/* ==========================================================================
   机智驱动 Witdriven 官网样式
   深色科技风 · 移动优先 · 响应式断点：1024 / 768 / 480
   ========================================================================== */

/* ---------- 设计变量 ---------- */
:root {
  --bg-dark: #0b111c;        /* 深色板块背景 */
  --bg-dim: #f5f7fa;         /* 浅色板块背景（明暗交替） */
  --bg-card: #121a2a;        /* 深色卡片 */
  --text-dark: #e8edf5;      /* 深色板块正文 */
  --text-dim: #33404f;       /* 浅色板块正文 */
  --text-muted: #8b95a5;     /* 次级文字 */
  --accent: #00e5a8;         /* 品牌主色（科技青绿） */
  --accent-deep: #00b383;
  --border-dark: rgba(255, 255, 255, 0.08);
  --radius: 14px;
  --container: 1200px;
  --header-h: 72px;
  --shadow: 0 10px 40px rgba(0, 0, 0, 0.35);
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

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

html {
  scroll-behavior: smooth;
  /* 锚点定位时预留吸顶导航高度，避免标题被遮挡 */
  scroll-padding-top: calc(var(--header-h) + 12px);
}

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI", system-ui, -apple-system, sans-serif;
  line-height: 1.7;
  color: var(--text-dark);
  background: var(--bg-dark);
  -webkit-font-smoothing: antialiased;
}

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

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

ul {
  list-style: none;
}

.container {
  width: min(100% - 2.5rem, var(--container));
  margin-inline: auto;
}

/* ---------- 无障碍 ---------- */
/* 跳转链接：平时隐藏，键盘聚焦时可见 */
.skip-link {
  position: absolute;
  top: -100px;
  left: 1rem;
  z-index: 1000;
  padding: 0.6rem 1rem;
  background: var(--accent);
  color: #04120c;
  font-weight: 700;
  border-radius: 0 0 8px 8px;
}

.skip-link:focus {
  top: 0;
}

/* 全站焦点样式：键盘可见，鼠标点击不干扰 */
a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

/* 顶部导航例外：点击锚点跳转后链接保持焦点，全局绿色矩形描边会一直
   显示（如「关于我们」上的绿框）。这里去掉矩形，键盘/点击焦点统一
   改用下方绿色下划线呈现，视觉一致且不残留。 */
.primary-nav a:focus-visible {
  outline: none;
}

/* ---------- 顶部导航 ---------- */
.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  height: var(--header-h);
  transition: background 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

/* 滚动后导航加背景，保证文字可读性（js/main.js 切换类名） */
.site-header.is-scrolled {
  background: rgba(11, 17, 28, 0.88);
  backdrop-filter: blur(12px);
  box-shadow: 0 1px 0 var(--border-dark);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  height: var(--header-h);
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
}

.brand-logo {
  flex: none;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
  color: #fff;
}

.brand-text strong {
  font-size: 1.15rem;
  letter-spacing: 0.05em;
}

.brand-text em {
  font-style: normal;
  font-size: 0.65rem;
  letter-spacing: 0.32em;
  color: var(--accent);
}

/* 桌面导航 */
.primary-nav > ul {
  display: flex;
  align-items: center;
  gap: 1.8rem;
}

.primary-nav a {
  font-size: 0.95rem;
  color: rgba(232, 237, 245, 0.85);
  position: relative;
  padding: 0.4rem 0;
  transition: color 0.25s var(--ease);
}

.primary-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 2px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s var(--ease);
}

.primary-nav a:hover,
.primary-nav a:focus-visible {
  color: #fff;
}

.primary-nav a:hover::after,
.primary-nav a:focus-visible::after {
  transform: scaleX(1);
}

/* ---------- 语言下拉菜单 ---------- */
/* 锚点容器：相对定位使下拉菜单可用 absolute */
.lang-menu {
  position: relative;
}

/* 触发按钮：去掉胶囊边框，仅显示「当前语言 + 下拉箭头」文字 */
.lang-trigger {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.45rem 0.2rem;
  background: none;
  border: 0;
  border-radius: 0;
  color: rgba(232, 237, 245, 0.85);
  font-size: 0.95rem;
  font-family: inherit;
  cursor: pointer;
  transition: color 0.25s var(--ease);
}

