/* =========================================================
   Beigong Automation — 独立站样式
   字体：Archivo Variable（标题）/ Inter Variable（正文），本地 @font-face
   ========================================================= */

/* ===== 可变字体引入（本地文件，可完全离线） ===== */
@font-face {
  font-family: 'Archivo';
  src: url('../fonts/archivo-var.woff2') format('woff2');
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Archivo';
  src: url('../fonts/archivo-italic-var.woff2') format('woff2');
  font-weight: 100 900;
  font-style: italic;
  font-display: swap;
}
@font-face {
  font-family: 'Inter';
  src: url('../fonts/inter-var.woff2') format('woff2');
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
}

/* ===== 设计变量 ===== */
:root {
  --ink-950: #0b0e13;
  --ink-900: #10141b;
  --ink-800: #161b25;
  --ink-700: #1e2531;
  --paper: #f4f2ec;
  --paper-2: #ece9e0;
  --text: #e9edf3;
  --muted: #9aa7b5;
  --text-dark: #171c24;
  --muted-dark: #5b6672;
  --accent: #f2600c;
  --accent-soft: #ff7a29;
  --line: rgba(255, 255, 255, 0.09);
  --line-dark: rgba(11, 14, 19, 0.12);
  --font-display: 'Archivo', 'Arial Narrow', sans-serif;
  --font-body: 'Inter', 'Segoe UI', sans-serif;
  --header-h: 76px;
  --radius: 14px;
  --shadow: 0 18px 50px rgba(11, 14, 19, 0.16);
}

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

html {
  scroll-padding-top: calc(var(--header-h) + 12px);
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.65;
  color: var(--text-dark);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
}

img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }

h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.08;
  letter-spacing: -0.01em;
  text-transform: uppercase;
}

.container {
  width: min(1180px, 100% - 48px);
  margin-inline: auto;
}
.container-narrow { width: min(860px, 100% - 48px); }

.section-dark { background: var(--ink-900); color: var(--text); }
.section-light { background: var(--paper); color: var(--text-dark); }

section { padding: clamp(72px, 9vw, 120px) 0; }

/* ===== 眉题 / 标题区 ===== */
.eyebrow {
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 18px;
}
.section-head { max-width: 780px; margin-bottom: clamp(40px, 5vw, 64px); }
.section-head h2 { font-size: clamp(30px, 4.4vw, 52px); margin-bottom: 18px; }
.section-head .lead { font-size: 17px; }
.accent { color: var(--accent); }

.section-dark .lead, .section-dark p { color: var(--muted); }
.section-light .lead, .section-light .section-head p { color: var(--muted-dark); }

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 15px 30px;
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  border-radius: 8px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.25s ease, box-shadow 0.25s ease, background 0.25s ease, border-color 0.25s ease;
}
.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 10px 28px rgba(242, 96, 12, 0.35);
}
.btn-primary:hover { background: var(--accent-soft); transform: translateY(-2px); }
.btn-ghost {
  border-color: rgba(255, 255, 255, 0.35);
  color: #fff;
  background: rgba(255, 255, 255, 0.04);
}
.btn-ghost:hover { border-color: #fff; transform: translateY(-2px); }
.btn-block { width: 100%; margin-top: 26px; }

/* ===== 顶部导航 ===== */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  height: var(--header-h);
  display: flex;
  align-items: center;
  transition: background 0.3s ease, box-shadow 0.3s ease, backdrop-filter 0.3s ease;
}
.site-header.scrolled {
  background: rgba(11, 14, 19, 0.92);
  backdrop-filter: blur(12px);
  box-shadow: 0 1px 0 var(--line);
}
.nav-wrap { display: flex; align-items: center; justify-content: space-between; gap: 24px; }

.brand { display: inline-flex; align-items: center; gap: 12px; color: var(--accent); }
.brand-mark { width: 34px; height: 34px; flex: none; }
.brand-text {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 17px;
  letter-spacing: 0.06em;
  color: #fff;
}
.brand-text em {
  font-style: normal;
  font-weight: 500;
  color: var(--accent);
  margin-left: 6px;
  letter-spacing: 0.18em;
  font-size: 12px;
}

