/* OT Code 官网 —— 大字、留白、深浅交替、滚动叙事。不依赖外部字体和 CDN（国内访问稳定） */
:root {
  --bg: #000;
  --fg: #f5f5f7;
  --muted: #a1a1a6;
  --dim: #6e6e73;
  --line: rgba(255, 255, 255, 0.1);
  --card: #111214;
  --card-2: #18191c;
  --light: #f5f5f7;
  --light-fg: #1d1d1f;
  --light-muted: #6e6e73;
  --teal: #2dd4bf;
  --teal-d: #0d9488;
  --cyan: #22d3ee;
  --ok: #34d399;
  --warn: #fbbf24;
  --bad: #f87171;
  --grad: linear-gradient(90deg, #5eead4 0%, #2dd4bf 45%, #22d3ee 100%);
  --font: -apple-system, BlinkMacSystemFont, 'SF Pro SC', 'SF Pro Display', 'PingFang SC', 'HarmonyOS Sans SC', 'MiSans', 'Microsoft YaHei', 'Noto Sans SC', 'Helvetica Neue', sans-serif;
  --mono: 'SF Mono', 'JetBrains Mono', 'Cascadia Code', Consolas, 'Courier New', monospace;
  --ease: cubic-bezier(0.25, 0.1, 0.25, 1);
  --nav-h: 52px;
  /* 区块上下留白：区块高度随内容，留白统一用这个值（平板、手机逐级减小） */
  --sec: 104px;
}

* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}
a {
  color: inherit;
  text-decoration: none;
}
[hidden] {
  display: none !important;
}
section[id] {
  scroll-margin-top: var(--nav-h);
}
.wrap {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 22px;
}

/* ───── 导航 ───── */
.nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 50;
  height: var(--nav-h);
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.3s var(--ease), background 0.3s var(--ease);
}
.nav.scrolled {
  border-bottom-color: var(--line);
  background: rgba(10, 10, 12, 0.72);
}
.nav-inner {
  max-width: 1120px;
  height: 100%;
  margin: 0 auto;
  padding: 0 22px;
  display: flex;
  align-items: center;
  gap: 28px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 9px;
  font-weight: 600;
  font-size: 16px;
  letter-spacing: -0.01em;
}
.logo {
  width: 24px;
  height: 24px;
  flex-shrink: 0;
}
.nav-links {
  display: flex;
  gap: 28px;
  margin-left: auto;
  font-size: 13px;
  color: rgba(245, 245, 247, 0.8);
}
.nav-links a {
  transition: color 0.2s;
}
.nav-links a:hover {
  color: #fff;
}
.nav-contact {
  font-size: 13px;
  color: rgba(245, 245, 247, 0.8);
  transition: color 0.2s;
}
.nav-contact:hover {
  color: #fff;
}
.nav-cta {
  font-size: 13px;
  padding: 5px 14px;
  border-radius: 980px;
  background: var(--teal);
  color: #031512;
  font-weight: 600;
  transition: transform 0.2s var(--ease), background 0.2s;
}
.nav-cta:hover {
  background: #5eead4;
}

/* ───── 通用 ───── */
.eyebrow {
  margin: 0 0 14px;
  font-size: 19px;
  font-weight: 600;
  color: var(--teal);
  letter-spacing: 0.01em;
}
.eyebrow.dark {
  color: var(--teal-d);
}
/* 中文按短语换行：只在标点和空格处断行，太长的短语才在字间断开 */
.display,
.display-2,
.title,
.lead,
.hero-sub,
.pain-card h3,
.feat h3,
.film-cap b {
  word-break: keep-all;
  overflow-wrap: anywhere;
  text-wrap: balance;
}
.display {
  margin: 0;
  font-size: clamp(52px, 9vw, 112px);
  line-height: 1.02;
  font-weight: 700;
  letter-spacing: -0.02em;
}
.display-2 {
  margin: 0;
  font-size: clamp(44px, 7.4vw, 96px);
  line-height: 1.05;
  font-weight: 700;
  letter-spacing: -0.02em;
}
.title {
  margin: 0 0 22px;
  font-size: clamp(38px, 5.6vw, 72px);
  line-height: 1.08;
  font-weight: 700;
  letter-spacing: -0.02em;
}
.lead {
  max-width: 760px;
  margin: 0 0 40px;
  font-size: clamp(19px, 2vw, 24px);
  line-height: 1.5;
  font-weight: 500;
}
.muted {
  color: var(--muted);
}
.grad {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 46px;
  padding: 0 26px;
  border-radius: 980px;
  font-size: 17px;
  font-weight: 600;
  transition: transform 0.25s var(--ease), background 0.25s, box-shadow 0.25s;
}
.btn-primary {
  background: var(--teal);
  color: #031512;
  box-shadow: 0 10px 40px -10px rgba(45, 212, 191, 0.6);
}
.btn-primary:hover {
  background: #5eead4;
  transform: translateY(-1px);
}
.btn-lg {
  height: 56px;
  padding: 0 34px;
  font-size: 19px;
}
.btn-ghost {
  color: var(--fg);
  border: 1px solid rgba(255, 255, 255, 0.22);
  background: rgba(255, 255, 255, 0.02);
}
.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.08);
  transform: translateY(-1px);
}
.btn-link {
  font-size: 19px;
  color: var(--teal);
  font-weight: 500;
}
.btn-link:hover {
  text-decoration: underline;
}
.show-sm {
  display: none;
}

/* 进入视口时淡入上移 */
/* 只有脚本正常运行（html.js）时才先隐藏再淡入；脚本跑不起来的旧浏览器直接显示内容 */
.js .reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 1s var(--ease) var(--d, 0ms), transform 1s var(--ease) var(--d, 0ms);
}
.reveal.in {
  opacity: 1;
  transform: none;
}
/* 首屏不等脚本判断可见：页面一出来就开始淡入 */
@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(28px);
  }
}
.js .hero .reveal {
  opacity: 1;
  transform: none;
  animation: rise 1s var(--ease) var(--d, 0ms) both;
}