.lang-trigger:hover,
.lang-trigger[aria-expanded="true"] {
  color: var(--accent);
}

.lang-trigger:focus-visible {
  outline: none;
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 6px;
  text-decoration-thickness: 2px;
}

/* 当前语言文字 + 箭头小图标 */
.lang-current {
  font-weight: 500;
  letter-spacing: 0.02em;
}

.lang-caret {
  width: 10px;
  height: 6px;
  transition: transform 0.25s var(--ease);
}

.lang-trigger[aria-expanded="true"] .lang-caret {
  transform: rotate(180deg);
}

/* 下拉菜单：绝对定位浮在导航下方 */
.lang-dropdown {
  position: absolute;
  top: calc(100% + 0.6rem);
  right: 0;
  min-width: 160px;
  margin: 0;
  padding: 0.4rem;
  list-style: none;
  background: rgba(8, 14, 26, 0.92);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid rgba(232, 237, 245, 0.08);
  border-radius: 12px;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.4);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-6px);
  transition: opacity 0.2s var(--ease), transform 0.2s var(--ease),
    visibility 0s linear 0.2s;
  z-index: 60;
}

/* 展开状态：可见 + 重置 visibility 过渡延时 */
.lang-menu.is-open .lang-dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
  transition: opacity 0.2s var(--ease), transform 0.2s var(--ease),
    visibility 0s linear 0s;
}

.lang-dropdown li {
  margin: 0;
}

.lang-dropdown a {
  display: block;
  padding: 0.6rem 0.9rem;
  font-size: 0.92rem;
  color: rgba(232, 237, 245, 0.85);
  border-radius: 8px;
  transition: background 0.2s var(--ease), color 0.2s var(--ease);
}

.lang-dropdown a::after {
  display: none; /* 下拉项不需要下划线动效 */
}

.lang-dropdown a:hover,
.lang-dropdown a:focus-visible {
  background: rgba(0, 229, 168, 0.12);
  color: var(--accent);
}

/* 当前语言项：菜单里加高亮 */
.lang-dropdown a[aria-current="page"] {
  color: var(--accent);
  background: rgba(0, 229, 168, 0.08);
}

/* 汉堡按钮：仅移动端显示 */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 0.5rem;
  background: none;
  border: 0;
  cursor: pointer;
}

.nav-toggle span {
  width: 22px;
  height: 2px;
  background: #fff;
  transition: transform 0.3s var(--ease), opacity 0.3s var(--ease);
}

.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);
}

/* ---------- Hero 首屏 ---------- */
.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100dvh; /* 移动端浏览器地址栏动态高度 */
  display: flex;
  align-items: center;
  overflow: hidden;
  padding: calc(var(--header-h) + 3rem) 0 4rem;
}

/* 纯 CSS 动效背景：网格 + 双光晕（后续可替换为视频封面） */
.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  background:
    radial-gradient(ellipse 80% 60% at 70% 20%, rgba(0, 229, 168, 0.12), transparent 60%),
    radial-gradient(ellipse 60% 50% at 20% 80%, rgba(56, 132, 255, 0.10), transparent 60%),
    var(--bg-dark);
}

.hero-grid {
  position: absolute;
  inset: -1px;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 90% 70% at 50% 40%, #000 30%, transparent 75%);
  animation: grid-drift 24s linear infinite;
}

@keyframes grid-drift {
  to {
    background-position: 56px 56px, 56px 56px;
  }
}

.hero-glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(70px);
  opacity: 0.55;
}

.glow-a {
  width: 420px;
  height: 420px;
  background: rgba(0, 229, 168, 0.28);
  top: -120px;
  right: -80px;
  animation: glow-float 9s ease-in-out infinite alternate;
}

.glow-b {
  width: 360px;
  height: 360px;
  background: rgba(56, 132, 255, 0.22);
  bottom: -140px;
  left: -100px;
  animation: glow-float 11s ease-in-out infinite alternate-reverse;
}

