/* ==========================================================================
   小比智能科技 · 站点样式层（导航 / 首屏 / 板块 / 页脚 / 页面专有）
   ========================================================================== */

/* ============================  顶部导航  ============================ */

.nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  height: 72px;
  display: flex;
  align-items: center;
  transition: background 0.4s var(--ease), border-color 0.4s var(--ease),
    backdrop-filter 0.4s var(--ease);
  border-bottom: 1px solid transparent;
}

.nav.is-scrolled {
  background: rgba(5, 6, 10, 0.72);
  backdrop-filter: saturate(160%) blur(18px);
  -webkit-backdrop-filter: saturate(160%) blur(18px);
  border-bottom-color: var(--line);
}

.nav__inner {
  display: flex;
  align-items: center;
  gap: 40px;
  width: 100%;
}

/* 品牌 */
.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  flex: none;
}

.brand__mark {
  width: 26px;
  height: 26px;
  flex: none;
}

.brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1;
}

.brand__cn {
  font-size: 0.9375rem;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.brand__en {
  font-family: var(--font-mono);
  font-size: 0.5625rem;
  letter-spacing: 0.18em;
  color: var(--text-3);
  margin-top: 4px;
  text-transform: uppercase;
}

/* 主导航链接 */
.nav__links {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-left: auto;
}

.nav__link {
  position: relative;
  padding: 8px 14px;
  font-size: 0.875rem;
  color: var(--text-2);
  border-radius: 99px;
  transition: color 0.3s var(--ease), background 0.3s var(--ease);
}

.nav__link:hover {
  color: var(--text);
  background: rgba(255, 255, 255, 0.05);
}

.nav__link.is-active {
  color: var(--text);
}

.nav__link.is-active::after {
  content: "";
  position: absolute;
  left: 50%;
  bottom: 1px;
  width: 4px;
  height: 4px;
  margin-left: -2px;
  border-radius: 50%;
  background: var(--brand);
  box-shadow: 0 0 8px var(--brand);
}

.nav__right {
  display: flex;
  align-items: center;
  gap: 14px;
  flex: none;
}

/* 语言切换 */
.lang {
  display: flex;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.08em;
  border: 1px solid var(--line);
  border-radius: 99px;
  padding: 3px;
  gap: 2px;
}

.lang__btn {
  padding: 4px 9px;
  border-radius: 99px;
  color: var(--text-3);
  transition: color 0.25s var(--ease), background 0.25s var(--ease);
}

.lang__btn:hover {
  color: var(--text);
}

.lang__btn.is-on {
  color: #05060a;
  background: var(--text);
}

.nav .btn {
  height: 38px;
  padding-inline: 18px;
  font-size: 0.8125rem;
}

/* 移动端汉堡 */
.nav__burger {
  display: none;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line);
  border-radius: 99px;
}

.nav__burger span {
  position: relative;
  width: 16px;
  height: 1px;
  background: var(--text);
  transition: transform 0.3s var(--ease), opacity 0.3s var(--ease);
}

.nav__burger span::before,
.nav__burger span::after {
  content: "";
  position: absolute;
  left: 0;
  width: 16px;
  height: 1px;
  background: var(--text);
  transition: transform 0.3s var(--ease);
}

.nav__burger span::before {
  top: -5px;
}
.nav__burger span::after {
  top: 5px;
}

body.menu-open .nav__burger span {
  background: transparent;
}
body.menu-open .nav__burger span::before {
  transform: translateY(5px) rotate(45deg);
}
body.menu-open .nav__burger span::after {
  transform: translateY(-5px) rotate(-45deg);
}

/* 移动端抽屉 */
.drawer {
  position: fixed;
  inset: 72px 0 0 0;
  z-index: 99;
  background: rgba(5, 6, 10, 0.98);
  backdrop-filter: blur(20px);
  padding: 32px var(--gutter) 48px;
  display: flex;
  flex-direction: column;
  gap: 2px;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-8px);
  transition: opacity 0.35s var(--ease), transform 0.35s var(--ease),
    visibility 0.35s;
}

body.menu-open .drawer {
  opacity: 1;
  visibility: visible;
  transform: none;
}

