/* =========================================================
   HARVIN 产品官网 —— DAEDALI 品牌视觉（Identity 设计语言）
   暗色 / 黑白单色系 / 直角无阴影 / 40% 白细描边 / 悬停反转
   无彩色强调：--live = 白
   ========================================================= */
:root {
  --bg: #0e0e0f;          /* 页面主背景 */
  --bg-bleed: #131316;    /* 出血板块背景 */
  --text: #ffffff;
  --text-dim: rgba(255, 255, 255, .6);
  --line: rgba(255, 255, 255, .4);   /* 细描边 */
  --line-soft: rgba(255, 255, 255, .18);
  --live: #ffffff;        /* 无彩色强调（Identity 设计语言）：白 */
  --font: "HarmonyOS Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --content: 1280px;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  font-size: 20px;
  line-height: 1.7;
}

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

.container { width: min(var(--content), 90%); margin: 0 auto; }
.container-narrow { width: min(860px, 90%); margin: 0 auto; }

/* =========================================================
   按钮：透明底 + 细白描边，悬停黑白反转
   ========================================================= */
.btn {
  display: inline-block;
  padding: 14px 48px;
  background: transparent;
  border: 1px solid var(--line);
  color: var(--text);
  font-family: var(--font);
  font-size: 20px;
  cursor: pointer;
  transition: all .2s;
}
.btn:hover { background: #fff; color: #000; }
.btn:active { transform: scale(.95); }
.btn-ghost { border-color: transparent; }
.btn-ghost:hover { border-color: var(--line); background: #fff; }
.btn-light { border-color: #fff; }
.btn-center { display: block; margin: 48px auto 0; }
.btn-block { display: block; width: 100%; text-align: center; margin-top: 36px; }

.btn-mini {
  padding: 6px 24px;
  background: transparent;
  border: 1px solid var(--line);
  color: var(--text);
  font-size: 16px;
  cursor: pointer;
  transition: all .2s;
}
.btn-mini:hover { background: #fff; color: #000; }

/* =========================================================
   导航：透明固定，滚动后加深
   ========================================================= */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: rgba(0, 0, 0, 0);
  transition: background .3s;
}
.navbar.scrolled { background: rgba(0, 0, 0, .8); }
.nav-inner {
  width: min(var(--content), 92%);
  margin: 0 auto;
  height: 96px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.logo {
  font-size: 28px;
  font-weight: 700;
  letter-spacing: 4px;
}
.nav-links { display: flex; align-items: center; gap: 32px; }
.nav-links a {
  position: relative;
  font-size: 18px;
  line-height: 30px;
  white-space: nowrap;
  transition: color .2s;
}
/* 悬停下划线展开 */
.nav-links a::after {
  content: "";
  position: absolute;
  left: 0; bottom: -4px;
  width: 100%; height: 1px;
  background: #fff;
  transform: scale(0);
  transform-origin: left;
  transition: transform .2s;
}
.nav-links a:hover::after { transform: scale(1); }
.nav-cta { border: 1px solid var(--line); padding: 8px 24px; }
.nav-cta::after { display: none; }
.nav-cta:hover { background: #fff; color: #000; }
.nav-toggle { display: none; background: none; border: none; color: #fff; font-size: 28px; cursor: pointer; }

/* =========================================================
   首屏：全屏实拍视频背景（Identity 式：大图压暗 + 文字左下）
   ========================================================= */
.hero { position: relative; height: 100vh; min-height: 640px; overflow: hidden; background: #0a0a0b; }

.hero-media, .hero-media video, .hero-shade {
  position: absolute;
  inset: 0;
}
.hero-media video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: brightness(.55) saturate(.85);
}
/* 黑色渐变遮罩：左→右、下→上 双向压暗，保证文字可读 */
.hero-shade {
  background:
    linear-gradient(to top, #0e0e0f 2%, rgba(14, 14, 15, .25) 38%, rgba(14, 14, 15, .1) 60%, rgba(14, 14, 15, .45) 100%),
    linear-gradient(to right, rgba(14, 14, 15, .78), rgba(14, 14, 15, .25) 55%, rgba(14, 14, 15, .05));
}