@keyframes glow-float {
  to {
    transform: translate(40px, 30px) scale(1.12);
  }
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 820px;
}

.hero-kicker {
  display: inline-block;
  padding: 0.35rem 1rem;
  margin-bottom: 1.4rem;
  font-size: 0.85rem;
  letter-spacing: 0.2em;
  color: var(--accent);
  border: 1px solid rgba(0, 229, 168, 0.35);
  border-radius: 999px;
  background: rgba(0, 229, 168, 0.06);
}

.hero-title {
  font-size: clamp(2.2rem, 5.5vw, 4rem);
  font-weight: 800;
  line-height: 1.22;
  letter-spacing: 0.02em;
}

.accent-text {
  color: var(--accent);
}

.hero-sub {
  margin: 1.6rem 0 2.4rem;
  max-width: 40em;
  font-size: clamp(1rem, 1.4vw, 1.15rem);
  color: var(--text-muted);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.btn {
  display: inline-block;
  padding: 0.85rem 2.1rem;
  border-radius: 999px;
  font-size: 1rem;
  font-weight: 600;
  border: 1px solid transparent;
  transition: transform 0.25s var(--ease), box-shadow 0.25s var(--ease), background 0.25s var(--ease);
}

.btn:hover {
  transform: translateY(-2px);
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-deep));
  color: #04120c;
  box-shadow: 0 8px 28px rgba(0, 229, 168, 0.35);
}

.btn-primary:hover {
  box-shadow: 0 12px 36px rgba(0, 229, 168, 0.5);
}

.btn-ghost {
  border-color: rgba(232, 237, 245, 0.4);
  color: var(--text-dark);
}

.btn-ghost:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 2.5rem;
  margin-top: 3.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-dark);
}

.hero-stats strong {
  display: block;
  font-size: 2rem;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}

.hero-stats span {
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* ---------- 通用板块 ---------- */
.section {
  padding: clamp(4rem, 8vw, 6.5rem) 0;
}

.section-dark {
  background: var(--bg-dark);
  color: var(--text-dark);
}

.section-dim {
  background: var(--bg-dim);
  color: var(--text-dim);
}

.section-head {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 3.2rem;
}

.section-head.align-left {
  text-align: left;
  margin-inline: 0;
}

.section-kicker {
  font-size: 0.8rem;
  letter-spacing: 0.35em;
  color: var(--accent-deep);
  margin-bottom: 0.6rem;
}

.section-dim .section-kicker {
  color: var(--accent-deep);
}

.section-head h2 {
  font-size: clamp(1.7rem, 3.5vw, 2.4rem);
  letter-spacing: 0.04em;
}

.section-desc {
  margin-top: 0.9rem;
  color: var(--text-muted);
}

.section-dim .section-desc {
  color: #5b6675;
}

/* ---------- 核心技术卡片 ---------- */
.tech-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.4rem;
}

.tech-card {
  padding: 1.8rem;
  background: var(--bg-card);
  border: 1px solid var(--border-dark);
  border-radius: var(--radius);
  transition: transform 0.3s var(--ease), border-color 0.3s var(--ease);
}

.tech-card:hover {
  transform: translateY(-6px);
  border-color: rgba(0, 229, 168, 0.45);
}

.tech-icon {
  display: grid;
  place-items: center;
  width: 62px;
  height: 62px;
  margin-bottom: 1.2rem;
  color: var(--accent);
  background: rgba(0, 229, 168, 0.08);
  border: 1px solid rgba(0, 229, 168, 0.25);
  border-radius: 12px;
}

.tech-card h3 {
  font-size: 1.15rem;
  margin-bottom: 0.6rem;
}

.tech-card p {
  font-size: 0.92rem;
  color: var(--text-muted);
}

/* ---------- 产品中心 ---------- */
.product-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.4rem;
}

.product-card {
  display: flex;
  flex-direction: column;
  background: #fff;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 4px 20px rgba(16, 32, 56, 0.08);
  transition: transform 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.product-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 16px 40px rgba(16, 32, 56, 0.16);
}

/* 产品头图：纯 CSS 渐变 + 纹理占位，可替换为真实产品图 */
.product-visual {
  height: 170px;
  position: relative;
  overflow: hidden;
}