/* ───── 首屏 ───── */
.hero {
  position: relative;
  padding: calc(var(--nav-h) + 64px) 0 var(--sec);
  text-align: center;
  overflow: hidden;
}
.hero-copy {
  padding: 0 22px;
}
.hero-sub {
  max-width: 760px;
  margin: 26px auto 34px;
  font-size: clamp(19px, 2.2vw, 26px);
  line-height: 1.45;
  font-weight: 500;
  color: var(--muted);
}
.hero-cta {
  display: flex;
  gap: 30px;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
}
/* 首屏视频：海报 + 播放按钮，点了才加载；外圈光晕跟着画面呼吸 */
.film-stage {
  position: relative;
  max-width: 1180px;
  margin: 52px auto 0;
  padding: 0 22px;
}
.film-glow {
  position: absolute;
  inset: 4% 4% auto;
  height: 82%;
  background: radial-gradient(ellipse at center, rgba(45, 212, 191, 0.3), rgba(34, 211, 238, 0.08) 45%, transparent 70%);
  filter: blur(50px);
  pointer-events: none;
}
.js .film-glow {
  animation: breathe 6s ease-in-out infinite;
}
@keyframes breathe {
  50% {
    opacity: 0.6;
  }
}
.film {
  position: relative;
  aspect-ratio: 16 / 9;
  border-radius: 18px;
  overflow: hidden;
  background: #050607;
  border: 1px solid rgba(255, 255, 255, 0.12);
  box-shadow: 0 60px 120px -30px rgba(0, 0, 0, 0.9), 0 0 0 1px rgba(255, 255, 255, 0.03) inset;
  text-align: left;
}
/* 不支持 aspect-ratio 的旧浏览器：按 16:9 撑开高度 */
@supports not (aspect-ratio: 16 / 9) {
  .film {
    height: 0;
    padding-top: 56.25%;
  }
}
.js .film {
  animation: lay-flat 1.4s cubic-bezier(0.3, 0.1, 0.2, 1) 0.5s backwards;
}
@keyframes lay-flat {
  from {
    opacity: 0;
    transform: perspective(1600px) rotateX(18deg) scale(0.92) translateY(30px);
  }
}
.film video {
  position: absolute;
  inset: 0;
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  background: #000;
}
.film-cover {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 100%;
  margin: 0;
  padding: 0;
  border: 0;
  color: #fff;
  font: inherit;
  text-align: center;
  cursor: pointer;
  background: radial-gradient(ellipse 60% 55% at 50% 50%, rgba(0, 0, 0, 0.05), rgba(0, 0, 0, 0.5)), linear-gradient(180deg, transparent 55%, rgba(0, 0, 0, 0.78));
  transition: opacity 0.4s var(--ease), visibility 0.4s;
}
.film.started .film-cover,
.film.failed .film-cover {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}
.film-btn {
  position: relative;
  display: grid;
  place-items: center;
  width: 96px;
  height: 96px;
  border-radius: 50%;
  background: var(--teal);
  color: #031512;
  box-shadow: 0 0 0 10px rgba(45, 212, 191, 0.18), 0 0 70px rgba(45, 212, 191, 0.65);
  transition: transform 0.3s var(--ease), background 0.3s;
}
.film-btn svg {
  width: 38px;
  height: 38px;
  margin-left: 5px;
}
/* 按钮外一圈慢慢扩散的光环，提示"点这里" */
.film-btn::after {
  content: '';
  position: absolute;
  inset: -10px;
  border-radius: 50%;
  border: 2px solid rgba(45, 212, 191, 0.6);
  animation: ripple 2.4s var(--ease) infinite;
}
@keyframes ripple {
  from {
    transform: scale(0.9);
    opacity: 1;
  }
  to {
    transform: scale(1.5);
    opacity: 0;
  }
}
.film-cover:hover .film-btn,
.film-cover:focus-visible .film-btn {
  transform: scale(1.07);
  background: #5eead4;
}
.film-cap {
  position: absolute;
  left: 28px;
  right: 28px;
  bottom: 24px;
  text-align: left;
}
.film-cap b {
  display: block;
  font-size: clamp(20px, 2.6vw, 30px);
  font-weight: 700;
  letter-spacing: -0.01em;
  text-shadow: 0 2px 24px rgba(0, 0, 0, 0.7);
}
.film-cap small {
  display: block;
  margin-top: 4px;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.78);
}
/* 手机上：横屏全屏按钮 */
.film-full {
  position: absolute;
  right: 12px;
  top: 12px;
  z-index: 2;
  display: none;
  align-items: center;
  gap: 6px;
  height: 32px;
  padding: 0 12px;
  border-radius: 980px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  background: rgba(0, 0, 0, 0.6);
  color: #fff;
  font: inherit;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
}
.film-full svg {
  width: 15px;
  height: 15px;
}
@media (hover: none) and (pointer: coarse) {
  .film-full {
    display: inline-flex;
  }
  /* 开始播放后用播放器自己的全屏按钮（安卓 Chrome 全屏时会自动转横屏） */
  .film.started .film-full {
    display: none;
  }
}
.film-end {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 22px;
  background: rgba(0, 0, 0, 0.78);
  text-align: center;
  animation: fade-in 0.6s var(--ease);
}
.film-end p {
  margin: 0;
  font-size: clamp(26px, 4vw, 48px);
  font-weight: 700;
  letter-spacing: -0.01em;
}
.film-end-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}
.film-end .btn-ghost {
  font: inherit;
  font-size: 17px;
  font-weight: 600;
  cursor: pointer;
}
@keyframes fade-in {
  from {
    opacity: 0;
  }
}
.film-fail {
  position: absolute;
  left: 50%;
  bottom: 22px;
  margin: 0;
  padding: 8px 16px;
  border-radius: 12px;
  transform: translateX(-50%);
  background: rgba(0, 0, 0, 0.75);
  color: var(--muted);
  font-size: 14px;
  white-space: nowrap;
}
.film-chapters {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  margin: 20px 0 0;
  padding: 0;
  list-style: none;
}
.film-chapters button {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 8px 15px;
  border-radius: 980px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.03);
  color: var(--muted);
  font: inherit;
  font-size: 14px;
  white-space: nowrap;
  cursor: pointer;
  transition: color 0.2s, border-color 0.2s, background 0.2s;
}
.film-chapters button:hover {
  color: var(--fg);
  border-color: rgba(255, 255, 255, 0.22);
}
.film-chapters b {
  font-family: var(--mono);
  font-size: 12.5px;
  font-weight: 600;
  color: var(--teal);
}
.film-chapters button.on {
  color: var(--fg);
  border-color: rgba(45, 212, 191, 0.5);
  background: rgba(45, 212, 191, 0.09);
}
.film-note {
  max-width: 820px;
  margin: 16px auto 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--dim);
}

/* 实录里的数字 */
.num {
  font-variant-numeric: tabular-nums;
}
.proof {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  max-width: 1080px;
  margin: 60px auto 0;
  padding: 0 22px;
  list-style: none;
}
.proof li {
  padding: 4px 16px;
  border-left: 1px solid var(--line);
}
.proof li:first-child {
  border-left: 0;
}
.proof b {
  display: block;
  font-size: clamp(44px, 5.4vw, 68px);
  line-height: 1;
  font-weight: 700;
  letter-spacing: -0.02em;
}
.proof b small {
  margin-left: 4px;
  font-size: 0.36em;
  font-weight: 600;
  letter-spacing: 0;
  color: var(--muted);
  -webkit-text-fill-color: var(--muted);
}
.proof li > span {
  display: block;
  text-wrap: balance;
  margin-top: 10px;
  font-size: 14px;
  line-height: 1.5;
  color: var(--muted);
}