.hero-content {
  position: relative;
  z-index: 4;
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;      /* Identity 式：文字沉底 */
  padding-bottom: 12vh;
  width: min(var(--content), 90%);
  margin: 0 auto;
}
.hero-kicker {
  font-size: 15px;
  letter-spacing: 8px;
  color: var(--text-dim);
  margin-bottom: 24px;
}
.hero h1 {
  font-size: clamp(44px, 5.5vw, 84px);
  line-height: 1.15;
  font-weight: 700;
  margin-bottom: 28px;
}
.hero-sub {
  color: var(--text-dim);
  font-size: 20px;
  max-width: 34em;
  margin-bottom: 44px;
}
.hero-actions { display: flex; gap: 24px; flex-wrap: wrap; }

/* 下滑提示（鼠标形状） */
.scroll-hint {
  position: absolute;
  left: 50%; bottom: 32px;
  transform: translateX(-50%);
  z-index: 5;
}
.mouse {
  display: block;
  width: 24px; height: 42px;
  border: 1px solid var(--line);
  border-radius: 12px;
  position: relative;
}
.wheel {
  position: absolute;
  left: 50%; top: 8px;
  width: 3px; height: 8px;
  background: #fff;
  transform: translateX(-50%);
  animation: wheel 1.8s infinite;
}
@keyframes wheel {
  0% { opacity: 1; top: 8px; }
  70% { opacity: 0; top: 22px; }
  100% { opacity: 0; top: 8px; }
}

/* =========================================================
   通用板块
   ========================================================= */
.section { padding: 120px 0; }
.section-bleed { background: var(--bg-bleed); }

.section-title {
  font-size: 48px;
  font-weight: 700;
  margin-bottom: 72px;
}
.section-title.left { text-align: left; }
.section-sub { text-align: center; color: var(--text-dim); margin: -48px 0 72px; }

/* =========================================================
   产品资讯：新闻列表
   ========================================================= */
.news-layout {
  display: flex;
  justify-content: space-between;
  gap: 48px;
  align-items: flex-start;
}
.news-left { flex: 1; min-width: 0; }

.news-item {
  display: flex;
  gap: 32px;
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
}
.news-cover {
  flex: none;
  width: 284px;
  height: 213px;
  background: linear-gradient(160deg, #1a1c26, #14151c);
  border: 1px solid var(--line-soft);
  display: grid;
  place-items: center;
  font-size: 64px;
  transition: border-color .2s;
}
.news-item:hover .news-cover { border-color: var(--line); }
/* Identity 式新闻行：日期 + 标题 + 箭头，hover 变白（无图片无卡片） */
.news-item {
  display: block;
  padding: 34px 8px;
  border-bottom: 1px solid var(--line);
  transition: background .2s;
}
.news-item:hover { background: rgba(255,255,255,.03); }
.news-item h3 {
  font-size: 26px;
  font-weight: 700;
  line-height: 1.45;
  transition: color .2s;
}
.news-item:hover h3 { color: #fff; }
.news-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 14px;
  color: var(--text-dim);
  font-size: 16px;
  letter-spacing: 1px;
}
.news-meta .btn-mini { display: none; }   /* 箭头替代按钮 */
.news-cover { display: none; }            /* 停用图片封面 */

.news-body { flex: 1; display: flex; flex-direction: column; justify-content: space-between; }
.news-body h3 {
  font-size: 32px;
  font-weight: 700;
  line-height: 1.4;
  transition: color .2s;
}
.news-item:hover .news-body h3 { color: var(--text-dim); }
.news-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 24px;
  color: var(--text-dim);
  font-size: 20px;
}

/* 右侧演示栏 */
.news-right { width: 308px; flex: none; }
.sub-title {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.live-dot {
  width: 10px; height: 10px;
  background: var(--live);
  border-radius: 50%;
  animation: pulse 1.6s infinite;
}
@keyframes pulse {
  0% { box-shadow: 0 0 0 0 rgba(255, 255, 255, .5); }
  70% { box-shadow: 0 0 0 10px rgba(255, 255, 255, 0); }
  100% { box-shadow: 0 0 0 0 rgba(255, 255, 255, 0); }
}

