/* ==========================================================
   上海中天科工航天科技有限公司 — 官网样式
   ========================================================== */

:root {
  /* 品牌色（取自公司标志） */
  --brand-red: #e60a16;
  --brand-red-dark: #c4000c;
  --brand-blue: #132c86;

  /* 深色区块：由品牌蓝加深 */
  --ink: #0a1433;
  --ink-2: #101c45;
  --ink-3: #172655;
  --line-dark: rgba(170, 190, 255, 0.12);
  --text-on-dark: #eef1f8;
  --muted-on-dark: #9ba6c4;

  /* 浅色区块 */
  --paper: #f2f4f8;
  --paper-2: #e3e7ef;
  --white: #ffffff;
  --text: #0e1630;
  --muted: #5a6275;
  --line: rgba(14, 22, 48, 0.12);

  /* 强调色：品牌红（深色背景上用提亮版保证对比度） */
  --laser: var(--brand-red);
  --laser-soft: #ff4d57;
  --laser-glow: rgba(230, 10, 22, 0.4);

  --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Noto Sans SC", "Source Han Sans SC", "Helvetica Neue", Arial, sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", "Cascadia Mono", Consolas, "Liberation Mono", monospace;

  --container: 75rem;
  --gutter: clamp(1rem, 4vw, 2.5rem);
  --radius: 0.375rem;
  --nav-h: 4.25rem;
}

*, *::before, *::after { box-sizing: border-box; }

/* 根字号随屏幕宽度增长，全站尺寸（rem）随之等比放大 */
html {
  font-size: clamp(16px, 0.357vw + 10.86px, 20px);
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-h);
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 1.0625rem;
  line-height: 1.7;
  color: var(--text);
  background: var(--ink);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img, svg, canvas { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
h1, h2, h3 { margin: 0; line-height: 1.2; font-weight: 700; letter-spacing: -0.01em; }
p { margin: 0; }
ol, ul { margin: 0; padding: 0; list-style: none; }

.mono { font-family: var(--font-mono); letter-spacing: 0.02em; }

.container {
  width: 100%;
  max-width: calc(var(--container) + var(--gutter) * 2);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

:focus-visible { outline: 2px solid var(--laser); outline-offset: 3px; border-radius: 2px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.625rem;
  height: 3.125rem;
  padding: 0 1.5rem;
  border-radius: var(--radius);
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  border: 1px solid transparent;
  cursor: pointer;
  font-family: inherit;
  transition: background-color .2s, border-color .2s, color .2s, transform .2s;
}
.btn svg { width: 1.125rem; height: 1.125rem; transition: transform .2s; }
.btn:hover svg { transform: translateX(3px); }
.btn--primary { background: var(--laser); color: #fff; }
.btn--primary:hover { background: var(--brand-red-dark); }
.btn--ghost { border-color: rgba(255,255,255,.28); color: var(--text-on-dark); }
.btn--ghost:hover { border-color: var(--text-on-dark); background: rgba(255,255,255,.04); }

/* ---------- 导航 ---------- */
.nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 50;
  height: var(--nav-h);
  color: var(--text);
  background: #fff;
  border-bottom: 1px solid var(--line);
  transition: box-shadow .3s;
}
.nav.is-scrolled { box-shadow: 0 0.375rem 1.5rem rgba(10, 20, 51, 0.08); }
.nav__inner { height: 100%; display: flex; align-items: center; justify-content: space-between; gap: 1.5rem; }

/* 标志中的 “ZT” 与白色条带为透明，只能放在浅色底上 */
.brand { display: flex; align-items: center; gap: 0.75rem; color: var(--text); }
.brand__mark { width: auto; height: 2.625rem; }
.brand__text { display: flex; flex-direction: column; line-height: 1.15; }
.brand__text strong { font-size: 1.25rem; font-weight: 800; letter-spacing: 0.14em; color: #000; }
.brand__text small { font-size: 0.8125rem; font-weight: 700; font-style: italic; letter-spacing: 0.12em; color: #000; }

.nav__links { display: flex; align-items: center; gap: 1.875rem; font-size: 1rem; }
.nav__links a { color: var(--muted); transition: color .2s; position: relative; }
.nav__links a:hover, .nav__links a.is-active { color: var(--brand-blue); }
.nav__links a.is-active:not(.nav__cta)::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -6px; height: 2px; background: var(--brand-red);
}
.nav__links .nav__cta {
  color: #fff;
  background: var(--brand-red);
  padding: 0.5rem 1.125rem;
  border-radius: var(--radius);
}
.nav__links .nav__cta:hover, .nav__links .nav__cta.is-active { color: #fff; }
.nav__links .nav__cta:hover { background: var(--brand-red-dark); }