/* ───── 宣言：进入视口后逐字点亮 ───── */
.statement {
  padding: var(--sec) 0;
}
.scrub {
  max-width: 980px;
  margin: 0 auto;
  padding: 0 22px;
  font-size: clamp(34px, 5.2vw, 68px);
  line-height: 1.22;
  font-weight: 700;
  letter-spacing: -0.015em;
  text-align: center;
}
.js .scrub span {
  color: rgba(245, 245, 247, 0.16);
  transition: color 0.25s linear;
}
.scrub span.lit {
  color: var(--fg);
}
.scrub span.lit.hl {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

/* ───── 浅色区块 ───── */
.light {
  background: var(--light);
  color: var(--light-fg);
}
.light .lead {
  color: var(--light-muted);
}

/* ───── 痛点 ───── */
.pain {
  padding: var(--sec) 0;
}
.pain-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}
.pain-card {
  display: flex;
  flex-direction: column;
  padding: 28px 26px 24px;
  border-radius: 24px;
  background: #fff;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 24px 48px -34px rgba(0, 0, 0, 0.3);
}
.pain-card h3 {
  margin: 0 0 14px;
  font-size: 22px;
  line-height: 1.3;
  letter-spacing: -0.01em;
}
.pain-card p {
  margin: 0;
  font-size: 15px;
  line-height: 1.65;
}
.pain-card .was {
  margin-bottom: 18px;
  color: var(--light-muted);
}
.pain-card .now {
  margin-top: auto;
  padding-top: 16px;
  border-top: 1px solid #e8e8ed;
  font-weight: 600;
}
.pain-card .tag {
  display: inline-block;
  margin-right: 8px;
  padding: 0 8px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 600;
  line-height: 20px;
  vertical-align: 1px;
  background: #ececf0;
  color: #86868b;
}
.pain-card .now .tag {
  background: rgba(13, 148, 136, 0.12);
  color: var(--teal-d);
}

/* ───── 和通用 AI 的对比 ───── */
.versus {
  padding: var(--sec) 0;
  background: radial-gradient(1000px 520px at 85% 0%, rgba(45, 212, 191, 0.09), transparent 60%), #000;
}
.vs {
  border: 1px solid var(--line);
  border-radius: 24px;
  overflow: hidden;
  background: #0b0c0e;
}
.vs-head,
.vs-row {
  display: grid;
  grid-template-columns: 1fr 1.2fr 1.5fr;
}
.vs-head span {
  padding: 16px 24px;
  font-size: 14px;
  font-weight: 600;
  color: var(--dim);
}
.vs-head span:last-child,
.vs-row .yes {
  background: rgba(45, 212, 191, 0.06);
}
.vs-head span:last-child {
  color: var(--teal);
  font-size: 15px;
}
.vs-row > * {
  padding: 17px 24px;
  border-top: 1px solid var(--line);
  font-size: 15px;
  line-height: 1.55;
}
.vs-row b {
  font-weight: 600;
}
.vs-row .no {
  color: var(--dim);
}
.vs-row .yes {
  color: #e6fffb;
  font-weight: 500;
}
.vs-row .no::before,
.vs-row .yes::before {
  display: inline-block;
  width: 22px;
  font-weight: 700;
}
.vs-row .no::before {
  content: '✕';
  color: #55555a;
}
.vs-row .yes::before {
  content: '✓';
  color: var(--teal);
}

/* ───── 开发闭环 ───── */
.loop {
  padding: var(--sec) 0;
  text-align: center;
}
.loop .lead {
  margin-left: auto;
  margin-right: auto;
}
.ring-wrap {
  position: relative;
  max-width: 640px;
  margin: 30px auto 0;
  aspect-ratio: 1;
}
.ring {
  position: absolute;
  inset: 0;
}
.ring-svg {
  width: 100%;
  height: 100%;
  transform: rotate(-90deg);
}
.ring-track {
  fill: none;
  stroke: rgba(255, 255, 255, 0.08);
  stroke-width: 2;
}
.ring-run {
  fill: none;
  stroke: url(#lg-ring);
  stroke-width: 3;
  stroke-linecap: round;
  stroke-dasharray: 0 600;
  transition: stroke-dasharray 1.1s var(--ease);
  filter: drop-shadow(0 0 8px rgba(45, 212, 191, 0.7));
}
.ring-center {
  position: absolute;
  inset: 28%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
}
.ring-center b {
  font-size: clamp(26px, 3.6vw, 40px);
  letter-spacing: -0.01em;
}
.ring-center span {
  font-size: 15px;
  line-height: 1.55;
  color: var(--muted);
}
.ring-center.swap b,
.ring-center.swap span {
  animation: swap 0.6s var(--ease);
}
@keyframes swap {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
}
.ring-nodes {
  position: absolute;
  inset: 0;
  margin: 0;
  padding: 0;
  list-style: none;
}
.ring-nodes li {
  position: absolute;
  left: 50%;
  top: 50%;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  width: 120px;
  margin: -24px 0 0 -60px;
  transform: translate(var(--x), var(--y));
  cursor: pointer;
}
.ring-nodes i {
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  font-style: normal;
  font-weight: 700;
  background: #0b0d10;
  border: 1px solid rgba(255, 255, 255, 0.16);
  color: var(--muted);
  transition: all 0.5s var(--ease);
}
.ring-nodes span {
  font-size: 14px;
  font-weight: 600;
  color: var(--dim);
  transition: color 0.5s;
  white-space: nowrap;
}
.ring-nodes li.past i {
  border-color: rgba(45, 212, 191, 0.5);
  color: var(--teal);
}
.ring-nodes li.active i {
  background: var(--teal);
  border-color: var(--teal);
  color: #031512;
  box-shadow: 0 0 0 8px rgba(45, 212, 191, 0.15), 0 0 30px rgba(45, 212, 191, 0.7);
  transform: scale(1.12);
}
.ring-nodes li.active span,
.ring-nodes li.past span {
  color: var(--fg);
}

