/* ============================================================
   广州星转科技有限公司 - 官网样式
   设计风格：德国工业风 × 科技感 / German Industrial + Tech-HUD
   ------------------------------------------------------------
   设计准则：
     · 形式追随功能 —— 去装饰、直角、无圆角、无渐变填充
     · 严格网格系统 —— 1px 细线分隔，模块化块面布局
     · 双强调色分层 —— 信号黄（近似 RAL 1003）用于品牌与行动
                      科技青用于数据 / 状态 / HUD 微元素，不抢主体
     · 技术感排版 —— 等宽字体标注编号、数据与标签
     · 克制的动效 —— 线性过渡、扫描线与状态点，尊重减少动效偏好
   ============================================================ */

:root {
  /* 中性色阶（工业灰阶） */
  --black: #111111;
  --coal: #161616;
  --steel-900: #1f1f1f;
  --steel-800: #262626;
  --steel-700: #333333;
  --steel-600: #4d4d4d;
  --steel-500: #6b6b6b;
  --steel-400: #9a9a9a;
  --steel-300: #c9c9c9;
  --line: #dcdcdc;
  --line-dark: #2e2e2e;
  --paper: #f2f2f0;
  --paper-dark: #e8e8e4;
  --white: #ffffff;

  /* 信号黄：德国工业标志色（RAL 1003 Signal Yellow 近似）—— 品牌与行动色 */
  --signal: #ffb400;
  --signal-deep: #d99a00;

  /* 科技青：仅用于数据 / 状态 / HUD 微元素
     --tech 用于深色底，--tech-deep 用于浅色底（保证对比度达标） */
  --tech: #00e5ff;
  --tech-deep: #0a7d95;
  --tech-dim: rgba(0, 229, 255, .38);

  --text: #161616;
  --text-muted: #5f5f5f;

  --font-sans: "Helvetica Neue", Helvetica, Arial, "PingFang SC", "HarmonyOS Sans SC", "Microsoft YaHei", "微软雅黑", sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", Menlo, Consolas, "Liberation Mono", "Courier New", monospace;

  --header-h: 68px;
  --ease: cubic-bezier(.2, .6, .3, 1);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-h);
}

body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--text);
  background: var(--white);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
h1, h2, h3, h4, p { margin: 0; }
ul, ol { margin: 0; padding: 0; list-style: none; }
button { font: inherit; cursor: pointer; border-radius: 0; }
input, textarea { border-radius: 0; }

/* 选区：信号黄，工业感的默认反馈 */
::selection { background: var(--signal); color: var(--black); }

/* 无障碍：键盘焦点必须清晰可见 */
a:focus-visible, button:focus-visible, input:focus-visible, textarea:focus-visible {
  outline: 3px solid var(--signal);
  outline-offset: 2px;
}

.container {
  width: min(1200px, 92%);
  margin-inline: auto;
}

/* ---------- 按钮：直角 + 大写字距 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 15px 34px;
  border: 2px solid var(--black);
  border-radius: 0;
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: .14em;
  text-transform: uppercase;
  transition: background .18s linear, color .18s linear, border-color .18s linear, box-shadow .18s linear;
}
.btn-primary {
  background: var(--signal);
  border-color: var(--signal);
  color: var(--black);
}
.btn-primary:hover {
  background: var(--black);
  border-color: var(--black);
  color: var(--signal);
  box-shadow: 0 0 26px rgba(255, 180, 0, .32);
}
.btn-ghost {
  background: transparent;
  border-color: rgba(255, 255, 255, .55);
  color: var(--white);
}
.btn-ghost:hover {
  background: var(--white);
  border-color: var(--white);
  color: var(--black);
}
.btn-block { width: 100%; }

