font-heading);
  font-size: clamp(1.8rem, 5vw, 3.5rem);
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  line-height: 1.15;
  margin-bottom: 1rem;
}
.hero-sub {
  font-size: 1rem;
  color: rgba(255,255,255,0.75);
  max-width: 560px;
  margin: 0 auto 2rem;
  line-height: 1.7;
}
.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
}
.eyebrow {
  font-family: var(--font-heading);
  font-size: 0.7rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.55);
  margin-bottom: 0.75rem;
}
.page-date, .page-dates {
  font-size: 0.85rem;
  color: rgba(255,255,255,0.5);
  margin-top: 0.75rem;
}
.page-dates { display: flex; gap: 1.5rem; flex-wrap: wrap; }

/* ===== 按钮 ===== */
.btn-primary {
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  background: var(--clr-bg);
  color: var(--clr-fg);
  border: 2px solid var(--clr-bg);
  padding: 0.75rem 1.75rem;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  transition: background var(--transition), color var(--transition);
}
.btn-primary:hover { background: transparent; color: var(--clr-bg); }
.btn-secondary {
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  background: transparent;
  color: var(--clr-bg);
  border: 2px solid rgba(255,255,255,0.5);
  padding: 0.75rem 1.75rem;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  transition: border-color var(--transition), color var(--transition);
}
.btn-secondary:hover { border-color: var(--clr-bg); }

/* ===== 内容区主体 ===== */
.content-section {
  flex: 1;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 3rem 1.5rem calc(var(--header-h) + 3rem);
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: var(--gap);
  width: 100%;
}

/* ===== 侧边栏 (左侧) ===== */
.content-aside {
  border-right: 2px solid var(--clr-fg);
  padding-right: 1.5rem;
}
.content-aside h2 {
  font-family: var(--font-heading);
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  margin-bottom: 0.25rem;
}
.content-aside nav ol {
  display: flex;
  flex-direction: column;
  gap: 0;
}
.content-aside nav ol li a {
  display: block;
  padding: 0.5rem 0;
  font-size: 0.82rem;
  border-bottom: 1px solid #ddd;
  transition: color var(--transition);
  line-height: 1.4;
  min-height: 40px;
  display: flex;
  align-items: center;
}
.content-aside nav ol li a:hover { color: var(--clr-muted); }
.aside-list li a {
  display: flex;
  align-items: center;
  padding: 0.5rem 0;
  font-size: 0.82rem;
  border-bottom: 1px solid #ddd;
  min-height: 40px;
  transition: color var(--transition);
}
.aside-list li a:hover { color: var(--clr-muted); }

/* ===== 正文主容器 ===== */
.content-main {
  min-width: 0;
}
.hero-img { margin-bottom: 1.5rem; }
.hero-img-inner { width: 100%; max-height: 360px; object-fit: cover; border: 2px solid var(--clr-fg); }

.page-content {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--clr-fg);
}
.page-content h2 {
  font-family: var(--font-heading);
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin: 2rem 0 0.5rem;
}
.page-content h3 {
  font-family: var(--font-heading);
  font-size: 0.95rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin: 1.5rem 0 0.5rem;
}
.page-content h2 + hr,
.page-content h3 + hr { margin-bottom: 1rem; }
.page-content p { margin-bottom: 1rem; }
.page-content ul, .page-content ol {
  margin: 0 0 1rem 1.5rem;
  list-style: disc;
}
.page-content ol { list-style: decimal; }
.page-content li { margin-bottom: 0.4rem; }
.page-content strong { font-weight: 700; }
.page-content a {
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: color var(--transition);
}
.page-content a:hover { color: var(--clr-muted); }
.page-content table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1.5rem;
  font-size: 0.9rem;
}
.page-content th, .page-content td {
  border: 1px solid var(--clr-fg);
  padding: 0.5rem 0.75rem;
  text-align: left;
}
.page-content th { background: var(--clr-subtle); font-weight: 700; }

/* FAQ 专属 */
.faq-content h2 { border-left: 4px solid var(--clr-fg); padding-left: 0.75rem; }
/* Privacy 专属 */
.privacy-content { max-width: 720px; }