/* ───── 能做什么 ───── */
.features {
  padding: var(--sec) 0;
}
.feat-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}
.feat {
  display: flex;
  flex-direction: column;
  padding: 28px 26px 22px;
  border-radius: 24px;
  background: #fff;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 24px 48px -34px rgba(0, 0, 0, 0.3);
  transition: transform 0.4s var(--ease), box-shadow 0.4s var(--ease);
}
.feat:hover {
  transform: translateY(-3px);
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 30px 60px -34px rgba(0, 0, 0, 0.38);
}
.feat-k {
  margin: 0 0 8px;
  font-size: 14px;
  font-weight: 600;
  color: var(--teal-d);
}
.feat h3 {
  margin: 0 0 12px;
  font-size: 24px;
  line-height: 1.25;
  letter-spacing: -0.01em;
}
.feat > p {
  margin: 0;
  font-size: 15px;
  line-height: 1.65;
  color: var(--light-muted);
}
.feat .code-vis,
.feat .facts-vis {
  margin-top: 18px;
}
.feat > .feat-on {
  margin-top: auto;
  padding-top: 18px;
  font-size: 12.5px;
  font-weight: 600;
  color: #86868b;
}
.code-vis {
  padding: 14px 16px;
  border-radius: 14px;
  background: #0b0d10;
  border: 1px solid rgba(0, 0, 0, 0.06);
  font-family: var(--mono);
  font-size: 12.5px;
  line-height: 1.9;
  color: #d4d4d8;
  white-space: nowrap;
  overflow: hidden;
}
.code-vis span {
  color: var(--teal);
}
.code-vis em {
  font-style: normal;
  color: var(--dim);
}
.code-vis b {
  color: var(--bad);
  font-weight: 600;
}
.facts-vis {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.facts-vis span {
  padding: 9px 14px;
  border-radius: 12px;
  background: rgba(13, 148, 136, 0.07);
  border: 1px solid rgba(13, 148, 136, 0.2);
  font-size: 14px;
  color: #0f5f58;
}

/* ───── 技能 ───── */
.skills {
  padding: var(--sec) 0;
  background: radial-gradient(1200px 600px at 50% 0%, rgba(45, 212, 191, 0.08), transparent 60%), #000;
}
.skill-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}
.skill {
  position: relative;
  padding: 30px 28px 28px;
  border-radius: 26px;
  background: #0f1012;
  border: 1px solid var(--line);
  overflow: hidden;
  transition: transform 0.4s var(--ease), border-color 0.4s;
}
.skill::before {
  content: '';
  position: absolute;
  inset: -1px -1px auto;
  height: 4px;
  background: var(--c, var(--teal));
  opacity: 0.85;
}
.skill:hover {
  transform: translateY(-4px);
  border-color: rgba(255, 255, 255, 0.2);
}
.skill-top {
  display: flex;
  min-height: 26px;
}
.chip {
  padding: 3px 10px;
  border-radius: 980px;
  font-size: 12px;
  color: var(--muted);
  border: 1px solid var(--line);
}
.chip.live {
  color: #031512;
  background: var(--teal);
  border-color: transparent;
  font-weight: 600;
}
.skill h3 {
  margin: 16px 0 2px;
  font-size: 30px;
  letter-spacing: -0.01em;
}
.skill-sub {
  margin: 0 0 18px;
  font-size: 14px;
  color: var(--dim);
}
.skill ul {
  margin: 0;
  padding: 0;
  list-style: none;
  font-size: 15px;
  color: #d4d4d8;
}
.skill li {
  position: relative;
  padding: 6px 0 6px 18px;
  line-height: 1.45;
}
.skill li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 14px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--c, var(--teal));
}
.skill.all {
  background: linear-gradient(160deg, rgba(45, 212, 191, 0.16), rgba(34, 211, 238, 0.04) 60%), #0f1012;
}
.skill.all::before {
  background: var(--grad);
}
.all-list li {
  padding: 8px 0 8px 18px;
}
.all-list b {
  display: block;
  font-size: 16px;
  color: var(--fg);
}
.all-list li::before {
  background: var(--teal);
}

/* ───── 网页 HMI ───── */
.hmi {
  padding: var(--sec) 0;
  background: linear-gradient(180deg, #000, #05080a 40%, #000);
}
/* 示例画面切换：分段控件样式的标签；自动轮换时，当前标签下方的细线显示还有多久换下一个 */
.hmi-demo {
  margin: 10px 0 46px;
}
.hmi-tabs {
  display: flex;
  gap: 2px;
  width: max-content;
  max-width: 100%;
  margin: 0 auto 18px;
  padding: 4px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.05);
}
.hmi-tab {
  position: relative;
  flex: 1 1 auto;
  margin: 0;
  padding: 8px 20px;
  border: 0;
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-size: 14px;
  font-weight: 600;
  white-space: nowrap;
  cursor: pointer;
  overflow: hidden;
  -webkit-appearance: none;
  appearance: none;
  transition: color 0.25s, background 0.25s;
}
.hmi-tab:hover {
  color: var(--fg);
}
.hmi-tab.on {
  background: rgba(255, 255, 255, 0.13);
  color: var(--fg);
}
.hmi-tab:focus-visible {
  outline: 2px solid var(--teal);
  outline-offset: 2px;
}
.hmi-tab::after {
  content: '';
  position: absolute;
  left: 20px;
  right: 20px;
  bottom: 3px;
  height: 2px;
  border-radius: 2px;
  background: var(--teal);
  opacity: 0;
  transform: scaleX(0);
  transform-origin: left center;
}
.rotating .hmi-tab.on::after {
  opacity: 0.9;
  animation: hmi-progress 8s linear forwards;
}
@keyframes hmi-progress {
  to {
    transform: scaleX(1);
  }
}