/* ---------- 顶部导航：工业黑条 + 信号黄信号带 ---------- */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  height: var(--header-h);
  z-index: 100;
  background: rgba(17, 17, 17, 0);
  border-bottom: 1px solid rgba(255, 255, 255, 0);
  transition: background .2s linear, border-color .2s linear;
}
/* 页面顶部 4px 信号黄标识线 */
.site-header::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 4px;
  background: var(--signal);
}
.site-header.scrolled {
  background: rgba(17, 17, 17, .96);
  border-bottom-color: var(--line-dark);
  backdrop-filter: blur(8px);
}
.header-inner {
  height: 100%;
  display: flex;
  align-items: center;
  gap: 26px;
}
.brand { display: flex; align-items: center; gap: 12px; color: var(--white); }
.brand-logo {
  width: 40px; height: 40px;
  display: grid; place-items: center;
  background: var(--signal);
  color: var(--black);
  font-size: 19px;
  font-weight: 700;
  flex-shrink: 0;
}
.brand-text { display: flex; flex-direction: column; line-height: 1.3; }
.brand-text strong { font-size: 16px; font-weight: 700; letter-spacing: .06em; }
.brand-text small {
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: .22em;
  color: rgba(255, 255, 255, .5);
}

.main-nav { display: flex; gap: 2px; margin-left: auto; }
.nav-link {
  position: relative;
  color: rgba(255, 255, 255, .72);
  padding: 9px 15px;
  font-size: 14px;
  letter-spacing: .06em;
  transition: color .18s linear;
}
.nav-link::after {
  content: "";
  position: absolute;
  left: 15px; right: 15px; bottom: 2px;
  height: 2px;
  background: var(--signal);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .2s var(--ease);
}
.nav-link:hover { color: var(--white); }
.nav-link:hover::after,
.nav-link.active::after { transform: scaleX(1); }
.nav-link.active { color: var(--white); }

.header-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: transparent;
  border: 2px solid var(--signal);
  color: var(--signal);
  padding: 9px 22px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: .12em;
  transition: background .18s linear, color .18s linear;
}
/* 在线状态点：科技青呼吸闪烁 */
.header-cta::before {
  content: "";
  width: 6px; height: 6px;
  background: var(--tech);
  box-shadow: 0 0 8px var(--tech);
  animation: pulse 1.8s ease-in-out infinite;
  flex-shrink: 0;
}
.header-cta:hover { background: var(--signal); color: var(--black); }
.header-cta:hover::before { background: var(--black); box-shadow: none; }

/* 移动端汉堡按钮 */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 42px; height: 42px;
  background: transparent;
  border: 1px solid rgba(255, 255, 255, .3);
  padding: 10px;
}
.nav-toggle span {
  display: block;
  height: 2px;
  background: var(--white);
  transition: transform .22s var(--ease), opacity .22s linear;
}
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- 首屏 Hero：技术图纸 + HUD ---------- */
.hero {
  position: relative;
  min-height: 100dvh;
  display: flex;
  align-items: center;
  background: var(--coal);
  color: var(--white);
  overflow: hidden;
  padding: calc(var(--header-h) + 48px) 0 88px;
}
/* 左侧信号黄竖条 */
.hero::before {
  content: "";
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 6px;
  background: var(--signal);
}
/* 科技扫描线：自上而下循环（HUD 意象） */
.hero::after {
  content: "";
  position: absolute;
  left: 0; right: 0; top: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--tech-dim), transparent);
  animation: scanDown 8s linear infinite;
  pointer-events: none;
}
@keyframes scanDown {
  0% { transform: translateY(0); opacity: 0; }
  10% { opacity: 1; }
  90% { opacity: 1; }
  100% { transform: translateY(100dvh); opacity: 0; }
}

/* 网格底纹 + 右侧 45° 斜纹（铆接板意象） */
.hero-pattern {
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(255, 255, 255, .045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, .045) 1px, transparent 1px);
  background-size: 48px 48px;
}
.hero-pattern::after {
  content: "";
  position: absolute;
  top: 0; right: 0; bottom: 0;
  width: 34%;
  border-left: 1px solid rgba(255, 255, 255, .08);
  background-image: repeating-linear-gradient(
    45deg,
    rgba(255, 180, 0, .12) 0 2px,
    transparent 2px 13px
  );
}

/* 左栏文案 + 右栏状态面板 */
.hero-inner {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 306px;
  gap: 60px;
  align-items: center;
}
.hero-copy { max-width: 720px; }

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .26em;
  color: var(--signal);
  margin-bottom: 30px;
}
.hero-tag::before {
  content: "";
  width: 10px; height: 10px;
  background: var(--signal);
  flex-shrink: 0;
}
/* 光标闪烁：终端感 */
.hero-tag::after {
  content: "_";
  color: var(--tech);
  animation: blink 1.1s steps(1, end) infinite;
}
@keyframes blink { 0%, 49% { opacity: 1; } 50%, 100% { opacity: 0; } }