/* 演示栏真实视频（竖版 3:4 原生比例，不裁切） */
.stream-video {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  background: #000;
}
.stream-note .stream-info { padding: 16px 12px; }
.stream-note strong { font-size: 16px; }

.stream-card {
  padding: 4px;
  border: 1px solid var(--line);
  margin-bottom: 10px;
  transition: background .2s;
}
.stream-card:hover { background: rgba(255, 255, 255, .04); }
.stream-cover {
  width: 100%;
  height: 170px;
  background-size: cover;
  background-position: center;
  display: grid;
  place-items: center;
  position: relative;
}
.cover-s1 { background: linear-gradient(140deg, #1a2440, #101318); }
.cover-s2 { background: linear-gradient(140deg, #16302b, #101318); }
.cover-s3 { background: linear-gradient(140deg, #2a1f33, #101318); }
.play {
  width: 56px; height: 56px;
  border: 1px solid var(--line);
  display: grid;
  place-items: center;
  font-size: 20px;
  transition: all .2s;
}
.stream-card:hover .play { background: #fff; color: #000; }
.stream-info { display: flex; align-items: center; gap: 12px; padding: 12px 8px; }
.avatar {
  width: 48px; height: 48px;
  border: 1px solid var(--line);
  display: grid;
  place-items: center;
  font-size: 16px;
  font-weight: 700;
  color: var(--text-dim);
  flex: none;
}
.stream-text { display: flex; flex-direction: column; }
.stream-text strong { font-size: 18px; }
.views { font-size: 16px; color: var(--text-dim); }

/* =========================================================
   产品简介：全宽出血，左文右视频
   ========================================================= */
.bleed-inner {
  width: min(var(--content), 90%);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  gap: 64px;
  align-items: center;
}
.intro-text { flex: 1; }
.intro-text p { color: var(--text-dim); margin-bottom: 20px; }
.spec-brief { display: flex; gap: 16px; margin: 28px 0 36px; flex-wrap: wrap; }
.spec-brief li {
  border: 1px solid var(--line);
  padding: 8px 20px;
  font-size: 18px;
  color: var(--text-dim);
}
.intro-media { flex: none; }
.media-frame {
  width: 553px;
  height: 400px;
  border: 1px solid var(--line);
  background: linear-gradient(160deg, #161a26, #101218);
  display: grid;
  place-items: center;
  font-size: 56px;
  cursor: pointer;
  transition: all .2s;
  position: relative;
}
.media-frame span {
  position: absolute;
  bottom: 20px;
  font-size: 15px;
  color: var(--text-dim);
  letter-spacing: 2px;
}
.media-frame:hover { border-color: #fff; }

/* =========================================================
   精选视频：3列网格
   ========================================================= */
.video-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}
.video-card { display: block; }
.video-cover {
  height: 234px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line-soft);
  transition: border-color .2s;
  background-size: cover;
  background-position: center;
}
.cover-v1 { background: linear-gradient(140deg, #1a2033, #101318); }
.cover-v2 { background: linear-gradient(140deg, #14283a, #101318); }
.cover-v3 { background: linear-gradient(140deg, #1b1a2e, #101318); }
.cover-v4 { background: linear-gradient(140deg, #17231f, #101318); }
.cover-v5 { background: linear-gradient(140deg, #241a2c, #101318); }
.video-card:hover .video-cover { border-color: #fff; }
.video-card:hover .play { background: #fff; color: #000; }
.video-card p {
  padding: 20px 32px 0 0;
  font-size: 20px;
  line-height: 32px;
  color: var(--text);
}
.video-more {
  border: 1px solid var(--line);
  display: grid;
  place-items: center;
  min-height: 300px;
  color: var(--text-dim);
}