.main-nav { display: flex; align-items: center; gap: 28px; }
.nav-link {
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.78);
  transition: color 0.2s ease;
  position: relative;
}
.nav-link:hover, .nav-link.active { color: #fff; }
.nav-link.active::after {
  content: '';
  position: absolute;
  left: 0; right: 0; bottom: -8px;
  height: 2px;
  background: var(--accent);
}
.nav-cta {
  padding: 11px 20px;
  background: var(--accent);
  color: #fff !important;
  border-radius: 6px;
}
.nav-cta:hover { background: var(--accent-soft); }
.nav-cta.active::after { display: none; }

/* 汉堡按钮（移动端） */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px; height: 44px;
  padding: 10px;
  background: none;
  border: 1px solid var(--line);
  border-radius: 8px;
  cursor: pointer;
}
.nav-toggle span {
  display: block;
  height: 2px;
  background: #fff;
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

/* ===== Hero ===== */
.hero {
  position: relative;
  min-height: 92vh;
  display: flex;
  align-items: center;
  padding: calc(var(--header-h) + 64px) 0 96px;
  color: #fff;
  overflow: hidden;
}
.hero-bg { position: absolute; inset: 0; z-index: -1; }
.hero-bg img { width: 100%; height: 100%; object-fit: cover; object-position: center; }
.hero-bg::after {
  content: '';
  position: absolute; inset: 0;
  background:
    linear-gradient(90deg, rgba(11, 14, 19, 0.92) 0%, rgba(11, 14, 19, 0.55) 55%, rgba(11, 14, 19, 0.25) 100%),
    linear-gradient(0deg, rgba(11, 14, 19, 0.85) 0%, rgba(11, 14, 19, 0) 40%);
}
.hero-content { max-width: 780px; }
.hero h1 {
  font-size: clamp(36px, 5.6vw, 68px);
  font-weight: 900;
  margin-bottom: 24px;
}
.hero .eyebrow { color: var(--accent-soft); }
.hero-sub {
  font-size: 18px;
  color: rgba(233, 237, 243, 0.85);
  max-width: 620px;
  margin-bottom: 36px;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 16px; margin-bottom: 44px; }
.hero-badges { display: flex; flex-wrap: wrap; gap: 12px 28px; }
.hero-badges li {
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(233, 237, 243, 0.7);
  padding-left: 14px;
  border-left: 2px solid var(--accent);
}

/* ===== 数据条 ===== */
.stats {
  background: var(--ink-950);
  border-block: 1px solid var(--line);
  padding: 44px 0;
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
}
.stat { text-align: center; }
.stat strong {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(34px, 4vw, 48px);
  font-weight: 900;
  color: #fff;
}
.stat strong i { font-style: normal; color: var(--accent); }
.stat span {
  font-size: 13px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

/* ===== 主推 PRDS（桌面通栏） ===== */
.featured .section-head { max-width: 900px; }

.featured-grid {
  display: grid;
  grid-template-columns: 1.08fr 1fr;
  gap: clamp(36px, 5vw, 72px);
  align-items: center;
}
.featured-media {
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  border: 1px solid var(--line);
}
.featured-media img { width: 100%; height: 100%; object-fit: cover; }
.featured-body .check-list { margin-bottom: 34px; }

.check-list li {
  position: relative;
  padding: 12px 0 12px 34px;
  border-bottom: 1px solid var(--line);
  color: var(--muted);
  font-size: 15px;
}
.section-light .check-list li { border-color: var(--line-dark); color: var(--muted-dark); }
.check-list li::before {
  content: '';
  position: absolute;
  left: 0; top: 17px;
  width: 16px; height: 16px;
  background: var(--accent);
  clip-path: polygon(14% 44%, 0 65%, 50% 100%, 100% 16%, 80% 0%, 43% 62%);
}

/* 规格条 */
.spec-strip {
  margin-top: clamp(40px, 5vw, 64px);
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}
.spec-strip > div { background: var(--ink-800); padding: 22px 18px; }
.spec-strip dt {
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 8px;
}
.spec-strip dd {
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 700;
  color: #fff;
}