.hero-title {
  font-size: clamp(38px, 6.2vw, 74px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -.01em;
  color: var(--white);
}
.hero-title .accent { color: var(--signal); }

.hero-sub {
  margin: 28px 0 40px;
  max-width: 660px;
  color: rgba(255, 255, 255, .68);
  font-size: 16px;
}
.hero-actions { display: flex; gap: 18px; flex-wrap: wrap; }

/* 亮点列表：等宽字体 + 信号黄方块标记 */
.hero-points {
  display: flex;
  gap: 34px;
  flex-wrap: wrap;
  margin-top: 54px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: .08em;
  color: rgba(255, 255, 255, .6);
}
.hero-points li { display: flex; align-items: center; gap: 9px; }
.hero-points li::before {
  content: "";
  width: 8px; height: 8px;
  background: var(--signal);
  flex-shrink: 0;
}

/* ---------- 首屏科技面板：能力矩阵（HUD） ---------- */
.hero-panel {
  position: relative;
  border: 1px solid rgba(255, 255, 255, .14);
  background: rgba(255, 255, 255, .03);
  padding: 22px 22px 18px;
}
/* HUD 对角标记（科技青） */
.hero-panel::before,
.hero-panel::after {
  content: "";
  position: absolute;
  width: 14px; height: 14px;
  border-color: var(--tech);
  border-style: solid;
  pointer-events: none;
}
.hero-panel::before {
  top: -1px; left: -1px;
  border-width: 2px 0 0 2px;
}
.hero-panel::after {
  bottom: -1px; right: -1px;
  border-width: 0 2px 2px 0;
}
.panel-head {
  display: flex;
  align-items: center;
  gap: 9px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .22em;
  color: rgba(255, 255, 255, .75);
  padding-bottom: 14px;
  border-bottom: 1px solid rgba(255, 255, 255, .1);
}
/* 活动状态点：呼吸闪烁 */
.dot-live {
  width: 7px; height: 7px;
  background: var(--tech);
  box-shadow: 0 0 10px var(--tech);
  animation: pulse 1.8s ease-in-out infinite;
  flex-shrink: 0;
}
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: .25; } }

.panel-list { display: grid; }
.panel-list li {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 2px 10px;
  padding: 11px 0;
  border-bottom: 1px dashed rgba(255, 255, 255, .1);
}
.panel-list li:last-child { border-bottom: none; }
.panel-list .k {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: .1em;
  color: var(--tech);
}
.panel-list .v {
  grid-column: 1;
  font-size: 12.5px;
  color: rgba(255, 255, 255, .6);
}
.panel-list .st {
  grid-row: 1 / span 2;
  grid-column: 2;
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 600;
  letter-spacing: .12em;
  color: var(--tech);
  border: 1px solid var(--tech-dim);
  padding: 3px 7px;
}
.panel-foot {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid rgba(255, 255, 255, .1);
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: .12em;
  color: rgba(255, 255, 255, .42);
}

/* ---------- 数据一览：信号黄指标带 ---------- */
.stats {
  background: var(--signal);
  border-top: 1px solid var(--black);
  border-bottom: 1px solid var(--black);
}
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); }
.stat {
  padding: 34px 26px;
  border-left: 1px solid rgba(17, 17, 17, .18);
}
.stat:first-child { border-left: none; }
.stat strong {
  font-family: var(--font-mono);
  font-size: clamp(28px, 3.6vw, 42px);
  font-weight: 700;
  color: var(--black);
  font-variant-numeric: tabular-nums;
  letter-spacing: -.02em;
}
.stat span {
  font-family: var(--font-mono);
  font-size: 22px;
  font-weight: 700;
  color: var(--black);
  margin-left: 2px;
}
.stat p {
  margin-top: 2px;
  font-size: 13px;
  letter-spacing: .1em;
  color: rgba(17, 17, 17, .72);
}

