:root {
  --rail-width: 118px;
  --notice-height: 34px;
  --ink: #111318;
  --muted: #606a73;
  --paper: #f5f6f1;
  --white: #ffffff;
  --line: #d9ddd2;
  --night: #05070b;
  --deep: #111821;
  --cyan: #76dbff;
  --amber: #d9a247;
  --jade: #55ad82;
  --clay: #8d6c52;
  --footer: #171913;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  letter-spacing: 0;
}

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

.notice-bar {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 45;
  min-height: var(--notice-height);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 7px 18px;
  background: #0e1415;
  color: rgba(255, 255, 255, 0.78);
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 13px;
  line-height: 1.5;
  text-align: center;
}

.site-rail {
  position: fixed;
  inset: var(--notice-height) auto 0 0;
  z-index: 20;
  width: var(--rail-width);
  background: rgba(7, 10, 13, 0.78);
  border-right: 1px solid rgba(255, 255, 255, 0.12);
  color: var(--white);
  display: flex;
  flex-direction: column;
  align-items: center;
  backdrop-filter: blur(18px);
}

.rail-logo {
  width: 100%;
  min-height: 126px;
  display: grid;
  place-items: center;
  gap: 8px;
  padding-top: 26px;
}

.logo-mark {
  width: 68px;
  height: 68px;
  display: block;
  object-fit: cover;
  padding: 4px;
  border-radius: 10px;
  background: var(--white);
  box-shadow: 0 12px 28px rgba(0, 0, 0, 0.24);
}

.rail-logo small {
  color: rgba(255, 255, 255, 0.68);
  font-size: 11px;
}

.rail-nav {
  width: 100%;
  margin-top: 22px;
}

.rail-nav a {
  position: relative;
  display: block;
  height: 52px;
  line-height: 52px;
  text-align: center;
  color: rgba(255, 255, 255, 0.76);
  font-size: 14px;
  font-weight: 650;
  transition:
    color 180ms ease,
    background 180ms ease;
}

.rail-nav a::before {
  content: "";
  position: absolute;
  inset: 0 auto 0 0;
  width: 3px;
  background: transparent;
}

.rail-nav a:hover,
.rail-nav a.active {
  color: var(--cyan);
  background: rgba(255, 255, 255, 0.04);
}

.rail-nav a.active::before {
  background: var(--cyan);
}

.rail-lang {
  margin-top: auto;
  margin-bottom: 28px;
  color: rgba(255, 255, 255, 0.58);
  font-size: 12px;
}

.mobile-bar,
.mobile-menu {
  display: none;
}

.page {
  margin-left: var(--rail-width);
  padding-top: var(--notice-height);
}

.hero {
  position: relative;
  min-height: calc(94svh - var(--notice-height));
  overflow: hidden;
  color: var(--white);
  background: var(--night);
  display: flex;
  align-items: center;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
  background:
    linear-gradient(90deg, rgba(4, 6, 9, 0.96) 0%, rgba(4, 6, 9, 0.78) 40%, rgba(4, 6, 9, 0.18) 100%),
    linear-gradient(180deg, rgba(4, 6, 9, 0.08) 0%, rgba(4, 6, 9, 0.9) 100%),
    url("./assets/qiming-simulation-hero.png") center / cover no-repeat;
  transform: scale(1.02);
}

.particle-canvas {
  position: absolute;
  inset: 0;
  z-index: 1;
  width: 100%;
  height: 100%;
  opacity: 0.86;
  pointer-events: none;
  mix-blend-mode: screen;
}

.hero-copy {
  position: relative;
  z-index: 2;
  width: min(860px, calc(100% - 96px));
  margin-left: 72px;
  padding: 92px 0 116px;
}

.eyebrow,
.section-kicker {
  margin: 0 0 18px;
  color: var(--cyan);
  font-size: 13px;
  font-weight: 760;
}

.hero h1 {
  margin: 0;
  font-size: clamp(46px, 4.1vw, 56px);
  line-height: 1.12;
  font-weight: 820;
  max-width: 860px;
  text-wrap: balance;
}

.hero h1 .line {
  display: block;
  white-space: nowrap;
}

.dynamic-heading {
  transition:
    color 420ms ease,
    filter 420ms ease,
    font-weight 420ms ease,
    transform 420ms ease,
    letter-spacing 420ms ease;
  will-change: transform, font-weight, color;
}

.section-observed h2.dynamic-heading {
  color: color-mix(in srgb, var(--ink) 92%, var(--cyan));
}

.section-observed.is-visible h2.dynamic-heading {
  color: color-mix(in srgb, var(--ink) 74%, var(--jade));
}

.architecture h2.dynamic-heading,
.boundary h2.dynamic-heading,
.contact h2.dynamic-heading {
  color: rgba(255, 255, 255, 0.94);
}

.architecture.is-visible h2.dynamic-heading,
.boundary.is-visible h2.dynamic-heading,
.contact.is-visible h2.dynamic-heading {
  color: color-mix(in srgb, var(--white) 82%, var(--cyan));
}

.hero-lead {
  margin: 28px 0 0;
  color: rgba(255, 255, 255, 0.78);
  font-size: 19px;
  line-height: 1.82;
  max-width: 650px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 38px;
}

.primary-link,
.secondary-link {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 4px;
  padding: 0 22px;
  font-size: 15px;
  font-weight: 760;
}