.drawer a {
  padding: 18px 0;
  font-size: 1.25rem;
  border-bottom: 1px solid var(--line);
  color: var(--text-2);
}

.drawer a.is-active {
  color: var(--text);
}

.drawer .btn {
  margin-top: 28px;
  height: 50px;
  width: 100%;
  color: #05060a;
}

/* ============================  首屏  ============================ */

.hero {
  position: relative;
  min-height: 100svh;
  display: flex;
  align-items: center;
  padding-top: 140px;
  padding-bottom: 90px;
  overflow: hidden;
  isolation: isolate;
}

/* Canvas 点云层 */
.hero__canvas,
.page-hero__canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: -2;
  opacity: 0.85;
}

/* 背景光晕 */
.hero::before {
  content: "";
  position: absolute;
  z-index: -3;
  left: 50%;
  top: -30%;
  width: 1200px;
  height: 900px;
  transform: translateX(-50%);
  background: radial-gradient(
    ellipse at center,
    rgba(79, 124, 255, 0.22) 0%,
    rgba(124, 92, 255, 0.1) 38%,
    transparent 68%
  );
  filter: blur(20px);
  pointer-events: none;
}

/* 底部渐隐，融合下一页 */
.hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 220px;
  z-index: -1;
  background: linear-gradient(to bottom, transparent, var(--bg));
  pointer-events: none;
}

.hero__inner {
  position: relative;
  width: 100%;
}

.hero__eyebrow {
  margin-bottom: 30px;
}

.hero__title {
  max-width: 12em;
  margin-bottom: 32px;
}

.hero__sub {
  max-width: 36em;
  font-size: clamp(1rem, 1.3vw, 1.1875rem);
  line-height: 1.7;
  color: var(--text-2);
  margin-bottom: 44px;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}

/* 首屏底部数据条 */
.hero__meta {
  position: relative;
  margin-top: 96px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.hero__meta-item {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.hero__meta-num {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 500;
  letter-spacing: -0.02em;
  color: var(--text);
}

.hero__meta-label {
  font-size: 0.75rem;
  color: var(--text-3);
  letter-spacing: 0.02em;
}

/* 滚动提示 */
.scroll-hint {
  position: absolute;
  bottom: 28px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 0.5625rem;
  letter-spacing: 0.22em;
  color: var(--text-3);
  text-transform: uppercase;
  z-index: 2;
}

.scroll-hint__line {
  width: 1px;
  height: 38px;
  background: linear-gradient(to bottom, var(--text-3), transparent);
  overflow: hidden;
  position: relative;
}

.scroll-hint__line::after {
  content: "";
  position: absolute;
  top: -38px;
  left: 0;
  width: 1px;
  height: 38px;
  background: linear-gradient(to bottom, transparent, var(--brand));
  animation: scrollLine 2.2s var(--ease) infinite;
}

@keyframes scrollLine {
  0% {
    top: -38px;
  }
  60%,
  100% {
    top: 38px;
  }
}

/* ============================  滚动关键词条  ============================ */

.marquee {
  position: relative;
  padding-block: 22px;
  border-block: 1px solid var(--line);
  overflow: hidden;
  background: rgba(255, 255, 255, 0.012);
  mask-image: linear-gradient(90deg, transparent, #000 8%, #000 92%, transparent);
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 8%, #000 92%, transparent);
}

.marquee__track {
  display: flex;
  width: max-content;
  gap: 56px;
  animation: marquee 42s linear infinite;
}

.marquee:hover .marquee__track {
  animation-play-state: paused;
}

.marquee__item {
  display: inline-flex;
  align-items: center;
  gap: 56px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-3);
  white-space: nowrap;
}