.product-visual::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
  background-size: 26px 26px;
}

.pv-a { background: linear-gradient(135deg, #0b111c 20%, #0f3d33 80%); }
.pv-b { background: linear-gradient(135deg, #101b30 20%, #123a5c 80%); }
.pv-c { background: linear-gradient(135deg, #141026 20%, #2c2456 80%); }
.pv-d { background: linear-gradient(135deg, #0d1f1a 20%, #1f4a3a 80%); }

/* 产品编号：大号半透明数字（参考 seauto 的 01/02/03/04 卡片编号） */
.product-num {
  position: absolute;
  left: 1rem;
  bottom: 0.4rem;
  font-size: 2.6rem;
  font-weight: 800;
  line-height: 1;
  color: rgba(255, 255, 255, 0.28);
  letter-spacing: 0.04em;
  z-index: 1;
}

.product-body {
  padding: 1.4rem;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
  flex: 1;
}

.product-tag {
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--accent-deep);
}

.product-body h3 {
  font-size: 1.2rem;
  color: #1b2734;
}

.product-body p {
  font-size: 0.9rem;
  color: #5b6675;
  flex: 1;
}

.link-more {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--accent-deep);
}

.link-more:hover span {
  transform: translateX(4px);
}

.link-more span {
  display: inline-block;
  transition: transform 0.25s var(--ease);
}

/* ---------- 解决方案 ---------- */
.solution-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.4rem;
}

.solution-card {
  padding: 1.8rem;
  background: linear-gradient(160deg, var(--bg-card), #0d1420);
  border: 1px solid var(--border-dark);
  border-radius: var(--radius);
  transition: transform 0.3s var(--ease), border-color 0.3s var(--ease);
}

.solution-card:hover {
  transform: translateY(-6px);
  border-color: rgba(0, 229, 168, 0.45);
}

.solution-card h3 {
  font-size: 1.15rem;
  margin-bottom: 0.6rem;
}

.solution-card p {
  font-size: 0.92rem;
  color: var(--text-muted);
  margin-bottom: 1.2rem;
}

.solution-meta {
  display: inline-block;
  padding: 0.25rem 0.9rem;
  font-size: 0.78rem;
  color: var(--accent);
  border: 1px solid rgba(0, 229, 168, 0.3);
  border-radius: 999px;
}

/* ---------- 新闻动态 ---------- */
.news-list {
  max-width: 900px;
  margin-inline: auto;
}

.news-item + .news-item {
  margin-top: 1.2rem;
}

.news-link {
  display: flex;
  align-items: center;
  gap: 1.6rem;
  padding: 1.4rem 1.8rem;
  background: #fff;
  border-radius: var(--radius);
  box-shadow: 0 4px 16px rgba(16, 32, 56, 0.07);
  transition: transform 0.3s var(--ease), box-shadow 0.3s var(--ease);
}

.news-link:hover {
  transform: translateY(-3px);
  box-shadow: 0 12px 32px rgba(16, 32, 56, 0.14);
}

.news-date {
  flex: none;
  width: 74px;
  text-align: center;
  color: #1b2734;
  line-height: 1.25;
}

.news-date b {
  display: block;
  font-size: 1.6rem;
}

.news-date span {
  font-size: 0.78rem;
  color: #8b95a5;
}

.news-body h3 {
  font-size: 1.05rem;
  color: #1b2734;
  margin-bottom: 0.35rem;
}

.news-body p {
  font-size: 0.88rem;
  color: #5b6675;
}

.news-arrow {
  flex: none;
  margin-left: auto;
  color: var(--accent-deep);
  transition: transform 0.25s var(--ease);
}

.news-link:hover .news-arrow {
  transform: translateX(6px);
}

/* ---------- 关于我们 ---------- */
.about-inner {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 3.5rem;
  align-items: center;
}

.about-text > p {
  color: var(--text-muted);
  margin-bottom: 1rem;
}

.about-facts {
  margin-top: 1.6rem;
  display: grid;
  gap: 0.9rem;
}

.about-facts li {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 1rem;
  align-items: baseline;
}