/* =========================================================
   技术参数：细线表格
   ========================================================= */
.spec-table {
  width: 100%;
  border-collapse: collapse;
}
.spec-table td {
  padding: 22px 24px;
  border-bottom: 1px solid var(--line);
  font-size: 20px;
}
.spec-table tr:first-child td { border-top: 1px solid var(--line); }
.spec-table td:first-child { color: var(--text-dim); width: 40%; }

/* =========================================================
   价格方案
   ========================================================= */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}
.price-card {
  position: relative;
  border: 1px solid var(--line);
  padding: 48px 36px;
  transition: all .2s;
}
.price-card:hover { border-color: #fff; }
.price-card.featured { border-color: #fff; }
.price-tag {
  position: absolute;
  top: -16px; left: 24px;
  background: var(--bg);
  padding: 0 12px;
  font-size: 16px;
  color: var(--live);
  letter-spacing: 2px;
}
.price-card h3 { font-size: 24px; color: var(--text-dim); }
.price { font-size: 56px; font-weight: 700; margin: 16px 0 8px; }
.price-card ul { border-top: 1px solid var(--line-soft); }
.price-card li {
  padding: 14px 0;
  border-bottom: 1px solid var(--line-soft);
  color: var(--text-dim);
  font-size: 18px;
}

/* =========================================================
   常见问题：细线折叠
   ========================================================= */
.faq-item { border-bottom: 1px solid var(--line); }
.faq-item:first-of-type { border-top: 1px solid var(--line); }
.faq-q {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 28px 8px;
  background: none;
  border: none;
  color: var(--text);
  font-family: var(--font);
  font-size: 22px;
  cursor: pointer;
  text-align: left;
}
.faq-icon {
  font-size: 28px;
  font-weight: 300;
  color: var(--text-dim);
  transition: transform .2s;
}
.faq-item.open .faq-icon { transform: rotate(45deg); }
.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height .3s ease;
}
.faq-item.open .faq-a { max-height: 300px; }
.faq-a p { padding: 0 8px 28px; color: var(--text-dim); }

/* =========================================================
   CTA
   ========================================================= */
.cta { padding: 140px 0; text-align: center; background: var(--bg-bleed); border-top: 1px solid var(--line-soft); }
.cta h2 { font-size: 48px; font-weight: 700; margin-bottom: 16px; }
.cta p { color: var(--text-dim); margin-bottom: 48px; }
.cta-actions { display: flex; gap: 24px; justify-content: center; flex-wrap: wrap; }

/* =========================================================
   页脚
   ========================================================= */
.footer { padding: 72px 0 32px; background: #0a0a0b; }
.footer-grid {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 48px;
  flex-wrap: wrap;
  padding-bottom: 48px;
  border-bottom: 1px solid var(--line-soft);
}
.footer-brand p { color: var(--text-dim); margin-top: 12px; font-size: 18px; }
.footer-links { display: flex; gap: 32px; flex-wrap: wrap; }
.footer-links a { color: var(--text-dim); font-size: 18px; transition: color .2s; }
.footer-links a:hover { color: #fff; }
.footer-social { display: flex; gap: 12px; }
.footer-social a {
  width: 56px; height: 56px;
  border: 1px solid var(--line);
  display: grid;
  place-items: center;
  font-size: 15px;
  color: var(--text-dim);
  transition: all .2s;
}
.footer-social a:hover { background: #fff; color: #000; }
.copyright { margin-top: 28px; text-align: center; color: var(--text-dim); font-size: 16px; }

/* =========================================================
   滚动渐入（自实现 AOS 等效）
   ========================================================= */
[data-reveal] {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity .6s ease, transform .6s ease;
}
[data-reveal].revealed { opacity: 1; transform: translateY(0); }

/* =========================================================
   响应式
   ========================================================= */
@media (max-width: 1100px) {
  .news-layout { flex-direction: column; }
  .news-right { width: 100%; }
  .bleed-inner { flex-direction: column; }
  .media-frame { width: 100%; max-width: 553px; }
}