.nav__toggle {
  display: none;
  width: 2.75rem; height: 2.75rem;
  background: none; border: 0; padding: 0; cursor: pointer;
  position: relative;
}
.nav__toggle span {
  position: absolute; left: 0.6875rem; right: 0.6875rem; height: 2px; background: var(--text);
  transition: transform .25s, top .25s;
}
.nav__toggle span:nth-child(1) { top: 1.0625rem; }
.nav__toggle span:nth-child(2) { top: 1.5625rem; }
.nav__toggle[aria-expanded="true"] span:nth-child(1) { top: 1.3125rem; transform: rotate(45deg); }
.nav__toggle[aria-expanded="true"] span:nth-child(2) { top: 1.3125rem; transform: rotate(-45deg); }

/* ---------- 首屏 ---------- */
.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100svh;
  padding: calc(var(--nav-h) + 4.5rem) 0 3.5rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 4rem;
  color: var(--text-on-dark);
  background:
    radial-gradient(56.25rem 32.5rem at 80% 38%, rgba(230, 10, 22, 0.10), transparent 60%),
    radial-gradient(62.5rem 43.75rem at 10% 100%, rgba(19, 44, 134, 0.45), transparent 65%),
    var(--ink);
  overflow: hidden;
}
.hero__canvas-wrap {
  position: absolute;
  top: calc(var(--nav-h) + 1.5rem);
  right: max(var(--gutter), calc((100vw - var(--container)) / 2));
  width: min(44vw, 37.5rem);
  aspect-ratio: 1;
}
.hero__canvas-wrap canvas { width: 100%; height: 100%; }
.hero__readout {
  position: absolute;
  left: 0; right: 0; bottom: -30px;
  display: flex; flex-wrap: wrap; gap: 0.375rem 1.125rem;
  font-size: 0.875rem;
  color: var(--muted-on-dark);
  letter-spacing: 0.06em;
}
.hero__readout b { color: var(--text-on-dark); font-weight: 500; }
.hero__status { margin-left: auto; display: inline-flex; align-items: center; gap: 0.4375rem; color: var(--laser-soft); }
.hero__status i {
  width: 0.375rem; height: 0.375rem; border-radius: 50%; background: var(--laser);
  box-shadow: 0 0 0.5rem var(--laser);
  animation: blink 1.4s infinite;
}
@keyframes blink { 50% { opacity: .3; } }

.hero__content { position: relative; z-index: 1; }
.hero__content > * { max-width: 37.5rem; }
.eyebrow {
  font-size: 0.8125rem;
  letter-spacing: 0.22em;
  color: var(--laser-soft);
  margin-bottom: 1.625rem;
  display: flex; align-items: center; gap: 0.75rem;
}
.eyebrow::before { content: ""; width: 1.75rem; height: 1px; background: currentColor; }
.hero__title {
  font-size: clamp(2.25rem, 5vw, 4.75rem);
  line-height: 1.12;
  letter-spacing: 0.01em;
  font-weight: 800;
}
.hero__title em {
  font-style: normal;
  color: var(--laser);
  text-shadow: 0 0 2.25rem var(--laser-glow);
}
.hero__lead {
  margin-top: 1.75rem;
  font-size: clamp(1rem, 1.3vw, 1.1875rem);
  color: var(--muted-on-dark);
  max-width: 33.75rem;
}
.hero__actions { margin-top: 2.5rem; display: flex; flex-wrap: wrap; gap: 0.875rem; }

.stats {
  position: relative; z-index: 1;
  margin: 0;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-top: 1px solid var(--line-dark);
}
.stat { padding: 1.625rem 1.5rem 0 0; }
.stat + .stat { padding-left: 1.5rem; border-left: 1px solid var(--line-dark); }
.stat dt { font-size: clamp(1.625rem, 2.8vw, 2.375rem); font-weight: 500; line-height: 1; color: var(--text-on-dark); }
.stat dt span { font-size: 0.42em; margin-left: 0.25rem; color: var(--muted-on-dark); }
.stat dd { margin: 0.625rem 0 0; font-size: 0.9375rem; color: var(--muted-on-dark); }

/* ---------- 通用区块 ---------- */
.section { padding: clamp(5rem, 11vw, 8.75rem) 0; }
.section--light { background: var(--white); color: var(--text); }
.section--paper { background: var(--paper); color: var(--text); }
.section--dark { background: var(--ink); color: var(--text-on-dark); }