.marquee__item::after {
  content: "";
  width: 4px;
  height: 4px;
  background: var(--line-3);
  border-radius: 50%;
}

@keyframes marquee {
  to {
    transform: translateX(-50%);
  }
}

/* ============================  双业务线  ============================ */

.biz {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.biz__card {
  position: relative;
  display: flex;
  flex-direction: column;
  min-height: 520px;
  padding: 40px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--bg-1);
  transition: border-color 0.45s var(--ease), transform 0.45s var(--ease);
}

.biz__card:hover {
  border-color: var(--line-2);
  transform: translateY(-3px);
}

/* 卡片顶部光带 */
.biz__card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 10%;
  right: 10%;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--brand), transparent);
  opacity: 0.55;
  transition: opacity 0.45s var(--ease), left 0.6s var(--ease),
    right 0.6s var(--ease);
}

.biz__card:hover::before {
  opacity: 1;
  left: 0;
  right: 0;
}

/* 卡片内的大号编号水印 */
.biz__card::after {
  content: attr(data-index);
  position: absolute;
  right: 26px;
  top: 6px;
  font-family: var(--font-mono);
  font-size: 9rem;
  font-weight: 600;
  line-height: 1;
  letter-spacing: -0.04em;
  color: rgba(255, 255, 255, 0.028);
  pointer-events: none;
}

.biz__head {
  position: relative;
  z-index: 1;
  margin-bottom: auto;
}

.biz__tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 26px;
  padding-inline: 11px;
  margin-bottom: 26px;
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-2);
  border: 1px solid var(--line-2);
  border-radius: 99px;
}

.biz__tag i {
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--c, var(--brand));
  box-shadow: 0 0 8px var(--c, var(--brand));
}

.biz__title {
  font-size: clamp(1.6rem, 2.4vw, 2.1rem);
  letter-spacing: -0.03em;
  margin-bottom: 8px;
}

.biz__title-en {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: 22px;
}

.biz__desc {
  font-size: 0.9375rem;
  line-height: 1.75;
  color: var(--text-2);
  max-width: 30em;
}

/* 卡片内的关键指标 */
.biz__metrics {
  display: flex;
  gap: 46px;
  margin-top: 36px;
  padding-top: 26px;
  border-top: 1px solid var(--line);
}

.biz__metric b {
  display: block;
  font-family: var(--font-mono);
  font-size: 1.125rem;
  font-weight: 500;
  letter-spacing: -0.02em;
  color: var(--text);
  margin-bottom: 5px;
  white-space: nowrap;
}

.biz__metric span {
  font-size: 0.6875rem;
  letter-spacing: 0.02em;
  color: var(--text-3);
}

.biz__foot {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  gap: 22px;
  margin-top: 40px;
  padding-top: 26px;
  border-top: 1px solid var(--line);
}

.biz__points {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.chip {
  display: inline-flex;
  align-items: center;
  height: 26px;
  padding-inline: 11px;
  font-size: 0.75rem;
  color: var(--text-2);
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--line);
  border-radius: 99px;
  white-space: nowrap;
}

/* 卡片背景的抽象图形 */
.biz__art {
  position: absolute;
  right: -60px;
  bottom: -60px;
  width: 320px;
  height: 320px;
  opacity: 0.5;
  pointer-events: none;
  z-index: 0;
}

/* ============================  三层引擎 / 能力分层  ============================ */

.layers {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.layer {
  position: relative;
  padding: 48px 44px;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.008);
  transition: background 0.45s var(--ease);
}

.layer:hover {
  background: rgba(79, 124, 255, 0.035);
}

.layer:nth-child(odd) {
  border-right: 1px solid var(--line);
}

.layer:nth-last-child(-n + 2) {
  border-bottom: 0;
}

.layer__idx {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  color: var(--text-3);
  margin-bottom: 30px;
  display: block;
}

.layer__title {
  font-size: 1.375rem;
  letter-spacing: -0.02em;
  margin-bottom: 14px;
}