/* 导航项较多（子页含返回按钮），1150px 起收进汉堡菜单，避免与 LOGO 重叠 */
@media (max-width: 1150px) {
  .nav-toggle { display: block; }
  .nav-links {
    position: absolute;
    top: 96px; left: 0; right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 20px;
    padding: 32px 5%;
    background: rgba(10, 10, 11, .96);
    border-bottom: 1px solid var(--line-soft);
    display: none;
  }
  .nav-links.open { display: flex; }
}

@media (max-width: 860px) {
  body { font-size: 18px; }
  .section { padding: 72px 0; }
  .section-title { font-size: 34px; margin-bottom: 48px; }
  .video-grid, .pricing-grid { grid-template-columns: 1fr; }
  .news-item { flex-direction: column; gap: 20px; }
  .news-cover { width: 100%; height: 200px; }
  .nav-toggle { display: block; }
  .nav-links {
    position: absolute;
    top: 96px; left: 0; right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 20px;
    padding: 32px 5%;
    background: rgba(10, 10, 11, .96);
    border-bottom: 1px solid var(--line-soft);
    display: none;
  }
  .nav-links.open { display: flex; }
  .hero h1 { font-size: 44px; }
}

/* =========================================================
   子页横幅（多页站新增）
   ========================================================= */
.page-hero {
  height: 420px;
  display: flex;
  align-items: center;
  background:
    radial-gradient(900px 500px at 75% 20%, rgba(80, 110, 247, .16), transparent 65%),
    radial-gradient(600px 400px at 15% 90%, rgba(34, 211, 238, .08), transparent 60%),
    var(--bg-bleed);
  border-bottom: 1px solid var(--line-soft);
}
.page-hero-sm { height: 320px; }
.page-hero h1 {
  font-size: 56px;
  font-weight: 700;
  margin-top: 12px;
}
.crumb {
  font-size: 16px;
  color: var(--text-dim);
  letter-spacing: 1px;
}
.crumb a { color: var(--text-dim); transition: color .2s; }
.crumb a:hover { color: #fff; }

/* =========================================================
   文章详情页
   ========================================================= */
.btn-back {
  display: inline-block;
  margin-bottom: 48px;
  color: var(--text-dim);
  font-size: 18px;
  transition: color .2s;
}
.btn-back:hover { color: #fff; }

.article-head { border-bottom: 1px solid var(--line); padding-bottom: 32px; margin-bottom: 40px; }
.article-title {
  font-size: 40px;
  line-height: 1.4;
  font-weight: 700;
  margin-bottom: 16px;
}
.article-meta { color: var(--text-dim); font-size: 18px; }
.article-body p { color: var(--text-dim); margin-bottom: 24px; }
.article-body h3 {
  font-size: 26px;
  margin: 48px 0 20px;
  padding-left: 16px;
  border-left: 3px solid #fff;
}

/* 上一篇 / 下一篇 */
.article-nav {
  display: flex;
  justify-content: space-between;
  gap: 32px;
  margin-top: 72px;
  padding-top: 40px;
  border-top: 1px solid var(--line);
}
.article-nav a {
  color: var(--text-dim);
  font-size: 16px;
  transition: color .2s;
  max-width: 45%;
}
.article-nav a.next { text-align: right; margin-left: auto; }
.article-nav a:hover { color: #fff; }
.article-nav strong {
  display: block;
  font-size: 19px;
  color: var(--text);
  margin-top: 8px;
  font-weight: 600;
}

/* =========================================================
   关于我们页
   ========================================================= */
.about-intro { max-width: 860px; }
.about-intro p { color: var(--text-dim); margin-bottom: 20px; }

.concept-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}
.concept-card {
  border: 1px solid var(--line);
  padding: 40px 32px;
  transition: border-color .2s;
}
.concept-card:hover { border-color: #fff; }
.concept-card h3 { font-size: 24px; margin-bottom: 16px; }
.concept-card p { color: var(--text-dim); font-size: 18px; }