.section-head { margin-bottom: clamp(2.75rem, 6vw, 4.5rem); }
.section-head h2 { font-size: clamp(1.75rem, 3.4vw, 3.125rem); letter-spacing: 0; }
.section-head--split { display: grid; grid-template-columns: 1fr 1fr; gap: 2.5rem 5rem; align-items: end; }
.section-intro { color: var(--muted); font-size: 1.0625rem; max-width: 32.5rem; }
.section--dark .section-intro { color: var(--muted-on-dark); }

.section-label {
  display: flex; align-items: center; gap: 0.875rem;
  font-size: 0.9375rem;
  letter-spacing: 0.08em;
  color: var(--muted);
  margin-bottom: 1.25rem;
}
.section--dark .section-label { color: var(--muted-on-dark); }
.section-label span { color: var(--brand-red); }
.section--dark .section-label span { color: var(--laser-soft); }
.section-label span::after { content: " /"; color: var(--line); }
.section--dark .section-label span::after { color: var(--line-dark); }

/* ---------- 两栏正文 ---------- */
.split { display: grid; grid-template-columns: 5fr 7fr; gap: 2.5rem 5rem; }
.split .section-head { margin-bottom: 0; }
.lead-text { font-size: clamp(1.125rem, 1.5vw, 1.3125rem); line-height: 1.9; color: var(--text); }
.prose p + p { margin-top: 1.125rem; }
.prose p:not(.lead-text) { color: var(--muted); }

.more-link {
  display: inline-flex; align-items: center; gap: 0.5rem;
  margin-top: 1.75rem;
  font-weight: 600; font-size: 1rem;
  color: var(--brand-blue);
  border-bottom: 1px solid currentColor;
  padding-bottom: 0.25rem;
}
.more-link svg { width: 1rem; height: 1rem; transition: transform .2s; }
.more-link:hover { color: var(--brand-red); }
.more-link:hover svg { transform: translateX(3px); }
.section--dark .more-link { color: var(--text-on-dark); }
.section--dark .more-link:hover { color: var(--laser-soft); }
.more-link--end { justify-self: end; margin-top: 0; }

.fine-print { margin-top: 1.75rem; font-size: 0.9375rem; color: var(--muted-on-dark); }

/* ---------- 特点三栏 ---------- */
.pillars { display: grid; grid-template-columns: repeat(3, 1fr); gap: 0; border-top: 1px solid var(--line); }
.pillar { padding: 2rem 2.5rem 0 0; }
.pillar p { max-width: 21.25rem; }
.pillar + .pillar { padding-left: 2.5rem; border-left: 1px solid var(--line); }
.pillar__no { font-size: 0.8125rem; color: var(--laser); }
.pillar h3 { margin: 0.625rem 0 0.625rem; font-size: 1.1875rem; }
.pillar p { font-size: 1rem; color: var(--muted); }

/* ---------- 工艺流程 ---------- */
.process {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid var(--line-dark);
  border-left: 1px solid var(--line-dark);
  counter-reset: step;
}
.process__step {
  position: relative;
  padding: 2rem 1.875rem 2.25rem;
  border-right: 1px solid var(--line-dark);
  border-bottom: 1px solid var(--line-dark);
  transition: background-color .3s;
}
.process__step::before {
  content: ""; position: absolute; left: -1px; top: -1px; width: 0; height: 2px; background: var(--laser);
  transition: width .5s ease;
}
.process__step:hover { background: var(--ink-2); }
.process__step:hover::before { width: calc(100% + 1px); }
.process__no { font-size: 0.875rem; color: var(--laser-soft); }
.process__step h3 { margin: 1.125rem 0 0.75rem; font-size: 1.25rem; }
.process__step p { font-size: 1rem; color: var(--muted-on-dark); }
.process--4 { grid-template-columns: repeat(4, 1fr); }
.process--5 { grid-template-columns: repeat(5, 1fr); }
.process--5 .process__step { padding: 1.75rem 1.375rem 1.875rem; }