/* 四个画面叠在同一格里：框的高度取最高的那个，切换时下面的内容不跳动 */
.hmi-frame {
  display: grid;
  border-radius: 22px;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.12);
  background: #15181d;
  box-shadow: 0 50px 100px -40px rgba(34, 211, 238, 0.35);
  font-size: 13px;
}
.hmi-screen {
  position: relative;
  grid-area: 1 / 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
  visibility: hidden;
  opacity: 0;
  transition: opacity 0.45s var(--ease), visibility 0s linear 0.45s;
}
.hmi-screen.on {
  visibility: visible;
  opacity: 1;
  transition: opacity 0.45s var(--ease);
}
.hmi-vis {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
}
/* 只给读屏软件看的说明 */
.vh {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}
.hmi-head {
  display: flex;
  align-items: center;
  gap: 18px;
  height: 46px;
  padding: 0 18px;
  background: #1d2128;
  border-bottom: 1px solid #333a45;
  white-space: nowrap;
}
.hmi-head b {
  font-size: 15px;
}
.hmi-nav {
  display: flex;
  gap: 4px;
}
.hmi-nav em {
  padding: 6px 12px;
  border-radius: 6px;
  font-style: normal;
  color: #9aa3b2;
}
.hmi-nav em.on {
  background: #252a33;
  color: #e5e7eb;
  box-shadow: inset 0 -2px 0 var(--cyan);
}
.hmi-status {
  margin-left: auto;
  color: #9aa3b2;
}
.hmi-status i {
  display: inline-block;
  width: 8px;
  height: 8px;
  margin-right: 6px;
  border-radius: 50%;
  background: #22c55e;
}
.hmi-clock {
  color: #9aa3b2;
  font-variant-numeric: tabular-nums;
}
/* 报警栏一直占位：平时显示"无活动报警"，报警时变红，画面高度不变 */
.hmi-alarm {
  display: flex;
  align-items: center;
  gap: 10px;
  min-height: 34px;
  padding: 6px 18px;
  background: #171a20;
  border-bottom: 1px solid #2a303a;
  color: #7c8594;
  font-size: 12.5px;
  white-space: nowrap;
  transition: background 0.3s, color 0.3s;
}
.hmi-alarm::before {
  content: '';
  flex-shrink: 0;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #22c55e;
}
.hmi-alarm .a-msg,
.hmi-alarm .a-ack {
  display: none;
}
.hmi-alarm.on {
  background: #ef4444;
  border-bottom-color: #ef4444;
  color: #fff;
  font-weight: 600;
}
.hmi-alarm.on::before {
  background: #fff;
  animation: blink 1s steps(2) infinite;
}
.hmi-alarm.on .a-ok {
  display: none;
}
.hmi-alarm.on .a-msg {
  display: block;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
}
.hmi-alarm.on .a-ack {
  display: block;
  flex-shrink: 0;
  margin-left: auto;
  padding: 2px 10px;
  border-radius: 6px;
  background: rgba(0, 0, 0, 0.25);
  font-size: 12px;
}
/* 画面比最高的那个矮时，多出的高度给最下面一行（趋势图、柱状图跟着变高） */
.hmi-body {
  flex: 1;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  grid-template-rows: auto 1fr;
  gap: 14px;
  padding: 18px;
}
.hmi-panel {
  min-width: 0;
  padding: 14px 16px;
  border-radius: 10px;
  background: #1d2128;
  border: 1px solid #333a45;
}
.hmi-panel.wide {
  grid-column: 1 / -1;
  display: flex;
  flex-direction: column;
}
.hmi-panel.wide .hmi-trend,
.hmi-panel.wide .hmi-hours {
  flex: 1 0 110px;
  height: auto;
}
.hmi-panel h4 {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 12px;
  font-size: 13px;
  color: #9aa3b2;
  font-weight: 600;
  white-space: nowrap;
}
.hmi-legend {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  margin-left: auto;
  font-size: 12px;
  font-weight: 400;
}
.hmi-legend i {
  display: inline-block;
  width: 10px;
  height: 10px;
  margin-left: 6px;
  border-radius: 2px;
}
.hmi-tank {
  position: relative;
  height: 150px;
  width: 72px;
  border-radius: 8px;
  background: #11141a;
  border: 1px solid #333a45;
  overflow: hidden;
}
.hmi-fill {
  position: absolute;
  inset: auto 0 0;
  height: 50%;
  background: linear-gradient(180deg, #38bdf8, #0369a1);
  transition: height 0.4s linear, background 0.4s;
}
.hmi-fill.alarm {
  background: linear-gradient(180deg, #f87171, #b91c1c);
}
.hmi-tank span {
  position: absolute;
  inset: auto 0 6px;
  text-align: center;
  font-weight: 700;
  font-size: 12px;
  font-variant-numeric: tabular-nums;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.6);
}
.hmi-gauge {
  display: block;
  width: 100%;
  max-width: 150px;
}
.g-track,
.g-val {
  fill: none;
  stroke-width: 10;
  stroke-linecap: round;
}
.g-track {
  stroke: #252a33;
}
.g-val {
  stroke: #38bdf8;
  stroke-dasharray: 50 100;
  transition: stroke-dasharray 0.4s linear, stroke 0.4s;
}
.g-val.warn {
  stroke: #f59e0b;
}
.hmi-gauge text {
  fill: #e5e7eb;
  font-size: 18px;
  font-weight: 700;
  text-anchor: middle;
  font-family: var(--font);
}
.hmi-gauge .g-unit {
  fill: #9aa3b2;
  font-size: 10px;
  font-weight: 400;
}
.hmi-kv {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 8px 14px;
  align-items: center;
  color: #9aa3b2;
}
.hmi-kv b {
  color: #e5e7eb;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}
.lamp {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: #e5e7eb;
}
.lamp::before {
  content: '';
  flex-shrink: 0;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: #22c55e;
  box-shadow: 0 0 10px #22c55e;
  transition: background 0.3s, box-shadow 0.3s;
}
.lamp.warn::before {
  background: #f59e0b;
  box-shadow: 0 0 10px #f59e0b;
}
.lamp.bad::before {
  background: #ef4444;
  box-shadow: 0 0 12px #ef4444;
}
.lamp.off::before {
  background: #4b5563;
  box-shadow: none;
}
.hmi-btns {
  display: flex;
  gap: 8px;
  margin-top: 14px;
}
.hb {
  flex: 1;
  padding: 9px 0;
  text-align: center;
  border-radius: 6px;
  background: #2b313b;
  border: 1px solid #333a45;
  font-weight: 600;
}
.hb.start {
  border-color: #22c55e;
}
.hb.stop {
  border-color: #ef4444;
}
.hmi-trend {
  width: 100%;
  height: 110px;
  display: block;
}
.hmi-trend polyline {
  fill: none;
  stroke: #38bdf8;
  stroke-width: 2;
  vector-effect: non-scaling-stroke;
}
.hmi-trend polyline.sv {
  stroke: #9aa3b2;
  stroke-width: 1.5;
  stroke-dasharray: 6 5;
}
.hmi-trend polyline.hot {
  stroke: #fb923c;
}
.l-sv {
  background: repeating-linear-gradient(90deg, #9aa3b2 0 4px, transparent 4px 6px);
  height: 2px !important;
}
.l-pv {
  background: #fb923c;
  height: 2px !important;
}

/* 大号读数、分拣去向、机组 / 电机列表 */
.hmi-big {
  display: flex;
  align-items: baseline;
  gap: 6px;
  margin: 0 0 12px;
  white-space: nowrap;
}
.hmi-big b {
  font-size: 34px;
  line-height: 1.1;
  font-weight: 700;
  color: #f3f4f6;
  letter-spacing: -0.01em;
  font-variant-numeric: tabular-nums;
}
.hmi-big small {
  color: #9aa3b2;
  font-size: 13px;
}
.hmi-lanes {
  display: grid;
  gap: 14px;
  padding-top: 4px;
}
.hmi-lanes div {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  align-items: center;
  gap: 10px;
  color: #9aa3b2;
  white-space: nowrap;
}
.hmi-lanes i {
  height: 10px;
  border-radius: 5px;
  background: #11141a;
  border: 1px solid #2a303a;
  overflow: hidden;
}
.hmi-lanes em {
  display: block;
  width: 0;
  height: 100%;
  border-radius: 5px;
  background: var(--lane);
  transition: width 0.4s linear;
}
.hmi-lanes b {
  min-width: 3.4em;
  text-align: right;
  color: #e5e7eb;
  font-variant-numeric: tabular-nums;
}
.lane-a {
  --lane: #38bdf8;
}
.lane-b {
  --lane: #f59e0b;
}
.lane-c {
  --lane: #a78bfa;
}
.hmi-units {
  display: grid;
  gap: 11px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.hmi-units li {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #cbd2dc;
  white-space: nowrap;
}
.hmi-units b {
  margin-left: auto;
  color: #e5e7eb;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
}