/* ===== 产品网格（桌面 2×2） ===== */
.product-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px;
}
.product-card {
  background: #fff;
  border: 1px solid var(--line-dark);
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.product-card:hover { transform: translateY(-6px); box-shadow: var(--shadow); }
.product-media { aspect-ratio: 16 / 10; overflow: hidden; }
.product-media img {
  width: 100%; height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}
.product-card:hover .product-media img { transform: scale(1.04); }
.product-body { padding: 28px 28px 32px; display: flex; flex-direction: column; flex: 1; }
.tag {
  align-self: flex-start;
  font-family: var(--font-display);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--accent);
  border: 1px solid rgba(242, 96, 12, 0.4);
  border-radius: 999px;
  padding: 5px 14px;
  margin-bottom: 16px;
}
.product-body h3 { font-size: 21px; margin-bottom: 12px; }
.product-body > p { color: var(--muted-dark); font-size: 15px; margin-bottom: 18px; }
.product-body ul { margin-bottom: 24px; }
.product-body ul li {
  position: relative;
  padding: 7px 0 7px 22px;
  font-size: 14px;
  color: var(--muted-dark);
}
.product-body ul li::before {
  content: '';
  position: absolute;
  left: 2px; top: 14px;
  width: 8px; height: 8px;
  background: var(--accent);
  border-radius: 2px;
}
.card-link {
  margin-top: auto;
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-dark);
  display: inline-flex;
  gap: 10px;
  align-items: center;
  transition: color 0.2s ease, gap 0.2s ease;
}
.card-link:hover { color: var(--accent); gap: 14px; }

/* ===== 行业网格 ===== */
.industry-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.industry-card {
  background: var(--ink-800);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 32px 28px;
  transition: border-color 0.25s ease, transform 0.25s ease;
}
.industry-card:hover { border-color: rgba(242, 96, 12, 0.5); transform: translateY(-4px); }
.industry-card svg {
  width: 40px; height: 40px;
  color: var(--accent);
  margin-bottom: 20px;
}
.industry-card h3 { font-size: 17px; margin-bottom: 12px; text-transform: none; letter-spacing: 0; }
.industry-card p { font-size: 14px; }

/* ===== 能力与流程 ===== */
.cap-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(36px, 5vw, 72px);
  align-items: start;
  margin-bottom: clamp(48px, 6vw, 72px);
}
.cap-media {
  position: sticky;
  top: calc(var(--header-h) + 24px);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
}
.cap-media img { width: 100%; }
.cap-media figcaption {
  position: absolute;
  left: 0; right: 0; bottom: 0;
  padding: 18px 22px;
  font-size: 13px;
  letter-spacing: 0.06em;
  color: rgba(255, 255, 255, 0.9);
  background: linear-gradient(0deg, rgba(11, 14, 19, 0.8), transparent);
}
.process li { padding: 0 0 34px 34px; position: relative; }
.process li:not(:last-child)::before {
  content: '';
  position: absolute;
  left: 5px; top: 18px; bottom: 0;
  width: 1px;
  background: var(--line-dark);
}
.process li::after {
  content: '';
  position: absolute;
  left: 0; top: 6px;
  width: 11px; height: 11px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 5px rgba(242, 96, 12, 0.15);
}
.process strong {
  display: block;
  font-family: var(--font-display);
  font-size: 17px;
  font-weight: 800;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: 8px;
}
.process p { color: var(--muted-dark); font-size: 15px; }

.why {
  background: var(--ink-900);
  color: var(--text);
  border-radius: var(--radius);
  padding: clamp(32px, 4vw, 52px);
}
.why h3 { font-size: clamp(22px, 3vw, 30px); margin-bottom: 28px; }
.why-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px 32px;
}
.why-grid li {
  position: relative;
  padding-left: 24px;
  color: var(--muted);
  font-size: 15px;
}
.why-grid li::before {
  content: '';
  position: absolute;
  left: 0; top: 8px;
  width: 10px; height: 10px;
  background: var(--accent);
  border-radius: 2px;
}

/* ===== FAQ ===== */
.faq { border-top: 1px solid var(--line-dark); }
.faq-list details {
  background: #fff;
  border: 1px solid var(--line-dark);
  border-radius: 12px;
  margin-bottom: 14px;
  overflow: hidden;
}
.faq-list summary {
  cursor: pointer;
  list-style: none;
  padding: 22px 60px 22px 26px;
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  letter-spacing: 0.02em;
  position: relative;
  transition: color 0.2s ease;
}
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after {
  content: '+';
  position: absolute;
  right: 22px; top: 50%;
  transform: translateY(-50%);
  font-size: 24px;
  font-weight: 400;
  color: var(--accent);
  transition: transform 0.25s ease;
}
.faq-list details[open] summary { color: var(--accent); }
.faq-list details[open] summary::after { transform: translateY(-50%) rotate(45deg); }
.faq-list details p {
  padding: 0 26px 24px;
  color: var(--muted-dark);
  font-size: 15px;
  max-width: 92%;
}