/* ---------- 技术优势 / 设计须知 ---------- */
.benefits { display: grid; grid-template-columns: repeat(3, 1fr); gap: 0; border-top: 1px solid var(--line); }
.benefits li {
  padding: 1.75rem 2rem 2rem 0;
  border-bottom: 1px solid var(--line);
  font-size: 1rem; color: var(--muted);
}
.benefits li:not(:nth-child(3n+1)) { padding-left: 2rem; border-left: 1px solid var(--line); }
.benefits b, .notes b { display: block; color: var(--text); font-size: 1.1875rem; font-weight: 700; margin-bottom: 0.5rem; }
.benefits b::before {
  content: ""; display: block; width: 1.375rem; height: 3px; background: var(--brand-red); margin-bottom: 1.125rem;
}
.notes { margin-top: 2rem; display: grid; gap: 0; border-top: 1px solid var(--line); }
.notes li { padding: 1.25rem 0 1.25rem 1.875rem; border-bottom: 1px solid var(--line); font-size: 1rem; color: var(--muted); position: relative; }
.notes li::before {
  content: "!"; position: absolute; left: 0; top: 1.5rem;
  width: 1.125rem; height: 1.125rem; border-radius: 50%;
  background: var(--brand-blue); color: #fff;
  font: 700 0.75rem/1.125rem var(--font-sans); text-align: center;
}
.notes b { font-size: 1.0625rem; margin-bottom: 0.25rem; }

/* ---------- 设备示意图 ---------- */
.schematic { display: grid; grid-template-columns: 7fr 5fr; gap: 2.5rem 4rem; align-items: center; }
.schematic__figure {
  margin: 0;
  background: var(--ink);
  background-image:
    linear-gradient(var(--line-dark) 1px, transparent 1px),
    linear-gradient(90deg, var(--line-dark) 1px, transparent 1px);
  background-size: 1.5rem 1.5rem;
  border-radius: var(--radius);
  padding: clamp(1.25rem, 3vw, 2.25rem);
}
.schematic__figure svg { width: 100%; height: auto; }
.schematic__figure figcaption { margin-top: 1rem; font-size: 0.8125rem; letter-spacing: 0.14em; color: var(--muted-on-dark); }
.s-box { fill: var(--ink-3); stroke: #8f9bc2; stroke-width: 1.2; }
.s-text { fill: var(--text-on-dark); font: 500 15px var(--font-sans); }
.s-small { fill: var(--muted-on-dark); font: 13px var(--font-sans); }
.s-beam { stroke: var(--laser-soft); stroke-width: 2.4; fill: none; filter: drop-shadow(0 0 3px var(--laser-glow)); }
.s-fan { stroke: var(--laser-soft); stroke-width: 1; stroke-dasharray: 4 4; opacity: .45; fill: none; }
.s-mirror { fill: #c9d1e8; }
.s-lens { fill: rgba(143, 155, 194, .25); stroke: #c9d1e8; stroke-width: 1.2; }
.s-wall { fill: none; stroke: #8f9bc2; stroke-width: 2; }
.s-window { stroke: #8f9bc2; stroke-width: 2; stroke-dasharray: 3 4; }
.s-gas { fill: none; stroke: #6f8de0; stroke-width: 1.6; }
.s-dot { fill: #56607d; }
.s-piston { fill: #3a4668; }
.s-rod { stroke: #3a4668; stroke-width: 6; }
.s-part { fill: #8d95a8; }
.s-blade { fill: #c9d1e8; }
.s-arrow { fill: none; stroke: #c9d1e8; stroke-width: 1.6; }
.s-callout circle { fill: var(--brand-red); }
.s-callout text { fill: #fff; font: 700 12px var(--font-mono); text-anchor: middle; }

.legend { counter-reset: lg; display: grid; gap: 0; border-top: 1px solid var(--line); }
.legend li {
  counter-increment: lg;
  position: relative;
  padding: 0.8125rem 0 0.8125rem 2.5rem;
  border-bottom: 1px solid var(--line);
  font-size: 0.9375rem; color: var(--muted);
}
.legend li::before {
  content: counter(lg);
  position: absolute; left: 0; top: 0.8125rem;
  width: 1.375rem; height: 1.375rem; border-radius: 50%;
  background: var(--brand-red); color: #fff;
  font: 700 0.75rem/1.375rem var(--font-mono); text-align: center;
}
.legend b { color: var(--text); font-weight: 600; margin-right: 0.625rem; }

/* ---------- 服务 ---------- */
.services { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.25rem; }
.service {
  display: block;
  color: inherit;
  padding: 2.125rem 1.875rem 2.25rem;
  background: var(--paper);
  border: 1px solid transparent;
  border-radius: var(--radius);
  transition: border-color .25s, transform .25s, background-color .25s;
}
.service:hover { border-color: rgba(19, 44, 134, 0.25); background: #fff; transform: translateY(-3px); }
.service__icon { width: 2.75rem; height: 2.75rem; fill: none; stroke: var(--brand-blue); stroke-width: 1.6; stroke-linejoin: round; stroke-linecap: round; }
.service__icon .hl { stroke: var(--laser); stroke-width: 2.2; }
.service h3 { margin: 1.5rem 0 0.625rem; font-size: 1.25rem; }
.service p { font-size: 1rem; color: var(--muted); }
.section--paper .service { background: var(--white); }