.about-facts strong {
  color: var(--accent);
}

.about-facts span {
  color: var(--text-muted);
}

/* 品牌视觉卡：纯 CSS 占位，可替换为形象图 */
.about-visual {
  display: grid;
  place-items: center;
}

.about-card {
  display: grid;
  gap: 0.4rem;
  justify-items: center;
  padding: 3.5rem 3rem;
  width: 100%;
  max-width: 380px;
  border-radius: 20px;
  background:
    radial-gradient(circle at 30% 20%, rgba(0, 229, 168, 0.18), transparent 55%),
    var(--bg-card);
  border: 1px solid var(--border-dark);
  box-shadow: var(--shadow);
}

.about-card-kicker {
  font-size: 0.7rem;
  letter-spacing: 0.4em;
  color: var(--accent);
}

.about-card-title {
  font-size: 2.4rem;
  font-weight: 800;
  color: #fff;
}

.about-card-sub {
  font-size: 0.8rem;
  color: var(--text-muted);
  letter-spacing: 0.12em;
}

/* ---------- 联系我们 ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.4rem;
}

.contact-card {
  padding: 1.8rem;
  background: #fff;
  border-radius: var(--radius);
  box-shadow: 0 4px 16px rgba(16, 32, 56, 0.07);
}

.contact-card h3 {
  font-size: 1.1rem;
  color: #1b2734;
  margin-bottom: 0.9rem;
  padding-bottom: 0.7rem;
  border-bottom: 2px solid var(--accent);
  display: inline-block;
}

.contact-card p {
  font-size: 0.92rem;
  color: #5b6675;
  margin-bottom: 0.4rem;
}

.contact-label {
  display: inline-block;
  min-width: 3.5em;
  color: #8b95a5;
}

.contact-card a {
  color: var(--accent-deep);
}

.contact-card a:hover {
  text-decoration: underline;
}

/* ---------- 在线留言表单 ---------- */
.contact-form {
  margin-top: 1.6rem;
  padding: 2.2rem clamp(1.4rem, 3vw, 2.4rem);
  background: #fff;
  border-radius: var(--radius);
  box-shadow: 0 4px 20px rgba(16, 32, 56, 0.08);
}

.contact-form h3 {
  font-size: 1.35rem;
  color: #1b2734;
}

.form-desc {
  margin: 0.5rem 0 1.6rem;
  font-size: 0.9rem;
  color: #5b6675;
}

.form-desc b,
.form-field label b {
  color: #e5484d;
}

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.1rem 1.4rem;
}

.form-field {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.form-field-wide {
  grid-column: 1 / -1;
}

.form-field label {
  font-size: 0.88rem;
  font-weight: 600;
  color: #33404f;
}

.form-field input,
.form-field textarea {
  width: 100%;
  padding: 0.75rem 0.95rem;
  font: inherit;
  font-size: 0.92rem;
  color: #1b2734;
  background: #f5f7fa;
  border: 1px solid #d5dbe4;
  border-radius: 10px;
  transition: border-color 0.25s var(--ease), box-shadow 0.25s var(--ease);
}

.form-field textarea {
  resize: vertical;
  min-height: 120px;
}

.form-field input:focus,
.form-field textarea:focus {
  outline: none;
  border-color: var(--accent-deep);
  box-shadow: 0 0 0 3px rgba(0, 179, 131, 0.15);
}

/* 校验不通过时 JS 添加 is-invalid */
.form-field.is-invalid input,
.form-field.is-invalid textarea {
  border-color: #e5484d;
  box-shadow: 0 0 0 3px rgba(229, 72, 77, 0.12);
}

.form-field .field-error {
  font-size: 0.8rem;
  color: #e5484d;
}

.form-status {
  margin: 1.1rem 0 0;
  font-size: 0.9rem;
  min-height: 1.4em;
}

.form-status.is-success {
  color: #0a8a5f;
}

.form-status.is-error {
  color: #e5484d;
}

.form-submit {
  margin-top: 0.9rem;
  border: 0;
  cursor: pointer;
  font-family: inherit;
}