/* 输送线：皮带滚动、包裹按去向分到三个分拣口，堵料时皮带停住 */
.hmi-line {
  display: block;
  width: 100%;
  height: auto;
  margin: auto 0; /* 这一行被拉高时，线体在面板里上下居中 */
}
.hmi-line .belt {
  fill: #11141a;
  stroke: #333a45;
}
.hmi-line .belt-run {
  stroke: #262c36;
  stroke-width: 22;
  stroke-dasharray: 2 14;
}
.hmi-screen.on .belt-run {
  animation: belt 0.55s linear infinite;
}
.hmi-line.stopped .belt-run {
  animation-play-state: paused;
}
@keyframes belt {
  to {
    stroke-dashoffset: -16;
  }
}
.chute rect {
  fill: #11141a;
  stroke: #333a45;
}
.chute text,
.line-k {
  fill: #7c8594;
  font-size: 11px;
  text-anchor: middle;
  font-family: var(--font);
}
.line-k {
  font-size: 11px;
  text-anchor: start;
}
.line-k.end {
  text-anchor: end;
}
.eye {
  fill: #1f2937;
  stroke: #4b5563;
  stroke-width: 1.5;
  transition: fill 0.2s, stroke 0.2s;
}
.eye.on {
  fill: #22c55e;
  stroke: #22c55e;
}
.eye.bad {
  fill: #ef4444;
  stroke: #ef4444;
}
.parcel {
  transition: transform 0.5s linear, opacity 0.35s;
}
.parcel.jump {
  transition: none;
}
.parcel.lane-a {
  fill: #38bdf8;
}
.parcel.lane-b {
  fill: #f59e0b;
}
.parcel.lane-c {
  fill: #a78bfa;
}
.parcel.jam {
  fill: #ef4444;
}

/* 逐时用电柱状图：按峰 / 平 / 谷电价时段着色，最右边是当前小时（实时增长） */
.hmi-hours {
  display: flex;
  align-items: flex-end;
  gap: 3px;
  height: 110px;
}
.hmi-hours i {
  flex: 1;
  min-width: 0;
  border-radius: 3px 3px 0 0;
  opacity: 0.82;
  transition: height 0.4s linear;
}
.hmi-hours i.now {
  opacity: 1;
}
.t-peak {
  background: #f59e0b;
}
.t-flat {
  background: #38bdf8;
}
.t-valley {
  background: #14b8a6;
}

/* 烘箱：工艺段、加热输出 */
.hmi-steps {
  display: flex;
  gap: 6px;
  margin: 0 0 14px;
  padding: 0;
  list-style: none;
}
.hmi-steps li {
  flex: 1;
  padding: 6px 0;
  text-align: center;
  border-radius: 6px;
  background: #11141a;
  border: 1px solid #2a303a;
  color: #6b7280;
  font-weight: 600;
  font-size: 12.5px;
  white-space: nowrap;
  transition: background 0.3s, border-color 0.3s, color 0.3s;
}
.hmi-steps li.done {
  color: #9aa3b2;
}
.hmi-steps li.on {
  background: rgba(34, 211, 238, 0.12);
  border-color: var(--cyan);
  color: #e5e7eb;
}
.hmi-meter {
  height: 10px;
  margin-top: 14px;
  border-radius: 5px;
  background: #11141a;
  border: 1px solid #2a303a;
  overflow: hidden;
}
.hmi-meter i {
  display: block;
  width: 0;
  height: 100%;
  background: linear-gradient(90deg, #f59e0b, #ef4444);
  transition: width 0.4s linear;
}
.hmi-points {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 26px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.hmi-points b {
  display: block;
  margin-bottom: 6px;
  font-size: 19px;
}
.hmi-points span {
  color: var(--muted);
  font-size: 15px;
}

/* ───── 安全 ───── */
.safety {
  padding: var(--sec) 0;
  background: #000;
}
.safety-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.safety-copy .lead {
  font-size: clamp(17px, 1.7vw, 21px);
}
.gates {
  margin: 0;
  padding: 0;
  list-style: none;
  position: relative;
}
.gates::before {
  content: '';
  position: absolute;
  left: 21px;
  top: 22px;
  bottom: 22px;
  width: 2px;
  background: rgba(255, 255, 255, 0.08);
}
.gates li {
  position: relative;
  display: grid;
  grid-template-columns: 44px 1fr;
  column-gap: 18px;
  padding: 10px 0;
}
/* 有脚本时先变暗，进入视口后一道道点亮 */
.js .gates li {
  opacity: 0.25;
  transition: opacity 0.5s var(--ease);
}
.js .gates li.on {
  opacity: 1;
}
.gates i {
  grid-row: span 2;
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  font-style: normal;
  font-weight: 700;
  background: #0b0d10;
  border: 1px solid rgba(255, 255, 255, 0.16);
  color: var(--muted);
  transition: all 0.5s var(--ease);
  z-index: 1;
}
.gates li.on i,
html:not(.js) .gates i {
  background: var(--teal);
  color: #031512;
  border-color: var(--teal);
  box-shadow: 0 0 24px rgba(45, 212, 191, 0.55);
}
.gates b {
  font-size: 20px;
  align-self: end;
}
.gates span {
  font-size: 15px;
  color: var(--muted);
}

/* ───── 版本 ───── */
.history {
  padding: var(--sec) 0;
}
.history-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}
.versions {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.ver {
  position: relative;
  display: grid;
  grid-template-columns: 52px 1fr auto;
  align-items: center;
  gap: 4px 14px;
  padding: 18px 20px;
  border-radius: 18px;
  background: #fff;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 20px 40px -30px rgba(0, 0, 0, 0.25);
}
.ver b {
  grid-row: span 2;
  font-family: var(--mono);
  font-size: 20px;
  color: var(--teal-d);
}
.ver p {
  grid-column: 2;
  margin: 0;
  font-size: 15px;
  font-weight: 600;
}
.ver em {
  grid-column: 3;
  grid-row: 1 / span 2;
  font-style: normal;
  font-family: var(--mono);
  font-size: 13px;
  color: var(--light-muted);
}
.who {
  grid-column: 2;
  grid-row: 2;
  justify-self: start;
  order: 3;
  font-size: 12px;
  padding: 1px 8px;
  border-radius: 6px;
  background: #e8e8ed;
  color: #6e6e73;
}
.who.ai {
  background: rgba(13, 148, 136, 0.1);
  color: var(--teal-d);
}
.rollback {
  position: absolute;
  right: 20px;
  bottom: -11px;
  padding: 3px 12px;
  border-radius: 980px;
  background: var(--light-fg);
  color: #fff;
  font-size: 12px;
}