/* 服务详情 */
.svc-list { display: grid; grid-template-columns: 1fr 1fr; gap: 0 4rem; border-top: 1px solid var(--line); }
.svc {
  display: grid; grid-template-columns: 2.75rem 1fr; gap: 1.5rem;
  padding: 2.5rem 0;
  border-bottom: 1px solid var(--line);
  scroll-margin-top: calc(var(--nav-h) + 1.5rem);
}
.svc h3 { font-size: 1.375rem; margin-bottom: 0.625rem; }
.svc p { color: var(--muted); font-size: 1rem; }
.svc ul { margin-top: 1rem; display: grid; gap: 0.5rem; }
.svc li { position: relative; padding-left: 1.125rem; font-size: 1rem; }
.svc li::before { content: ""; position: absolute; left: 0; top: .75em; width: 0.5rem; height: 2px; background: var(--brand-red); }

/* ---------- 应用 ---------- */
.apps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.25rem; }
.app {
  display: flex; flex-direction: column;
  background: var(--white);
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--line);
}
.app--feature { grid-column: 1 / -1; flex-direction: row; }
.app__art {
  position: relative;
  background: var(--ink);
  aspect-ratio: 16 / 10;
  overflow: hidden;
}
.app__art img {
  position: absolute; inset: 0;
  width: 100%; height: 100%;
  object-fit: cover;
  transition: transform .6s ease;
}
.app:hover .app__art img { transform: scale(1.04); }
.app--feature .app__art { flex: 0 0 55%; aspect-ratio: auto; min-height: 20rem; }
.app__body { padding: 1.625rem 1.625rem 1.875rem; }
.app--feature .app__body { padding: clamp(1.75rem, 4vw, 3.5rem); display: flex; flex-direction: column; justify-content: center; }
.app__tag { font-size: 0.8125rem; letter-spacing: 0.2em; color: var(--brand-blue); font-weight: 600; }
.app h3 { margin: 0.625rem 0 0.625rem; font-size: 1.3125rem; }
.app--feature h3 { font-size: clamp(1.5rem, 2.4vw, 2rem); }
.app p { font-size: 1rem; color: var(--muted); }
.app--feature p { font-size: 1.0625rem; max-width: 27.5rem; }
.app { scroll-margin-top: calc(var(--nav-h) + 1.5rem); }
.app__list { margin-top: 1rem; display: grid; gap: 0.375rem; font-size: 0.9375rem; color: var(--text); }
.app__list li { position: relative; padding-left: 1rem; }
.app__list li::before { content: ""; position: absolute; left: 0; top: .75em; width: 0.4375rem; height: 2px; background: var(--brand-red); }

.img-credit { margin-top: 1rem; font-size: 0.8125rem; color: var(--muted); }
.section--dark .img-credit { color: var(--muted-on-dark); }

/* 首页应用磁贴 */
.app-tiles { display: grid; grid-template-columns: repeat(5, 1fr); border-top: 1px solid var(--line-dark); border-left: 1px solid var(--line-dark); }
.app-tiles a {
  position: relative;
  display: flex; flex-direction: column; justify-content: flex-end; gap: 0.375rem;
  min-height: 15rem;
  padding: 1.625rem 1.5rem;
  overflow: hidden;
  border-right: 1px solid var(--line-dark);
  border-bottom: 1px solid var(--line-dark);
  color: #fff;
}
.app-tiles img {
  position: absolute; inset: 0;
  width: 100%; height: 100%;
  object-fit: cover;
  opacity: .6;
  transition: transform .6s ease, opacity .3s;
}
.app-tiles a::before {
  content: ""; position: absolute; inset: 0; z-index: 1;
  background: linear-gradient(to top, rgba(10, 20, 51, 0.95) 15%, rgba(10, 20, 51, 0.25) 75%);
}

.app-tiles a:hover img { opacity: .85; transform: scale(1.05); }

.app-tiles span, .app-tiles b { position: relative; z-index: 2; }
.app-tiles span { font-size: 0.875rem; font-weight: 500; letter-spacing: 0.18em; color: var(--laser-soft); }
.app-tiles b { font-size: 1.5rem; font-weight: 700; }