/* ===== 网格板块（首页） ===== */
.grid-section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 2rem 1.5rem 0;
  width: 100%;
}
.grid-section h2 {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  margin-bottom: 0.25rem;
}
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
  margin-bottom: 3rem;
}
.card {
  border: 2px solid var(--clr-fg);
  transition: background var(--transition), color var(--transition);
}
.card:hover { background: var(--clr-fg); color: var(--clr-bg); }
.card a {
  display: block;
  padding: 1.5rem;
  height: 100%;
}
.card h3 {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 0.25rem;
}
.card hr { margin: 0.5rem 0 0.75rem; }
.card p { font-size: 0.85rem; line-height: 1.6; margin-bottom: 0.75rem; }
.card-link {
  font-family: var(--font-heading);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  display: inline-block;
  border-bottom: 1px solid currentColor;
}

/* ===== Cases DL ===== */
.cases-dl { display: block; }
.cases-dl dt {
  margin-top: 0.75rem;
}
.cases-dl dt a {
  font-family: var(--font-heading);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  display: flex;
  align-items: center;
  min-height: 40px;
  border-bottom: 1px solid #ddd;
  transition: color var(--transition);
}
.cases-dl dt a:hover { color: var(--clr-muted); }
.cases-dl dd {
  font-size: 0.78rem;
  color: var(--clr-muted);
  line-height: 1.5;
  padding: 0.25rem 0 0.5rem;
}

/* ===== Contact Box ===== */
.contact-box {
  margin-top: 2.5rem;
  border: 2px solid var(--clr-fg);
  padding: 1.5rem;
}
.contact-box h2 {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: 0.25rem;
}
.contact-box p { margin: 0.75rem 0; font-size: 0.9rem; }

/* ===== Footer ===== */
.site-footer {
  background: var(--clr-fg);
  color: var(--clr-bg);
  margin-bottom: var(--header-h);
}
.footer-cta {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 2.5rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  flex-wrap: wrap;
  border-bottom: 1px solid rgba(255,255,255,0.2);
}
.footer-cta span {
  font-size: 0.9rem;
  line-height: 1.5;
  max-width: 540px;
  color: rgba(255,255,255,0.8);
}
.footer-bar {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 1.25rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}
.footer-bar address {
  font-style: normal;
  font-size: 0.78rem;
  color: rgba(255,255,255,0.5);
}
.footer-bar ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1rem;
}
.footer-bar ul li a {
  font-size: 0.75rem;
  color: rgba(255,255,255,0.55);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  transition: color var(--transition);
}
.footer-bar ul li a:hover { color: var(--clr-bg); }

/* ===== 动效：交错列表淡入 ===== */
@media (prefers-reduced-motion: no-preference) {
  .card {
    animation: fadeUp 400ms both;
  }
  .card:nth-child(1) { animation-delay: 0ms; }
  .card:nth-child(2) { animation-delay: 60ms; }
  .card:nth-child(3) { animation-delay: 120ms; }
  .card:nth-child(4) { animation-delay: 180ms; }
  .card:nth-child(5) { animation-delay: 240ms; }
  .card:nth-child(6) { animation-delay: 300ms; }

  @keyframes fadeUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
  }
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  .content-section {
    grid-template-columns: 1fr;
    padding-bottom: calc(var(--header-h) + 2rem);
  }
  .content-aside {
    border-right: none;
    border-bottom: 2px solid var(--clr-fg);
    padding-right: 0;
    padding-bottom: 1.5rem;
    margin-bottom: 0.5rem;
  }
  .hero-content--left { align-self: center; text-align: center; margin-left: 0; }
  .footer-cta { flex-direction: column; text-align: center; }
  .footer-bar { flex-direction: column; align-items: flex-start; gap: 0.5rem; }
  .card-grid { grid-template-columns: 1fr; }
  .grid-section { padding: 1.5rem 1rem 0; }
  .content-section { padding: 2rem 1rem calc(var(--header-h) + 2rem); }
}

@media (max-width: 480px) {
  .hero h1, .page-hero h1 { font-size: 1.6rem; }
  .hero-actions { flex-direction: column; align-items: stretch; }
  .hero-actions a { text-align: center; justify-content: center; }
  .brand { font-size: 0.85rem; }
  .header-inner { padding: 0 1rem; }
}