/* ───── 免安装 ───── */
.install {
  padding: var(--sec) 0;
  text-align: center;
}
.install .lead {
  margin-left: auto;
  margin-right: auto;
}
.install-row {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
  max-width: 900px;
  margin: 0 auto;
}
.install-row div {
  padding: 26px 16px;
  border-radius: 22px;
  background: #0f1012;
  border: 1px solid var(--line);
}
.install-row b {
  display: block;
  font-size: 40px;
  line-height: 1;
  margin-bottom: 12px;
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.install-row span {
  font-size: 16px;
  color: #d4d4d8;
}

/* ───── 开始 ───── */
.cta {
  padding: var(--sec) 0 calc(var(--sec) + 16px);
  text-align: center;
  background: radial-gradient(900px 500px at 50% 100%, rgba(45, 212, 191, 0.16), transparent 70%), #000;
}
.cta-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 14px;
  margin: 46px 0 16px;
}
.cta-meta {
  margin: 0;
  color: var(--dim);
  font-size: 14px;
}
.cta-note {
  margin: 26px 0 0;
  color: var(--muted);
  font-size: 15px;
}
.cta-note a {
  color: var(--teal);
}
.cta-note a:hover {
  text-decoration: underline;
}

/* ───── 页脚 ───── */
.footer {
  padding: 30px 0 40px;
  border-top: 1px solid var(--line);
  font-size: 12px;
  color: var(--dim);
}
.footer-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 30px;
  align-items: center;
  justify-content: space-between;
}
.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--muted);
}
.footer-legal {
  margin: 0;
}
.footer-legal a {
  color: var(--muted);
}
.footer-legal a:hover {
  color: var(--fg);
}
.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
  width: 100%;
  margin: 0;
}
.footer-links a {
  color: var(--muted);
}
.footer-links a:hover {
  color: var(--fg);
}
.footer-links span:empty {
  display: none;
}

/* ───── 联系我们 ───── */
.modal-open,
.modal-open body {
  overflow: hidden;
}
.modal {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: grid;
  place-items: center;
  padding: 20px;
}
.modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.62);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  opacity: 0;
  transition: opacity 0.26s var(--ease);
}
.modal-sheet {
  position: relative;
  width: min(880px, 100%);
  max-height: calc(100vh - 40px);
  overflow: auto;
  padding: 44px 36px 34px;
  border-radius: 28px;
  border: 1px solid rgba(255, 255, 255, 0.09);
  background: radial-gradient(600px 300px at 50% 0%, rgba(45, 212, 191, 0.1), transparent 70%), #111316;
  box-shadow: 0 40px 120px rgba(0, 0, 0, 0.6);
  opacity: 0;
  transform: translateY(18px) scale(0.98);
  transition: opacity 0.26s var(--ease), transform 0.26s var(--ease);
}
.modal.open .modal-backdrop {
  opacity: 1;
}
.modal.open .modal-sheet {
  opacity: 1;
  transform: none;
}
.modal-close {
  position: absolute;
  top: 16px;
  right: 16px;
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  color: var(--muted);
  background: rgba(255, 255, 255, 0.06);
  transition: background 0.2s, color 0.2s;
}
.modal-close:hover {
  color: var(--fg);
  background: rgba(255, 255, 255, 0.12);
}
.modal-close svg {
  width: 18px;
  height: 18px;
}
.modal-title {
  margin: 0;
  text-align: center;
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 700;
  letter-spacing: -0.01em;
}
.modal-sub {
  margin: 10px auto 0;
  max-width: 520px;
  text-align: center;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.6;
}
.contact-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 30px;
}
.contact-grid[data-count='1'] {
  grid-template-columns: minmax(0, 300px);
  justify-content: center;
}
.contact-grid[data-count='2'] {
  grid-template-columns: repeat(2, minmax(0, 300px));
  justify-content: center;
}
.contact-card {
  margin: 0;
  padding: 22px 18px 20px;
  border-radius: 20px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.035);
  text-align: center;
}
.contact-card .qr {
  width: min(180px, 100%);
  aspect-ratio: 1;
  margin: 0 auto 16px;
  padding: 10px;
  border-radius: 14px;
  background: #fff;
}
.contact-card .qr img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
}
.contact-card figcaption b {
  display: block;
  font-size: 17px;
  font-weight: 600;
  word-break: break-all;
}
.contact-card figcaption span {
  display: block;
  margin-top: 6px;
  color: var(--muted);
  font-size: 14px;
}
.contact-card figcaption small {
  display: block;
  margin-top: 6px;
  color: var(--dim);
  font-size: 12.5px;
  line-height: 1.5;
}
.copy-btn {
  margin-left: 8px;
  padding: 2px 10px;
  border-radius: 980px;
  border: 1px solid rgba(45, 212, 191, 0.45);
  background: transparent;
  color: var(--teal);
  font: inherit;
  font-size: 12px;
  cursor: pointer;
  transition: background 0.2s;
}
.copy-btn:hover {
  background: rgba(45, 212, 191, 0.12);
}
/* 手机上二维码就在访客自己的屏幕上，扫不了：QQ 给出"打开 QQ 加群"按钮，微信提示长按识别 */
.contact-open {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 36px;
  margin-top: 12px;
  padding: 0 18px;
  border-radius: 980px;
  background: var(--teal);
  color: #031512;
  font-size: 14px;
  font-weight: 600;
}
.contact-open:hover {
  background: #5eead4;
}
.contact-card figcaption .contact-hint {
  margin-top: 10px;
  padding: 8px 12px;
  border-radius: 12px;
  border: 1px solid rgba(45, 212, 191, 0.22);
  background: rgba(45, 212, 191, 0.07);
  color: #99f6e4;
  font-size: 13px;
  line-height: 1.5;
}
.contact-hint .copy-btn {
  margin-top: 6px;
}
/* 商务合作：单独一行 */
.contact-mail {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 8px 14px;
  max-width: 560px;
  margin: 16px auto 0;
  padding: 14px 20px;
  border-radius: 18px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.035);
}
.contact-grid[hidden] + .contact-mail {
  margin-top: 30px;
}
.mail-k {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--muted);
  font-size: 14px;
}
.mail-k svg {
  width: 18px;
  height: 18px;
  color: var(--teal);
}
.contact-mail a {
  color: var(--fg);
  font-size: 17px;
  font-weight: 600;
  word-break: break-all;
}
.contact-mail a:hover {
  color: var(--teal);
  text-decoration: underline;
}
.contact-mail .copy-btn {
  margin-left: 0;
}
.contact-empty {
  margin: 30px 0 6px;
  text-align: center;
  color: var(--muted);
}