/* ---------- 材料 ---------- */
.materials { border-top: 1px solid var(--line); }
.materials__row {
  display: grid;
  grid-template-columns: 1.1fr 1.5fr 1.5fr 1.3fr;
  gap: 1.5rem;
  padding: 1.375rem 0.75rem;
  border-bottom: 1px solid var(--line);
  font-size: 1rem;
  color: var(--muted);
  align-items: center;
  transition: background-color .2s;
}
.materials__row:not(.materials__row--head):hover { background: var(--paper); }
.materials__row--head { font-size: 0.8125rem; letter-spacing: 0.16em; padding: 1rem 0.75rem; }
.materials__row span.mono { color: var(--text); font-size: 0.9375rem; }
.materials__name { display: flex; align-items: center; gap: 0.875rem; color: var(--text); font-weight: 600; font-size: 1.0625rem; }
.el {
  font-style: normal;
  width: 2.25rem; height: 2.25rem;
  display: inline-grid; place-items: center;
  border: 1px solid rgba(230, 10, 22, .45);
  color: var(--brand-red);
  font-size: 0.875rem;
  font-weight: 500;
  border-radius: 3px;
  flex: none;
}
.section--dark .el { border-color: rgba(255, 77, 87, .55); color: var(--laser-soft); }

/* 首页材料条 */
.el-strip { display: grid; grid-template-columns: repeat(7, 1fr); gap: 0.75rem; }
.el-strip li {
  display: flex; flex-direction: column; align-items: flex-start; gap: 0.875rem;
  padding: 1.375rem 1.125rem;
  background: var(--paper);
  border-radius: var(--radius);
  font-size: 1rem; font-weight: 600;
}
.el-strip .el { width: 2.75rem; height: 2.75rem; font-size: 1rem; background: var(--white); }

/* ---------- 联系 ---------- */
.flow {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  margin-bottom: 3.5rem;
  font-size: 0.9375rem;
  font-family: var(--font-sans);
}
.flow li {
  position: relative;
  padding: 1rem 1rem 0 0;
  border-top: 2px solid var(--paper-2);
  color: var(--text);
  font-weight: 600;
}
.flow li:first-child { border-top-color: var(--laser); }
.flow li span { display: block; font-family: var(--font-mono); font-size: 0.8125rem; color: var(--brand-blue); font-weight: 400; margin-bottom: 0.25rem; }

.contact { display: grid; grid-template-columns: 4fr 7fr; gap: 2.5rem 5rem; }
.contact__info dl { margin: 0; }
.contact__info dl > div { padding: 1.125rem 0; border-bottom: 1px solid var(--line); }
.contact__info dl > div:first-child { border-top: 1px solid var(--line); }
.contact__info dt { font-size: 0.8125rem; letter-spacing: 0.16em; color: var(--muted); }
.contact__info dd { margin: 0.25rem 0 0; font-size: 1.0625rem; font-weight: 500; }
.contact__info dd a:hover { color: var(--laser); }
.contact__note { margin-top: 1.5rem; font-size: 0.9375rem; color: var(--muted); }
.contact__title { font-size: 1.5rem; margin-bottom: 1.5rem; }

.form { background: var(--paper); border-radius: var(--radius); padding: clamp(1.5rem, 3.5vw, 2.5rem); }
.form__grid { display: grid; grid-template-columns: 1fr 1fr; gap: 1.125rem 1.25rem; }
.field { display: flex; flex-direction: column; gap: 0.5rem; font-size: 0.9375rem; color: var(--muted); }
.field--full { grid-column: 1 / -1; }
.field em { color: var(--laser); font-style: normal; }
.field input, .field select, .field textarea {
  font: inherit;
  font-size: 1rem;
  color: var(--text);
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 0.25rem;
  padding: 0.75rem 0.875rem;
  width: 100%;
  transition: border-color .2s, box-shadow .2s;
}
.field textarea { resize: vertical; min-height: 7.5rem; }
.field input:focus, .field select:focus, .field textarea:focus {
  outline: none;
  border-color: var(--brand-blue);
  box-shadow: 0 0 0 3px rgba(19, 44, 134, .15);
}
.field.is-invalid input, .field.is-invalid textarea { border-color: #d23a2a; }
.form__foot { margin-top: 1.625rem; display: flex; align-items: center; flex-wrap: wrap; gap: 1rem 1.5rem; }
.form__msg { font-size: 0.9375rem; color: var(--muted); }
.form__msg.is-error { color: #c0341f; }