/* ---------- 通用 Section：技术文档式标题 ---------- */
.section { padding: 104px 0; }
.section-head {
  text-align: left;
  margin-bottom: 56px;
  padding-bottom: 26px;
  border-bottom: 1px solid var(--line);
}
.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .3em;
  color: var(--steel-600);
  border-left: 3px solid var(--signal);
  padding-left: 11px;
  margin-bottom: 16px;
}
/* 方括号：终端 / 配置项意象 */
.section-tag::before,
.section-tag::after {
  font-family: var(--font-mono);
  color: var(--tech-deep);
  letter-spacing: 0;
}
.section-tag::before { content: "["; }
.section-tag::after { content: "]"; }

.section-title {
  font-size: clamp(28px, 3.6vw, 40px);
  font-weight: 700;
  letter-spacing: .01em;
  color: var(--black);
}
.section-desc {
  margin-top: 12px;
  color: var(--text-muted);
  font-size: 15.5px;
  max-width: 760px;
}

/* ---------- 关于我们 ---------- */
.about { background: var(--paper); }
.about-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 60px;
  align-items: start;
}
.about-text h3 {
  font-size: 23px;
  color: var(--black);
  margin-bottom: 18px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line);
}
.about-text p { color: var(--text-muted); margin-bottom: 14px; }
.about-list { margin-top: 26px; display: grid; gap: 12px; }
.about-list li {
  background: var(--white);
  border: 1px solid var(--line);
  border-left: 4px solid var(--signal);
  padding: 13px 20px;
  font-size: 15px;
}

/* 四宫格能力块：炭黑底 + 等宽编号 */
.about-cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  border: 1px solid var(--line-dark);
}
.about-card {
  position: relative;
  background: var(--steel-900);
  color: var(--white);
  padding: 30px 24px;
  border-right: 1px solid var(--line-dark);
  border-bottom: 1px solid var(--line-dark);
  transition: background .2s linear;
}
.about-card:nth-child(2n) { border-right: none; }
.about-card:nth-child(n+3) { border-bottom: none; }
.about-card:hover { background: var(--steel-800); }
.about-card .num {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .18em;
  color: var(--signal);
}
.about-card h4 { margin: 10px 0 6px; font-size: 17px; letter-spacing: .04em; }
.about-card p { font-size: 13px; color: rgba(255, 255, 255, .6); }

/* ---------- 核心业务：模块化卡片 + 信号黄扫描线 ---------- */
.business-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  border: 1px solid var(--line);
}
/* 六大业务板块：3 列 × 2 行 */
.business-grid--six { grid-template-columns: repeat(3, 1fr); }

.biz-card {
  position: relative;
  background: var(--white);
  padding: 38px 30px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
  transition: background .2s linear;
}
.biz-card:nth-child(4n) { border-right: none; }
.biz-card:nth-child(n+5) { border-bottom: none; }
/* 六宫格修正：每行 3 个 */
.business-grid--six .biz-card:nth-child(4n) { border-right: 1px solid var(--line); }
.business-grid--six .biz-card:nth-child(3n) { border-right: none; }
.business-grid--six .biz-card:nth-child(n+4) { border-bottom: none; }
.business-grid--six .biz-card:nth-child(-n+3) { border-bottom: 1px solid var(--line); }

/* 顶部信号黄扫描线 */
.biz-card::before {
  content: "";
  position: absolute;
  top: 0; left: 0;
  width: 0; height: 3px;
  background: var(--signal);
  transition: width .32s var(--ease);
}
.biz-card:hover::before { width: 100%; }
.biz-card:hover { background: var(--paper); }

/* 悬停时右下角出现 HUD 角标（科技青） */
.biz-card::after,
.product-card::after {
  content: "";
  position: absolute;
  right: 10px; bottom: 10px;
  width: 12px; height: 12px;
  border-right: 2px solid var(--tech-deep);
  border-bottom: 2px solid var(--tech-deep);
  opacity: 0;
  transition: opacity .2s linear;
  pointer-events: none;
}
.biz-card:hover::after,
.product-card:hover::after { opacity: 1; }

.biz-icon {
  width: 54px; height: 54px;
  display: grid; place-items: center;
  border: 1px solid var(--steel-300);
  background: var(--paper);
  color: var(--black);
  margin-bottom: 24px;
  transition: background .2s linear, border-color .2s linear, color .2s linear;
}
.biz-icon svg { width: 26px; height: 26px; }
.biz-card:hover .biz-icon {
  background: var(--signal);
  border-color: var(--signal);
  color: var(--black);
}
.biz-card h3 {
  font-size: 18px;
  color: var(--black);
  margin-bottom: 10px;
  letter-spacing: .02em;
}
.biz-card p { font-size: 14px; color: var(--text-muted); }