.form-submit:hover {
  transform: translateY(-2px);
}

.form-note {
  margin-top: 1rem;
  font-size: 0.78rem;
  color: #8b95a5;
}

/* ---------- 页脚 ---------- */
.site-footer {
  background: #070b13;
  border-top: 1px solid var(--border-dark);
  padding: 3.5rem 0 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 2.5rem;
  padding-bottom: 3rem;
}

.footer-logo {
  font-size: 1.4rem;
  font-weight: 800;
  color: #fff;
}

.footer-logo em {
  font-style: normal;
  font-size: 0.8rem;
  letter-spacing: 0.3em;
  color: var(--accent);
  margin-left: 0.5rem;
}

.footer-slogan {
  margin-top: 0.8rem;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.footer-col h3 {
  font-size: 0.95rem;
  color: #fff;
  margin-bottom: 1rem;
}

.footer-col ul {
  display: grid;
  gap: 0.55rem;
}

.footer-col a,
.footer-col li {
  font-size: 0.88rem;
  color: var(--text-muted);
}

.footer-col a:hover {
  color: var(--accent);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.6rem;
  padding: 1.4rem 0;
  border-top: 1px solid var(--border-dark);
  font-size: 0.8rem;
  color: var(--text-muted);
}

.footer-bottom a:hover {
  color: var(--accent);
}

/* ---------- 入场动画（JS 触发 .is-visible） ---------- */
.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}

.reveal.is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 响应式：平板 ---------- */
@media (max-width: 1024px) {
  .tech-grid,
  .solution-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .product-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .about-inner {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }
}

/* ---------- 响应式：手机 ---------- */
@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  /* 移动端抽屉式导航 */
  .primary-nav {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    background: rgba(9, 14, 24, 0.98);
    border-bottom: 1px solid var(--border-dark);
    transform: translateY(-110%);
    visibility: hidden;
    transition: transform 0.35s var(--ease), visibility 0.35s;
  }

  .primary-nav.is-open {
    transform: none;
    visibility: visible;
  }

  .primary-nav > ul {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 0.8rem 1.4rem 1.4rem;
  }

  .primary-nav > ul > li > a {
    display: block;
    padding: 0.85rem 0;
    border-bottom: 1px solid var(--border-dark);
  }

  .primary-nav a::after {
    display: none;
  }

  .hero {
    min-height: 92dvh;
  }

  .hero-stats {
    gap: 1.6rem;
  }

  .news-link {
    flex-wrap: wrap;
    gap: 0.9rem;
  }

  .news-arrow {
    display: none;
  }

  /* 移动端：抽屉内嵌式语言菜单（默认展开） */
  .lang-trigger {
    width: 100%;
    justify-content: space-between;
    padding: 0.85rem 0;
    border-bottom: 1px solid var(--border-dark);
  }
  .lang-trigger[aria-expanded="true"] .lang-caret {
    transform: none; /* 移动端下拉常驻可见，箭头不旋转 */
  }
  .lang-dropdown {
    position: static;
    display: block;
    opacity: 1;
    visibility: visible;
    transform: none;
    background: transparent;
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    border: 0;
    border-radius: 0;
    box-shadow: none;
    padding: 0 0 0.6rem 0.9rem;
    min-width: 0;
    transition: none;
  }
  .lang-menu.is-open .lang-dropdown {
    transition: none;
    transform: none;
  }
  .lang-dropdown a {
    padding: 0.55rem 0.8rem;
    font-size: 0.88rem;
    color: rgba(232, 237, 245, 0.7);
  }
  .lang-dropdown a[aria-current="page"] {
    background: transparent;
    color: var(--accent);
  }
}

/* ---------- 响应式：小屏手机 ---------- */
@media (max-width: 480px) {
  .tech-grid,
  .solution-grid,
  .product-grid,
  .contact-grid,
  .form-grid {
    grid-template-columns: 1fr;
  }

  .hero-actions .btn {
    width: 100%;
    text-align: center;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 1.8rem;
  }

  .footer-bottom {
    flex-direction: column;
  }
}

/* ---------- 减少动态效果（尊重用户系统设置） ---------- */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}