/* ---------- 子页面页首横幅 ---------- */
.page-hero {
  position: relative;
  padding: calc(var(--nav-h) + clamp(3.5rem, 8vw, 6rem)) 0 clamp(3.5rem, 7vw, 5.5rem);
  color: var(--text-on-dark);
  background:
    radial-gradient(43.75rem 25rem at 85% 20%, rgba(230, 10, 22, 0.12), transparent 60%),
    radial-gradient(56.25rem 37.5rem at 0% 100%, rgba(19, 44, 134, 0.5), transparent 65%),
    var(--ink);
  overflow: hidden;
}
/* 右侧斜向扫描线：呼应 SLM 逐层扫描 */
.page-hero::after {
  content: "";
  position: absolute; top: 0; right: 0; bottom: 0;
  width: min(48%, 38.75rem);
  background: repeating-linear-gradient(-23deg, transparent 0 0.6875rem, rgba(170, 190, 255, 0.10) 0.6875rem 0.75rem);
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 60%);
  mask-image: linear-gradient(90deg, transparent, #000 60%);
  pointer-events: none;
}
.page-hero .container { position: relative; z-index: 1; }
.page-hero h1 { font-size: clamp(2.25rem, 5vw, 3.75rem); font-weight: 800; }
.page-hero__lead { margin-top: 1.125rem; max-width: 35rem; font-size: clamp(1rem, 1.4vw, 1.25rem); color: var(--muted-on-dark); }
.breadcrumb { display: flex; gap: 0.625rem; font-size: 0.8125rem; letter-spacing: 0.1em; color: var(--muted-on-dark); margin-bottom: 2.25rem; }
.breadcrumb a:hover { color: var(--text-on-dark); }
.breadcrumb span { opacity: .5; }

/* ---------- 底部咨询条 ---------- */
.cta-band { background: var(--brand-blue); color: #fff; padding: clamp(3rem, 6vw, 4.5rem) 0; position: relative; overflow: hidden; }
.cta-band::before {
  content: ""; position: absolute; inset: 0;
  background: repeating-linear-gradient(-23deg, transparent 0 0.6875rem, rgba(255, 255, 255, 0.05) 0.6875rem 0.75rem);
}
.cta-band__inner { position: relative; display: flex; align-items: center; justify-content: space-between; gap: 1.5rem 3rem; flex-wrap: wrap; }
.cta-band__eyebrow { font-size: 0.8125rem; letter-spacing: 0.2em; color: rgba(255, 255, 255, 0.6); margin-bottom: 0.625rem; }
.cta-band h2 { font-size: clamp(1.625rem, 3vw, 2.25rem); }
.cta-band p:not(.cta-band__eyebrow) { margin-top: 0.625rem; color: rgba(255, 255, 255, 0.75); max-width: 35rem; }

/* ---------- 页脚 ---------- */
.footer { background: var(--ink); color: var(--muted-on-dark); padding: 4rem 0 2rem; font-size: 0.9375rem; }
.footer__inner { display: flex; justify-content: space-between; align-items: flex-start; gap: 2rem; flex-wrap: wrap; padding-bottom: 2.5rem; border-bottom: 1px solid var(--line-dark); }
.footer__brand { display: flex; align-items: center; gap: 1rem; }
.footer__brand > div { display: flex; flex-direction: column; gap: 0.375rem; }
.footer__logo { flex: none; display: grid; place-items: center; width: 3.5rem; height: 3.5rem; background: #fff; border-radius: var(--radius); }
.footer__logo img { height: 2.5rem; width: auto; }
.footer__brand strong { color: var(--text-on-dark); font-size: 1.125rem; letter-spacing: 0.04em; }
.footer__brand span { font-size: 0.8125rem; letter-spacing: 0.12em; }
.footer__links { display: flex; flex-wrap: wrap; gap: 0.75rem 1.75rem; }
.footer__links a:hover, .footer__legal a:hover { color: var(--text-on-dark); }
.footer__legal { padding-top: 1.5rem; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 0.5rem 1.5rem; font-size: 0.875rem; }

/* ---------- 入场动效 ---------- */
.reveal { opacity: 0; transform: translateY(1.125rem); transition: opacity .7s ease, transform .7s ease; }
.reveal.is-visible { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
}

/* ==========================================================
   响应式
   ========================================================== */
@media (max-width: 1080px) {
  .nav__links { gap: 1.375rem; font-size: 0.9375rem; }
  .hero__canvas-wrap { opacity: .45; width: min(70vw, 35rem); right: -60px; }
  .apps { grid-template-columns: repeat(2, 1fr); }
  .services { grid-template-columns: repeat(2, 1fr); }
  .split, .schematic { grid-template-columns: 1fr; }
  .process--4 { grid-template-columns: repeat(2, 1fr); }
  .process--5 { grid-template-columns: repeat(3, 1fr); }
  .benefits { grid-template-columns: 1fr 1fr; }
  .benefits li:not(:nth-child(3n+1)) { padding-left: 0; border-left: 0; }
  .benefits li:nth-child(even) { padding-left: 2rem; border-left: 1px solid var(--line); }
}