/* 时间线（方形节点，延续无圆角语言） */
.timeline {
  border-left: 1px solid var(--line);
  margin-left: 5px;
  padding-left: 44px;
}
.timeline-item { position: relative; padding-bottom: 56px; }
.timeline-item:last-child { padding-bottom: 0; }
.timeline-item::before {
  content: "";
  position: absolute;
  left: -49px;
  top: 10px;
  width: 9px; height: 9px;
  background: #fff;
}
.timeline-item .time {
  color: var(--text-dim);
  font-size: 16px;
  letter-spacing: 2px;
}
.timeline-item h3 { font-size: 24px; margin: 8px 0 10px; }
.timeline-item p { color: var(--text-dim); }

/* =========================================================
   联系我们页
   ========================================================= */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: start;
}
.contact-info .section-title { margin-bottom: 40px; }
.info-row {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  padding: 22px 8px;
  border-bottom: 1px solid var(--line);
}
.info-row:first-of-type { border-top: 1px solid var(--line); }
.info-label { color: var(--text-dim); flex: none; }
.info-value { text-align: right; }

.contact-form .section-title { margin-bottom: 40px; }
.contact-form input,
.contact-form textarea {
  width: 100%;
  background: transparent;
  border: 1px solid var(--line);
  color: var(--text);
  font-family: var(--font);
  font-size: 18px;
  padding: 16px 20px;
  margin-bottom: 20px;
  resize: vertical;
  transition: border-color .2s;
}
.contact-form input::placeholder,
.contact-form textarea::placeholder { color: var(--text-dim); }
.contact-form input:focus,
.contact-form textarea:focus { outline: none; border-color: #fff; }
.contact-form .btn { margin-top: 8px; }
.form-tip { margin-top: 16px; font-size: 14px; color: var(--text-dim); text-align: center; }

/* =========================================================
   左上角返回按钮（子页，延续直角描边/悬停反转语言）
   ========================================================= */
.nav-left { display: flex; align-items: center; gap: 20px; }
.back-btn {
  width: 44px;
  height: 44px;
  flex: none;
  background: transparent;
  border: 1px solid var(--line);
  color: var(--text);
  font-size: 20px;
  line-height: 1;
  font-family: var(--font);
  cursor: pointer;
  transition: all .2s;
}
.back-btn:hover { background: #fff; color: #000; }
.back-btn:active { transform: scale(.95); }

/* 子页响应式补充 */
@media (max-width: 860px) {
  .page-hero { height: 300px; }
  .page-hero h1 { font-size: 38px; }
  .article-title { font-size: 28px; }
  .article-body h3 { font-size: 22px; }
  .concept-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .article-nav { flex-direction: column; }
  .article-nav a, .article-nav a.next { max-width: 100%; text-align: left; margin-left: 0; }
}

/* =========================================================
   HARVIN 扩展组件
   ========================================================= */

/* 产品简介区视频 */
.media-video {
  display: block;
  width: 420px;
  max-width: 100%;
  height: auto;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  background: #000;
  border: 1px solid var(--line);
}

/* 精选视频区真实视频（竖版原生比例，覆盖 .video-cover 固定高度） */
.video-real {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  background: #000;
}

/* 两代路线 / 大卡片 */
.concept-grid-two { grid-template-columns: repeat(2, 1fr); }
.concept-card-lg { padding: 48px 40px; }
.card-tag {
  display: inline-block;
  color: var(--text-dim);
  font-size: 13px;
  letter-spacing: 4px;
  margin-bottom: 20px;
}
.card-list { margin-top: 20px; }
.card-list li {
  padding: 14px 0;
  border-bottom: 1px solid var(--line-soft);
  color: var(--text-dim);
  font-size: 18px;
}
.card-list li strong {
  color: var(--text);
  margin-right: 12px;
  font-weight: 600;
}
.card-note {
  margin-top: 20px;
  font-size: 15px;
  color: var(--text-dim);
  border-left: 1px solid var(--line);
  padding-left: 14px;
}

/* 板块脚注（工程边界 / 验证说明） */
.section-note {
  margin-top: 56px;
  text-align: center;
  color: var(--text-dim);
  font-size: 15px;
  line-height: 1.8;
}