/* ---------- 产品方案：技术标牌式缩略图 ---------- */
.products { background: var(--paper); }
.product-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  border: 1px solid var(--line);
}
.product-card {
  position: relative;
  background: var(--white);
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  transition: background .2s linear;
}
.product-card:nth-child(3n) { border-right: none; }
.product-card:nth-child(n+4) { border-bottom: none; }
.product-card:hover { background: var(--paper); }

/* 缩略图：炭黑底 + 45° 斜纹 + 等宽标签（技术标牌意象） */
.product-thumb {
  position: relative;
  height: 172px;
  display: flex;
  align-items: flex-end;
  padding: 18px 20px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .22em;
  color: rgba(255, 255, 255, .78);
  background-image:
    repeating-linear-gradient(45deg, rgba(255, 255, 255, .04) 0 1px, transparent 1px 10px);
  border-bottom: 1px solid var(--line);
}
/* 左上角信号黄定位角标 */
.product-thumb::before {
  content: "";
  position: absolute;
  top: 16px; left: 16px;
  width: 11px; height: 11px;
  background: var(--signal);
}
/* 右上角技术刻度线（科技青） */
.product-thumb::after {
  content: "";
  position: absolute;
  top: 16px; right: 16px;
  width: 34px; height: 11px;
  background-image: repeating-linear-gradient(
    90deg,
    var(--tech-dim) 0 1px,
    transparent 1px 6px
  );
}

/* 各缩略图使用不同灰阶，保持工业单色基调 */
.thumb-1 { background-color: #1c1c1c; }
.thumb-2 { background-color: #232323; }
.thumb-3 { background-color: #1a1a1a; }
.thumb-4 { background-color: #262626; }
.thumb-5 { background-color: #1e1e1e; }
.thumb-6 { background-color: #212121; }

.product-body { padding: 24px 22px 28px; }
.product-body h3 { font-size: 17px; color: var(--black); margin-bottom: 8px; }
.product-body p { font-size: 14px; color: var(--text-muted); }

/* ---------- 合作优势：炭黑网格 + 点阵 ---------- */
.advantage {
  background: var(--coal);
  color: var(--white);
  background-image:
    radial-gradient(circle, rgba(0, 229, 255, .16) 1px, transparent 1.4px),
    linear-gradient(rgba(255, 255, 255, .035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, .035) 1px, transparent 1px);
  background-size: 24px 24px, 48px 48px, 48px 48px;
}
.advantage .section-head { border-bottom-color: var(--line-dark); }
.advantage .section-title { color: var(--white); }
.advantage .section-tag { color: rgba(255, 255, 255, .6); }
/* 深色底上改用亮青，保证可读性 */
.advantage .section-tag::before,
.advantage .section-tag::after { color: var(--tech); }
.advantage .section-desc { color: rgba(255, 255, 255, .55); }

.adv-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
  border: 1px solid var(--line-dark);
}
.adv-item {
  padding: 34px 26px;
  border-right: 1px solid var(--line-dark);
  transition: background .2s linear;
}
.adv-item:last-child { border-right: none; }
.adv-item:hover { background: rgba(255, 180, 0, .06); }
.adv-num {
  display: block;
  font-family: var(--font-mono);
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  color: var(--signal);
  margin-bottom: 18px;
  letter-spacing: -.03em;
}
.adv-item h3 { font-size: 17px; margin-bottom: 8px; color: var(--white); letter-spacing: .04em; }
.adv-item p { font-size: 13.5px; color: rgba(255, 255, 255, .6); }

/* ---------- 合作流程：方形序号 ---------- */
.process { background: var(--paper); }
.process-steps {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0;
  border: 1px solid var(--line);
  background: var(--white);
}
.process-steps li {
  position: relative;
  text-align: center;
  padding: 34px 18px;
  border-right: 1px solid var(--line);
}
.process-steps li:last-child { border-right: none; }
.process-steps span {
  width: 44px; height: 44px;
  display: grid; place-items: center;
  margin: 0 auto 16px;
  background: var(--signal);
  color: var(--black);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: .04em;
}
.process-steps h3 { font-size: 15.5px; color: var(--black); margin-bottom: 6px; letter-spacing: .02em; }
.process-steps p { font-size: 13px; color: var(--text-muted); }