/* ───── 窄屏 ───── */
@media (max-width: 1060px) {
  :root {
    --sec: 88px;
  }
  .skill-grid,
  .pain-grid,
  .feat-grid,
  .hmi-points {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .vs-head,
  .vs-row {
    grid-template-columns: 0.9fr 1.1fr 1.4fr;
  }
  .vs-head span,
  .vs-row > * {
    padding-left: 18px;
    padding-right: 18px;
  }
}
@media (max-width: 760px) {
  :root {
    --sec: 64px;
  }
  body {
    font-size: 16px;
  }
  .nav-links {
    display: none;
  }
  .nav-contact {
    margin-left: auto;
  }
  .contact-grid,
  .contact-grid[data-count='2'] {
    grid-template-columns: minmax(0, 300px);
    justify-content: center;
  }
  .modal-sheet {
    padding: 40px 18px 24px;
    border-radius: 22px;
  }
  .contact-mail {
    max-width: 300px;
    padding: 14px 16px;
  }
  .hide-sm {
    display: none;
  }
  .show-sm {
    display: inline;
  }
  .hero {
    padding-top: calc(var(--nav-h) + 56px);
  }
  .film-stage {
    margin-top: 40px;
    padding: 0 12px;
  }
  .film {
    border-radius: 12px;
  }
  .film-btn {
    width: 66px;
    height: 66px;
  }
  .film-btn svg {
    width: 28px;
    height: 28px;
    margin-left: 4px;
  }
  .film-cap {
    left: 14px;
    right: 14px;
    bottom: 10px;
  }
  .film-cap b {
    font-size: 16px;
  }
  .film-cap small {
    font-size: 11.5px;
  }
  .film-full {
    right: 10px;
    top: 9px;
    height: 28px;
    padding: 0 10px;
    font-size: 12px;
  }
  /* 章节：一行横着滑 */
  .film-chapters {
    flex-wrap: nowrap;
    justify-content: flex-start;
    gap: 8px;
    margin: 14px -12px 0;
    padding: 0 12px 4px;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
  }
  .film-chapters::-webkit-scrollbar {
    display: none;
  }
  .film-chapters li {
    flex: none;
  }
  .film-chapters button {
    padding: 7px 12px;
    font-size: 13px;
  }
  .film-note {
    margin-top: 12px;
    font-size: 13px;
    text-align: left;
  }
  .film-end {
    gap: 14px;
  }
  .film-end .btn {
    height: 40px;
    padding: 0 18px;
    font-size: 15px;
  }
  .proof {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    row-gap: 28px;
    margin-top: 44px;
    padding: 0 12px;
  }
  .proof li:nth-child(3) {
    border-left: 0;
  }
  .proof b {
    font-size: 44px;
  }
  .proof li > span {
    font-size: 13px;
  }
  .pain-card,
  .feat {
    padding: 24px 22px 20px;
    border-radius: 20px;
  }
  /* 对比表：每一行变成一张卡片，两种做法上下排 */
  .vs {
    display: grid;
    gap: 12px;
    border: 0;
    border-radius: 0;
    background: none;
    overflow: visible;
  }
  .vs-head {
    display: none;
  }
  .vs-row {
    display: block;
    padding: 18px 16px 16px;
    border-radius: 18px;
    border: 1px solid var(--line);
    background: #0b0c0e;
  }
  .vs-row > * {
    display: block;
    padding: 0 12px;
    border: 0;
  }
  .vs-row b {
    margin-bottom: 10px;
    font-size: 16px;
  }
  .vs-row .yes {
    margin-top: 10px;
    padding: 10px 12px;
    border-radius: 12px;
  }
  .vs-row .no::before {
    content: '✕ 通用 AI：';
    width: auto;
    font-weight: 600;
  }
  .vs-row .yes::before {
    content: '✓ OT Code：';
    width: auto;
  }
  .ring-wrap {
    aspect-ratio: auto;
  }
  .ring {
    display: none;
  }
  .ring-nodes {
    position: static;
    display: grid;
    gap: 12px;
    text-align: left;
  }
  .ring-nodes li {
    position: static;
    transform: none;
    margin: 0;
    width: auto;
    flex-direction: row;
    align-items: flex-start;
    gap: 14px;
  }
  .ring-nodes li::after {
    content: attr(data-text);
    flex: 1;
    color: var(--muted);
    font-size: 14px;
    padding-top: 4px;
  }
  .ring-nodes span {
    width: 92px;
    padding-top: 11px;
    color: var(--fg);
    white-space: normal;
  }
  .ring-nodes i {
    flex-shrink: 0;
  }
  .skill-grid,
  .pain-grid,
  .feat-grid,
  .hmi-points,
  .history-inner,
  .safety-inner {
    grid-template-columns: minmax(0, 1fr);
  }

  /* 网页 HMI：标签铺满一行；画面改成两列，第三块和趋势图占满一行 */
  .hmi-demo {
    margin-bottom: 36px;
  }
  .hmi-tabs {
    width: 100%;
    margin-bottom: 14px;
  }
  .hmi-tab {
    padding: 8px 4px;
    font-size: 13px;
  }
  .hmi-tab::after {
    left: 12px;
    right: 12px;
  }
  .hmi-frame {
    border-radius: 16px;
  }
  .hmi-head {
    gap: 10px;
    height: 42px;
    padding: 0 12px;
  }
  .hmi-head b {
    font-size: 14px;
  }
  .hmi-head .hmi-nav {
    display: none;
  }
  .hmi-alarm {
    padding: 6px 12px;
  }
  .hmi-body {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    grid-template-rows: auto auto 1fr;
    gap: 10px;
    padding: 12px;
  }
  /* 输送线：窄屏上不再等比缩小，固定高度、裁掉两端，三个分拣口仍然完整 */
  .hmi-line {
    height: 78px;
  }
  .hmi-panel {
    padding: 12px;
  }
  .hmi-panel.span-sm {
    grid-column: 1 / -1;
  }
  .hmi-tank {
    height: 128px;
  }
  .hmi-big b {
    font-size: 26px;
  }
  .hmi-kv {
    gap: 6px 10px;
  }
  .hmi-legend i {
    margin-left: 4px;
  }
  .hmi-lanes div {
    gap: 6px;
  }
  .hmi-lanes b {
    min-width: 0;
  }
  .install-row {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

/* 减少动态效果：直接显示最终状态 */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  .reveal,
  .gates li {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
    animation: none !important;
  }
  .film,
  .film-glow,
  .film-btn::after {
    animation: none !important;
  }
  .js .scrub span {
    color: var(--fg);
    transition: none;
  }
  .gates i {
    transition: none;
  }
  /* 网页 HMI：不自动轮换（脚本里也不启动），切换和数值变化不做过渡，皮带和报警灯不动 */
  .hmi-screen,
  .hmi-screen.on,
  .hmi-tab,
  .parcel,
  .hmi-fill,
  .g-val,
  .hmi-lanes em,
  .hmi-hours i,
  .hmi-meter i,
  .hmi-steps li,
  .lamp::before {
    transition: none !important;
  }
  .belt-run,
  .hmi-alarm.on::before,
  .hmi-tab::after {
    animation: none !important;
  }
}