/* OODA 流程条 */
.ooda-flow {
  display: flex;
  align-items: stretch;
  gap: 12px;
  margin-top: 72px;
  flex-wrap: wrap;
  justify-content: center;
}
.ooda-step {
  flex: 1;
  min-width: 180px;
  border: 1px solid var(--line);
  padding: 20px 20px 18px;
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 1px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.ooda-step small {
  font-weight: 400;
  font-size: 14px;
  color: var(--text-dim);
  line-height: 1.6;
  letter-spacing: 0;
}
.ooda-arrow {
  align-self: center;
  color: var(--text-dim);
  font-size: 22px;
}

/* 频率标签（技术架构卡片） */
.concept-card .freq {
  display: inline-block;
  color: var(--text-dim);
  font-size: 14px;
  letter-spacing: 4px;
  margin-bottom: 16px;
}

/* 团队卡片（关于我们） */
.founder-card { display: flex; gap: 28px; align-items: flex-start; }
.avatar-lg {
  flex: none;
  width: 88px;
  height: 88px;
  border: 1px solid var(--line);
  display: grid;
  place-items: center;
  font-size: 40px;
  font-weight: 700;
  color: var(--text-dim);
}
.founder-body h3 { font-size: 24px; margin-bottom: 12px; }
.founder-body h3 small {
  display: block;
  font-size: 16px;
  font-weight: 400;
  color: var(--text-dim);
  margin-top: 6px;
  letter-spacing: 1px;
}
.founder-cred {
  font-size: 15px;
  color: var(--text-dim);
  border-bottom: 1px solid var(--line-soft);
  padding-bottom: 14px;
  margin-bottom: 14px;
  line-height: 1.8;
}
.founder-body > p:last-child { color: var(--text-dim); font-size: 18px; }

/* 响应式补充 */
@media (max-width: 1100px) {
  .concept-grid-two { grid-template-columns: 1fr; }
  .ooda-flow { flex-direction: column; }
  .ooda-arrow { transform: rotate(90deg); text-align: center; }
}
@media (max-width: 860px) {
  .founder-card { flex-direction: column; }
  .media-video { width: 100%; max-width: 420px; margin: 0 auto; }
}

/* =========================================================
   微信二维码弹窗（页脚「微信」触发）
   ========================================================= */
.qr-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, .88);
  display: none;
  place-items: center;
  z-index: 200;
  cursor: pointer;
}
.qr-overlay.show { display: grid; }
.qr-box {
  background: var(--bg-bleed);
  border: 1px solid var(--line);
  padding: 36px;
  text-align: center;
  cursor: default;
}
.qr-box img {
  width: 280px;
  height: 280px;
  object-fit: contain;
  display: block;
  background: #fff;
}
.qr-box p {
  margin-top: 20px;
  color: var(--text-dim);
  font-size: 16px;
  letter-spacing: 2px;
}

/* =========================================================
   横向分隔（Identity 式 40% 白细横线）
   ========================================================= */

/* 板块标题下通栏横线：所有 section 的标题区与内容区横向分隔 */
.section-title {
  font-size: 48px;
  font-weight: 700;
  margin-bottom: 72px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--line);
}
.section-title.left { text-align: left; }

/* 堆叠布局（窄屏）：上下块之间横向分隔线 */
@media (max-width: 1100px) {
  .intro-text { padding-bottom: 56px; border-bottom: 1px solid var(--line); margin-bottom: 56px; }
  .concept-grid-two > .concept-card + .concept-card {
    padding-top: 48px; border-top: 1px solid var(--line); margin-top: 8px;
  }
  .contact-info { padding-bottom: 56px; border-bottom: 1px solid var(--line); margin-bottom: 56px; }
}

/* 宽屏双栏时：视频/卡片顶部与标题横线呼应，保持横向节奏 */
@media (min-width: 1101px) {
  .concept-grid-two {
    border-top: 1px solid var(--line-soft);
    padding-top: 56px;
  }
}