/* ---------- 联系我们 ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 0.95fr 1.05fr;
  gap: 56px;
  align-items: start;
}
.contact-info {
  display: grid;
  gap: 0;
  border: 1px solid var(--line);
}
.contact-item {
  padding: 20px 24px;
  border-bottom: 1px solid var(--line);
  border-left: 4px solid var(--signal);
  background: var(--paper);
}
.contact-item:last-child { border-bottom: none; }
.contact-item h3 {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .2em;
  color: var(--steel-600);
  margin-bottom: 6px;
}
.contact-item p { color: var(--text); font-size: 15px; }
.contact-item a:hover { color: var(--signal-deep); }

.contact-form {
  background: var(--white);
  border: 1px solid var(--black);
  padding: 36px;
}
/* 表单抬头：等宽标签 */
.contact-form::before {
  content: "// INQUIRY_FORM";
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .2em;
  color: var(--tech-deep);
  padding-bottom: 14px;
  margin-bottom: 22px;
  border-bottom: 1px solid var(--line);
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.form-field { margin-bottom: 20px; display: flex; flex-direction: column; gap: 8px; }
.form-field label {
  font-size: 13px;
  font-weight: 600;
  letter-spacing: .1em;
  color: var(--black);
}
.form-field label span { color: var(--signal-deep); }
.form-field input, .form-field textarea {
  font: inherit;
  padding: 13px 14px;
  border: 1px solid var(--steel-300);
  background: var(--paper);
  transition: border-color .18s linear, background .18s linear;
}
.form-field input:focus, .form-field textarea:focus {
  outline: none;
  border-color: var(--black);
  background: var(--white);
  box-shadow: inset 0 -3px 0 var(--signal);
}
.form-tip { margin-top: 16px; font-size: 14px; min-height: 20px; }
.form-tip.ok { color: #1f6b3f; }
.form-tip.err { color: #b3261e; }

/* ---------- 页脚：工业铭牌 ---------- */
.site-footer {
  background: var(--black);
  color: rgba(255, 255, 255, .6);
  padding: 56px 0 34px;
  border-top: 4px solid var(--signal);
}
.footer-inner {
  display: grid;
  grid-template-columns: 1.2fr 1fr 1.1fr;
  gap: 36px;
  align-items: start;
}
.footer-brand strong {
  display: block;
  color: var(--white);
  font-size: 17px;
  letter-spacing: .06em;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line-dark);
  margin-bottom: 12px;
}
.footer-brand p { font-size: 14px; }
.footer-nav { display: flex; flex-direction: column; gap: 11px; font-size: 14px; }
.footer-nav a { letter-spacing: .06em; }
.footer-nav a:hover { color: var(--signal); }
.footer-meta {
  font-family: var(--font-mono);
  font-size: 12.5px;
  line-height: 1.9;
  text-align: right;
}
.footer-meta p { margin-bottom: 6px; }
.footer-meta a:hover { color: var(--signal); }
/* ICP 备案号：弱化显示，法规要求可见即可 */
.footer-meta .ipc a {
  opacity: .72;
  font-size: 12px;
  letter-spacing: .02em;
}
.footer-meta .ipc a:hover { opacity: 1; }

/* 经营范围铭牌区块 */
.scope {
  margin-top: 40px;
  padding-top: 26px;
  border-top: 1px solid var(--line-dark);
}
.scope h3 {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .24em;
  color: var(--signal);
  margin-bottom: 12px;
}
.scope p {
  font-size: 13px;
  color: rgba(255, 255, 255, .42);
  line-height: 1.95;
}

/* ---------- 返回顶部：方形 ---------- */
.back-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  width: 46px; height: 46px;
  border: none;
  background: var(--signal);
  color: var(--black);
  font-size: 19px;
  font-weight: 700;
  opacity: 0;
  visibility: hidden;
  transform: translateY(8px);
  transition: opacity .25s linear, transform .25s linear, visibility .25s;
  z-index: 90;
}
.back-top.show { opacity: 1; visibility: visible; transform: translateY(0); }
.back-top:hover { background: var(--black); color: var(--signal); }

/* ---------- 滚动进场：克制的机械位移 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity .5s linear, transform .5s var(--ease);
}
.reveal.visible { opacity: 1; transform: none; }