/* ===== 联系 ===== */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1.15fr;
  gap: 28px;
}
.contact-card, .quote-panel {
  background: var(--ink-800);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(30px, 4vw, 44px);
}
.contact-card h3 { font-size: 26px; }
.contact-role { font-size: 14px; margin: 8px 0 28px; }
.contact-list li {
  padding: 16px 0;
  border-top: 1px solid var(--line);
}
.contact-list span {
  display: block;
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 6px;
}
.contact-list a {
  font-family: var(--font-display);
  font-size: 19px;
  font-weight: 700;
  color: #fff;
  transition: color 0.2s ease;
}
.contact-list a:hover { color: var(--accent-soft); }
.contact-list p { color: var(--text); font-size: 15px; }
.quote-panel h3 { font-size: 20px; margin-bottom: 20px; }
.quote-note { margin-top: 18px; font-size: 13px; text-align: center; }

/* ===== 页脚 ===== */
.site-footer {
  background: var(--ink-950);
  color: var(--muted);
  padding-top: clamp(56px, 7vw, 84px);
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.2fr;
  gap: 40px;
  padding-bottom: 48px;
}
.footer-brand p { font-size: 14px; margin-top: 16px; max-width: 340px; }
.footer-col h4 {
  font-size: 13px;
  letter-spacing: 0.18em;
  color: #fff;
  margin-bottom: 18px;
}
.footer-col a, .footer-col p {
  display: block;
  font-size: 14px;
  padding: 5px 0;
  color: var(--muted);
  transition: color 0.2s ease;
}
.footer-col a:hover { color: var(--accent-soft); }
.footer-legal {
  border-top: 1px solid var(--line);
  padding-block: 22px;
  font-size: 13px;
}

/* ===== 渐显动画（由 JS 触发 .is-visible） ===== */
.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.7s ease, transform 0.7s ease;
  will-change: opacity, transform;
}
.reveal.is-visible { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
  * { scroll-behavior: auto !important; }
}

/* =========================================================
   响应式规则
   ========================================================= */

/* ===== ≤960px 平板：主推产品上下堆叠，下方产品保持 2×2 ===== */
@media (max-width: 960px) {
  .nav-toggle { display: flex; }
  .main-nav {
    position: fixed;
    top: var(--header-h);
    left: 0; right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: rgba(11, 14, 19, 0.98);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid var(--line);
    padding: 12px 24px 20px;
    transform: translateY(-110%);
    opacity: 0;
    pointer-events: none;
    transition: transform 0.35s ease, opacity 0.35s ease;
  }
  .main-nav.open { transform: translateY(0); opacity: 1; pointer-events: auto; }
  .nav-link { padding: 14px 0; border-bottom: 1px solid var(--line); }
  .nav-link.active::after { display: none; }
  .nav-cta { margin-top: 14px; text-align: center; border-bottom: none; }
  .nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
  .nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
  .nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

  /* 主推 PRDS 改为上下堆叠 */
  .featured-grid { grid-template-columns: 1fr; }
  .featured-media { max-height: 460px; }

  /* 产品网格继续保持 2×2（不改动 .product-grid） */

  .spec-strip { grid-template-columns: repeat(3, 1fr); }
  .industry-grid { grid-template-columns: repeat(2, 1fr); }
  .cap-grid { grid-template-columns: 1fr; }
  .cap-media { position: static; }
  .why-grid { grid-template-columns: repeat(2, 1fr); }
  .contact-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

/* ===== ≤720px 移动端：所有产品模块单列堆叠 ===== */
@media (max-width: 720px) {
  .container { width: calc(100% - 36px); }

  .hero { min-height: auto; padding-bottom: 72px; }
  .hero-actions .btn { flex: 1 1 100%; }
  .hero-badges { gap: 10px 18px; }

  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 26px 12px; }

  /* 所有产品模块单列堆叠 */
  .product-grid { grid-template-columns: 1fr; }
  .spec-strip { grid-template-columns: repeat(2, 1fr); }
  .industry-grid { grid-template-columns: 1fr; }
  .why-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }

  .process li { padding-left: 26px; }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .brand-text { font-size: 15px; }
}