.layer__desc {
  font-size: 0.9375rem;
  line-height: 1.72;
  color: var(--text-2);
  max-width: 46ch;
}

.layer__icon {
  position: absolute;
  top: 44px;
  right: 40px;
  width: 34px;
  height: 34px;
  color: var(--text-3);
  opacity: 0.6;
  transition: color 0.4s var(--ease), opacity 0.4s var(--ease);
}

.layer:hover .layer__icon {
  color: var(--brand);
  opacity: 1;
}

/* ============================  流程步骤  ============================ */

.flow {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0;
  counter-reset: step;
}

.flow__step {
  position: relative;
  padding: 34px 26px 34px 0;
  border-top: 1px solid var(--line-2);
}

.flow__step::before {
  content: "";
  position: absolute;
  top: -2.5px;
  left: 0;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--brand);
  box-shadow: 0 0 10px var(--brand);
}

.flow__num {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.14em;
  color: var(--brand);
  margin-bottom: 16px;
}

.flow__title {
  font-size: 1rem;
  font-weight: 500;
  margin-bottom: 10px;
}

.flow__desc {
  font-size: 0.8125rem;
  line-height: 1.65;
  color: var(--text-3);
}

.flow--4 {
  grid-template-columns: repeat(4, 1fr);
}

@media (max-width: 900px) {
  .flow--4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 560px) {
  .flow--4 {
    grid-template-columns: 1fr;
  }
}

/* ============================  数据面板  ============================ */

.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: linear-gradient(180deg, rgba(79, 124, 255, 0.05), transparent 60%);
}

.stat {
  padding: 40px 32px;
  border-right: 1px solid var(--line);
  transition: background 0.4s var(--ease);
}

.stat:last-child {
  border-right: 0;
}

.stat:hover {
  background: rgba(255, 255, 255, 0.022);
}

.stat__num {
  display: flex;
  align-items: baseline;
  gap: 3px;
  font-family: var(--font-mono);
  font-size: clamp(2rem, 3.4vw, 2.9rem);
  font-weight: 500;
  letter-spacing: -0.035em;
  line-height: 1;
  margin-bottom: 14px;
  color: var(--text);
}

.stat__num sup {
  font-size: 0.42em;
  color: var(--brand);
  font-weight: 400;
  top: -0.75em;
}

.stat__label {
  font-size: 0.8125rem;
  color: var(--text-3);
  line-height: 1.5;
}

/* ============================  通用 CTA 区  ============================ */

.cta {
  position: relative;
  padding-block: 120px;
  overflow: hidden;
  border-top: 1px solid var(--line);
  text-align: center;
}

.cta::before {
  content: "";
  position: absolute;
  left: 50%;
  bottom: -40%;
  width: 1000px;
  height: 600px;
  transform: translateX(-50%);
  background: radial-gradient(
    ellipse at center,
    rgba(79, 124, 255, 0.2),
    transparent 66%
  );
  pointer-events: none;
}

.cta__inner {
  position: relative;
  max-width: 720px;
  margin-inline: auto;
}

.cta__title {
  margin-bottom: 22px;
}

.cta__sub {
  color: var(--text-2);
  margin-bottom: 40px;
  font-size: 1.0625rem;
}

.cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

/* ============================  页脚  ============================ */

.footer {
  border-top: 1px solid var(--line);
  padding-top: 72px;
  padding-bottom: 40px;
  background: var(--bg);
}

.footer__top {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 48px;
  padding-bottom: 64px;
}

.footer__brand .brand {
  margin-bottom: 20px;
}

.footer__about {
  font-size: 0.8125rem;
  line-height: 1.75;
  color: var(--text-3);
  max-width: 34ch;
}

.footer__col h5 {
  font-family: var(--font-mono);
  font-size: 0.625rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-3);
  margin-bottom: 18px;
  font-weight: 500;
}

.footer__col ul {
  display: flex;
  flex-direction: column;
  gap: 11px;
}

.footer__col a,
.footer__col li {
  font-size: 0.8125rem;
  color: var(--text-2);
  transition: color 0.25s var(--ease);
}