@media (max-width: 880px) {
  .nav__toggle { display: block; }
  .nav__links {
    position: fixed;
    top: var(--nav-h); left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    padding: 0.5rem var(--gutter) 1.5rem;
    background: #fff;
    border-bottom: 1px solid var(--line);
    box-shadow: 0 1rem 2rem rgba(10, 20, 51, 0.12);
    transform: translateY(-8px);
    opacity: 0; visibility: hidden;
    transition: opacity .25s, transform .25s, visibility .25s;
  }
  .nav.is-open .nav__links { opacity: 1; visibility: visible; transform: none; }
  .nav__links a { padding: 0.875rem 0; border-bottom: 1px solid var(--line); font-size: 1.0625rem; color: var(--text); }
  .nav__links a.is-active:not(.nav__cta) { color: var(--brand-red); }
  .nav__links a.is-active:not(.nav__cta)::after { display: none; }
  .nav__links .nav__cta { margin-top: 1rem; padding: 0.8125rem 0; text-align: center; border-bottom: 0; }

  .section-head--split { grid-template-columns: 1fr; gap: 1.25rem; }
  .process, .process--5 { grid-template-columns: repeat(2, 1fr); }
  .svc-list { grid-template-columns: 1fr; }
  .app-tiles { grid-template-columns: 1fr 1fr; }
  .app-tiles li:last-child { grid-column: 1 / -1; }
  .el-strip { grid-template-columns: repeat(4, 1fr); }
  .more-link--end { justify-self: start; }
  .app--feature { flex-direction: column; }
  .app--feature .app__art { flex: none; min-height: 0; aspect-ratio: 16 / 10; }
  .contact { grid-template-columns: 1fr; }
  .flow { grid-template-columns: repeat(5, minmax(0, 1fr)); font-size: 0.875rem; }

  .materials__row--head { display: none; }
  .materials__row { grid-template-columns: 1fr 1fr; gap: 0.375rem 1.25rem; padding: 1.25rem 0; }
  .materials__name { grid-column: 1 / -1; margin-bottom: 0.5rem; }
  .materials__row span:nth-child(2) { grid-column: 1 / -1; }
}

@media (max-width: 640px) {
  .hero { padding-top: calc(var(--nav-h) + 2.5rem); gap: 3rem; }
  .hero__canvas-wrap { width: 120vw; right: -40vw; top: 1.25rem; opacity: .22; }
  .hero__readout { display: none; }
  .hero .eyebrow { letter-spacing: 0.1em; }
  .stats { grid-template-columns: 1fr 1fr; }
  .stat, .stat + .stat { padding: 1.25rem 0.75rem 1.25rem 0; border-left: 0; }
  .stat:nth-child(even) { padding-left: 1rem; border-left: 1px solid var(--line-dark); }
  .stat:nth-child(n+3) { border-top: 1px solid var(--line-dark); }

  .pillars { grid-template-columns: 1fr; }
  .pillar, .pillar + .pillar { padding: 1.375rem 0; border-left: 0; border-bottom: 1px solid var(--line); }
  .process, .process--4, .process--5 { grid-template-columns: 1fr; }
  .process__step, .process--5 .process__step { padding: 1.625rem 1.375rem 1.75rem; }
  .benefits { grid-template-columns: 1fr; }
  .benefits li:nth-child(even) { padding-left: 0; border-left: 0; }
  .app-tiles a { min-height: 10rem; padding: 1.25rem 1.125rem; }
  .app-tiles b { font-size: 1.1875rem; }
  .el-strip { grid-template-columns: repeat(3, 1fr); gap: 0.5rem; }
  .el-strip li { padding: 1rem 0.75rem; font-size: 0.9375rem; }
  .svc { grid-template-columns: 1fr; gap: 1rem; padding: 2rem 0; }
  .page-hero::after { width: 70%; opacity: .6; }
  .services, .apps { grid-template-columns: 1fr; }
  .flow { grid-template-columns: 1fr; gap: 0; }
  .flow li { border-top: 0; border-left: 2px solid var(--paper-2); padding: 0.5rem 0 0.5rem 1rem; display: flex; gap: 0.75rem; align-items: baseline; }
  .flow li:first-child { border-left-color: var(--laser); }
  .flow li span { margin: 0; }
  .form__grid { grid-template-columns: 1fr; }
  .form__foot .btn { width: 100%; justify-content: center; }
  .materials__row { grid-template-columns: 1fr; }
  .footer__legal { flex-direction: column; }
}