/* 无障碍：尊重系统「减少动态效果」偏好 */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .hero::after,
  .hero-tag::after,
  .dot-live,
  .header-cta::before { animation: none !important; }
  * { transition-duration: .01ms !important; }
}

/* ============================================================
   响应式适配
   ============================================================ */
@media (max-width: 992px) {
  .hero-inner { grid-template-columns: 1fr; gap: 44px; }
  .hero-panel { max-width: 440px; }
  .about-grid { grid-template-columns: 1fr; gap: 40px; }
  .business-grid,
  .business-grid--six { grid-template-columns: repeat(2, 1fr); }
  .product-grid { grid-template-columns: repeat(2, 1fr); }
  .adv-grid { grid-template-columns: repeat(2, 1fr); }
  .process-steps { grid-template-columns: repeat(3, 1fr); }
  .contact-grid { grid-template-columns: 1fr; gap: 40px; }
  .footer-inner { grid-template-columns: 1fr; gap: 28px; }
  .footer-meta { text-align: left; }

  /* 换行后重算网格边框，避免出现缺边 */
  .business-grid .biz-card,
  .business-grid--six .biz-card { border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
  .business-grid--six .biz-card:nth-child(2n) { border-right: none; }
  .business-grid--six .biz-card:nth-child(n+5) { border-bottom: none; }
  .product-grid .product-card { border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
  .product-grid .product-card:nth-child(2n) { border-right: none; }
  .product-grid .product-card:nth-child(n+5) { border-bottom: none; }
  .adv-grid .adv-item { border-right: 1px solid var(--line-dark); border-bottom: 1px solid var(--line-dark); }
  .adv-grid .adv-item:nth-child(2n) { border-right: none; }
  .adv-grid .adv-item:nth-child(n+3) { border-bottom: none; }

  /* 移动端导航：全宽抽屉 */
  .nav-toggle { display: flex; margin-left: auto; }
  .header-cta { display: none; }
  .main-nav {
    position: fixed;
    top: var(--header-h);
    left: 0; right: 0;
    flex-direction: column;
    gap: 0;
    background: rgba(17, 17, 17, .98);
    border-bottom: 3px solid var(--signal);
    padding: 8px 6%;
    transform: translateY(-12px);
    opacity: 0;
    visibility: hidden;
    transition: transform .22s var(--ease), opacity .22s linear, visibility .22s;
  }
  .main-nav.open { transform: none; opacity: 1; visibility: visible; }
  .main-nav .nav-link {
    padding: 14px 2px;
    font-size: 15.5px;
    border-bottom: 1px solid rgba(255, 255, 255, .08);
  }
  .main-nav .nav-link::after { display: none; }
  .main-nav .nav-link.active { color: var(--signal); }
}

@media (max-width: 640px) {
  .section { padding: 72px 0; }
  .hero-panel { max-width: none; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .stat { border-left: 1px solid rgba(17, 17, 17, .18); }
  .stat:nth-child(2n+1) { border-left: none; }
  .stat:nth-child(n+3) { border-top: 1px solid rgba(17, 17, 17, .18); }

  .business-grid,
  .business-grid--six,
  .product-grid,
  .adv-grid { grid-template-columns: 1fr; }

  /* 单列时保留右边框，仅去掉末项下边框 */
  .business-grid .biz-card,
  .business-grid--six .biz-card,
  .product-grid .product-card { border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); }
  .business-grid .biz-card:last-child,
  .business-grid--six .biz-card:last-child,
  .product-grid .product-card:last-child { border-bottom: none; }
  .adv-grid .adv-item { border-right: 1px solid var(--line-dark); border-bottom: 1px solid var(--line-dark); }
  .adv-grid .adv-item:last-child { border-bottom: none; }

  .process-steps { grid-template-columns: 1fr 1fr; }
  .process-steps li { border-bottom: 1px solid var(--line); }
  .process-steps li:nth-child(2n) { border-right: none; }
  .process-steps li:nth-last-child(-n+2) { border-bottom: none; }

  .form-row { grid-template-columns: 1fr; gap: 0; }
  .hero-actions .btn { width: 100%; }
  .hero-points { gap: 16px; flex-direction: column; }
  .product-thumb { height: 148px; }
}