.footer__col a:hover {
  color: var(--text);
}

.footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
  font-size: 0.75rem;
  color: var(--text-3);
}

.footer__legal {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
}

/* ============================  内页 Hero  ============================ */

.page-hero {
  position: relative;
  padding-top: 180px;
  padding-bottom: 96px;
  overflow: hidden;
  isolation: isolate;
  border-bottom: 1px solid var(--line);
}

.page-hero::before {
  content: "";
  position: absolute;
  z-index: -3;
  left: 50%;
  top: -45%;
  width: 1100px;
  height: 780px;
  transform: translateX(-50%);
  background: radial-gradient(
    ellipse at center,
    rgba(79, 124, 255, 0.2),
    transparent 68%
  );
  pointer-events: none;
}

.page-hero__eyebrow {
  margin-bottom: 26px;
}

.page-hero__title {
  max-width: 12em;
  margin-bottom: 26px;
}

.page-hero__sub {
  max-width: 38em;
  font-size: clamp(1rem, 1.25vw, 1.125rem);
  line-height: 1.75;
  color: var(--text-2);
  margin-bottom: 40px;
}

/* 内页面包屑 */
.crumb {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  color: var(--text-3);
  margin-bottom: 34px;
  text-transform: uppercase;
}

.crumb a:hover {
  color: var(--text);
}

.crumb span {
  opacity: 0.5;
}

/* ============================  内容块通用  ============================ */

/* 两栏：左标题 右内容 */
.split {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: 80px;
  align-items: start;
}

.split__sticky {
  position: sticky;
  top: 110px;
}

.split__body p + p {
  margin-top: 18px;
}

.split__body .t-body {
  margin-bottom: 0;
}

/* 三列特性 */
.features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.feature {
  padding: 38px 32px;
  background: var(--bg);
  transition: background 0.4s var(--ease);
}

.feature:hover {
  background: var(--bg-2);
}

.feature__icon {
  width: 26px;
  height: 26px;
  color: var(--brand);
  margin-bottom: 26px;
}

.feature__title {
  font-size: 1rem;
  font-weight: 500;
  margin-bottom: 12px;
}

.feature__desc {
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--text-3);
}

/* 场景列表 */
.scenes {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.scene {
  position: relative;
  padding: 32px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--bg-1);
  transition: border-color 0.4s var(--ease), transform 0.4s var(--ease);
}

.scene:hover {
  border-color: var(--line-2);
  transform: translateY(-2px);
}

.scene__num {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-3);
  letter-spacing: 0.12em;
  display: block;
  margin-bottom: 24px;
}

.scene__title {
  font-size: 1.0625rem;
  font-weight: 500;
  margin-bottom: 10px;
}

.scene__desc {
  font-size: 0.8125rem;
  line-height: 1.7;
  color: var(--text-3);
}

/* 规格表 */
.spec-table {
  width: 100%;
  border-collapse: collapse;
  border-top: 1px solid var(--line-2);
}

.spec-table th,
.spec-table td {
  padding: 18px 0;
  text-align: left;
  border-bottom: 1px solid var(--line);
  font-size: 0.875rem;
  vertical-align: top;
}

.spec-table th {
  width: 30%;
  font-weight: 400;
  color: var(--text-3);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  padding-right: 24px;
}

.spec-table td {
  color: var(--text-2);
}

.spec-table tr:hover td {
  color: var(--text);
}

/* 编号列表（关于页价值观） */
.vlist {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.vlist__item {
  display: flex;
  gap: 22px;
  padding: 34px 32px;
  background: var(--bg);
}

.vlist__num {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--brand);
  letter-spacing: 0.1em;
  padding-top: 4px;
  flex: none;
}

.vlist__title {
  font-size: 1rem;
  font-weight: 500;
  margin-bottom: 8px;
}

.vlist__desc {
  font-size: 0.8125rem;
  line-height: 1.7;
  color: var(--text-3);
}

/* ============================  响应式  ============================ */

@media (max-width: 1080px) {
  .nav__links {
    display: none;
  }
  .nav__burger {
    display: flex;
  }
  .nav__inner {
    gap: 16px;
  }
  .nav__right {
    margin-left: auto;
  }
  .split {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .split__sticky {
    position: static;
  }
  .footer__top {
    grid-template-columns: 1fr 1fr;
    gap: 40px;
  }
  .flow {
    grid-template-columns: repeat(2, 1fr);
  }
  .stats {
    grid-template-columns: repeat(2, 1fr);
  }
  .stat:nth-child(2) {
    border-right: 0;
  }
  .stat:nth-child(-n + 2) {
    border-bottom: 1px solid var(--line);
  }
}

@media (max-width: 900px) {
  .biz {
    grid-template-columns: 1fr;
  }
  .biz__card {
    min-height: auto;
    padding: 32px 26px;
  }
  .biz__head {
    margin-bottom: 16px;
  }
  .layers {
    grid-template-columns: 1fr;
  }
  .layer:nth-child(odd) {
    border-right: 0;
  }
  .layer:nth-last-child(-n + 2) {
    border-bottom: 1px solid var(--line);
  }
  .layer:last-child {
    border-bottom: 0;
  }
  .layer {
    padding: 34px 26px;
  }
  .layer__icon {
    top: 32px;
    right: 24px;
    width: 26px;
    height: 26px;
  }
  .features,
  .scenes,
  .vlist {
    grid-template-columns: 1fr;
  }
  .hero__meta {
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    margin-top: 64px;
  }
  .hero {
    padding-top: 120px;
    min-height: auto;
  }
  .page-hero {
    padding-top: 130px;
    padding-bottom: 64px;
  }
  .scroll-hint {
    display: none;
  }
  .cta {
    padding-block: 84px;
  }
  .footer__top {
    grid-template-columns: 1fr;
    gap: 36px;
    padding-bottom: 44px;
  }
  .footer__bottom {
    flex-direction: column;
    align-items: flex-start;
  }
  .section--tight {
    padding-block: 64px;
  }
}

/* ============================  采集管线示意图  ============================ */

.pipeline {
  padding: 44px 40px 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(180deg, rgba(79, 124, 255, 0.045), rgba(255, 255, 255, 0.008));
}

.pipeline__svg {
  width: 100%;
  height: auto;
  overflow: visible;
}

.pipeline__idx {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  fill: var(--brand);
}

.pipeline__label {
  font-family: var(--font-sans);
  font-size: 14.5px;
  font-weight: 500;
  fill: var(--text);
  letter-spacing: 0.01em;
}

.pipeline__sub {
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.13em;
  fill: var(--text-3);
}

.pipeline__note {
  font-family: var(--font-mono);
  font-size: 9.5px;
  letter-spacing: 0.1em;
  fill: var(--text-3);
  opacity: 0.8;
}

/* 流动的虚线：模拟数据在管线里推进 */
.pipeline__flow {
  animation: dashFlow 2.6s linear infinite;
}

@keyframes dashFlow {
  to {
    stroke-dashoffset: -30;
  }
}

.pipeline__list {
  display: none;
}

/* ============================  两列特性网格  ============================ */

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

/* 两列布局下每栏更宽，限制正文行宽保证可读性 */
.features--2col .feature {
  padding: 40px 38px;
}

.features--2col .feature__desc {
  max-width: 26em;
}

@media (max-width: 760px) {
  .pipeline {
    padding: 26px 22px 18px;
  }
  .pipeline__svg {
    display: none;
  }
  .pipeline__list {
    display: grid;
    gap: 1px;
    background: var(--line);
  }
  .pipeline__list div {
    display: flex;
    gap: 14px;
    padding: 16px 0;
    background: transparent;
    font-size: 0.8125rem;
    color: var(--text-2);
    border-bottom: 1px solid var(--line);
  }
  .pipeline__list div:last-child {
    border-bottom: 0;
  }
  .pipeline__list b {
    font-family: var(--font-mono);
    font-size: 0.6875rem;
    color: var(--brand);
    font-weight: 400;
    flex: none;
  }
  .features--2col {
    grid-template-columns: 1fr;
  }
}

/* ============================  表单  ============================ */

.form {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 22px;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.field--full {
  grid-column: 1 / -1;
}

.field label {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-3);
}

.field input,
.field select,
.field textarea {
  width: 100%;
  padding: 13px 0;
  font-family: inherit;
  font-size: 0.9375rem;
  color: var(--text);
  background: transparent;
  border: 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 0;
  outline: none;
  transition: border-color 0.3s var(--ease);
  appearance: none;
  -webkit-appearance: none;
}

.field textarea {
  min-height: 96px;
  resize: vertical;
  line-height: 1.6;
}

.field select {
  cursor: pointer;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath d='M2.5 4.5L6 8l3.5-3.5' stroke='%236b7488' stroke-width='1.3' fill='none' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 2px center;
  padding-right: 24px;
}

.field select option {
  background: var(--bg-2);
  color: var(--text);
}

.field input::placeholder,
.field textarea::placeholder {
  color: var(--text-3);
  opacity: 0.75;
}

.field input:focus,
.field select:focus,
.field textarea:focus {
  border-bottom-color: var(--brand);
}

.field input:focus-visible,
.field select:focus-visible,
.field textarea:focus-visible {
  box-shadow: 0 1px 0 0 var(--brand);
}

.form__foot {
  grid-column: 1 / -1;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  margin-top: 12px;
}

.form__note {
  font-size: 0.75rem;
  color: var(--text-3);
  max-width: 34ch;
  line-height: 1.6;
}

.form__msg {
  grid-column: 1 / -1;
  font-size: 0.875rem;
  color: var(--text-2);
  padding: 14px 18px;
  border: 1px solid var(--line-2);
  border-radius: var(--radius);
  background: rgba(79, 124, 255, 0.07);
  display: none;
}

.form__msg.is-on {
  display: block;
}

/* 联系方式页：两栏 */
.contact-grid {
  display: grid;
  grid-template-columns: 1.35fr 1fr;
  gap: 90px;
  align-items: start;
}

.contact-callout {
  margin-top: 34px;
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: linear-gradient(180deg, rgba(79, 124, 255, 0.06), rgba(255, 255, 255, 0.01));
}

.contact-callout .eyebrow {
  display: flex;
}

@media (max-width: 900px) {
  .contact-grid {
    grid-template-columns: 1fr;
    gap: 60px;
  }
}

/* 联系信息块 */
.contact-info {
  display: flex;
  flex-direction: column;
  gap: 0;
  border-top: 1px solid var(--line-2);
}

.contact-info__row {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 20px;
  padding: 20px 0;
  border-bottom: 1px solid var(--line);
  font-size: 0.875rem;
}

.contact-info__row dt {
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-3);
  padding-top: 2px;
}

.contact-info__row dd {
  color: var(--text);
}

.contact-info__row dd a:hover {
  color: var(--brand);
}

@media (max-width: 760px) {
  .form {
    grid-template-columns: 1fr;
  }
  .contact-info__row {
    grid-template-columns: 1fr;
    gap: 6px;
  }
}

@media (max-width: 560px) {
  .brand__en {
    display: none;
  }
  .nav .btn {
    display: none;
  }
  .hero__actions .btn,
  .cta__actions .btn {
    width: 100%;
  }
  .flow {
    grid-template-columns: 1fr;
  }
  .stats {
    grid-template-columns: 1fr;
  }
  .stat {
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }
  .stat:last-child {
    border-bottom: 0;
  }
  .marquee__item {
    gap: 32px;
  }
  .marquee__track {
    gap: 32px;
  }
}