.primary-link {
  background: var(--white);
  color: var(--ink);
}

.secondary-link {
  border: 1px solid rgba(255, 255, 255, 0.36);
  color: var(--white);
}

.hero-status {
  position: absolute;
  z-index: 2;
  right: 34px;
  bottom: 30px;
  display: flex;
  gap: 12px;
  color: rgba(255, 255, 255, 0.64);
  font-size: 12px;
}

.hero-status span {
  border-left: 2px solid rgba(118, 219, 255, 0.7);
  padding-left: 10px;
}

.intro,
.quality,
.clients {
  padding: 108px 72px;
  background: var(--paper);
}

.intro-grid,
.clients-grid {
  display: grid;
  grid-template-columns: minmax(280px, 0.88fr) minmax(360px, 1.12fr);
  gap: 58px;
  align-items: start;
}

h2 {
  margin: 0;
  font-size: 44px;
  line-height: 1.18;
  font-weight: 760;
}

.intro-copy p,
.architecture p,
.history-head p,
.contact-copy p,
.clients-grid p {
  margin: 22px 0 0;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.85;
}

.metrics,
.client-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.metrics article,
.quality-grid article,
.client-list article {
  min-height: 238px;
  padding: 28px 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--white);
}

.metrics strong {
  color: var(--amber);
  font-size: 28px;
}

.metrics h3,
.quality-grid h3,
.client-list h3,
.process-step h3 {
  margin: 28px 0 12px;
  font-size: 22px;
  line-height: 1.35;
}

.metrics p,
.quality-grid p,
.client-list p,
.process-step p,
.contact-lines p,
.boundary-list p {
  margin: 0;
  color: var(--muted);
  font-size: 15px;
  line-height: 1.75;
}

.architecture {
  padding: 118px 72px;
  background: var(--deep);
  color: var(--white);
}

.architecture-inner {
  display: grid;
  grid-template-columns: minmax(280px, 0.9fr) minmax(380px, 1.1fr);
  gap: 70px;
  align-items: center;
}

.architecture .section-kicker,
.boundary .section-kicker {
  color: #8de4b6;
}

.architecture p {
  color: rgba(255, 255, 255, 0.68);
}

.process-list {
  border-top: 1px solid rgba(255, 255, 255, 0.14);
}

.process-step {
  display: grid;
  grid-template-columns: 74px 1fr;
  gap: 24px;
  padding: 24px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.14);
}

.process-step > span {
  color: var(--cyan);
  font-size: 22px;
  font-weight: 780;
}

.process-step h3 {
  margin-top: 0;
}

.process-step p {
  color: rgba(255, 255, 255, 0.72);
}

.history-head {
  display: grid;
  grid-template-columns: minmax(280px, 0.95fr) minmax(280px, 0.65fr);
  gap: 70px;
  align-items: end;
  margin-bottom: 58px;
}

.quality-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.quality-grid article {
  min-height: 0;
}

.quality-grid h3,
.client-list h3 {
  margin-top: 0;
}

.boundary {
  padding: 100px 72px;
  background: #16211c;
  color: var(--white);
}

.boundary-inner {
  display: grid;
  grid-template-columns: minmax(300px, 0.8fr) minmax(360px, 1.2fr);
  gap: 70px;
  align-items: start;
}

.boundary-list {
  border-top: 1px solid rgba(255, 255, 255, 0.16);
}

.boundary-list p {
  display: grid;
  grid-template-columns: 70px 1fr;
  gap: 22px;
  padding: 18px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.16);
  color: rgba(255, 255, 255, 0.76);
}

.boundary-list span {
  color: var(--amber);
  font-weight: 780;
}

.clients {
  background: #ffffff;
}

.client-list {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.contact {
  display: grid;
  grid-template-columns: minmax(320px, 0.9fr) minmax(320px, 1fr);
  gap: 70px;
  padding: 82px 72px;
  background: var(--footer);
  color: var(--white);
}

.contact .section-kicker {
  color: var(--amber);
}

.contact-copy p {
  color: rgba(255, 255, 255, 0.66);
}

.contact-lines {
  align-self: end;
  border-top: 1px solid rgba(255, 255, 255, 0.16);
}

.contact-lines p {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 18px;
  padding: 18px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.16);
  color: rgba(255, 255, 255, 0.76);
}

.contact-lines span {
  color: rgba(255, 255, 255, 0.48);
}

@media (max-width: 1180px) {
  .hero-copy,
  .intro,
  .architecture,
  .quality,
  .boundary,
  .clients,
  .contact {
    padding-left: 46px;
    padding-right: 46px;
  }

  .hero-copy {
    margin-left: 0;
  }

  .hero h1 {
    font-size: clamp(41px, 4.4vw, 48px);
  }

  h2 {
    font-size: 36px;
  }

  .intro-grid,
  .architecture-inner,
  .history-head,
  .boundary-inner,
  .clients-grid,
  .contact {
    grid-template-columns: 1fr;
  }

  .metrics,
  .quality-grid,
  .client-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  :root {
    --notice-height: 50px;
  }

  .site-rail {
    display: none;
  }

  .page {
    margin-left: 0;
  }

  .notice-bar {
    justify-content: flex-start;
    padding: 7px 14px;
    font-size: 12px;
  }

  .mobile-bar {
    position: fixed;
    inset: var(--notice-height) 0 auto;
    z-index: 40;
    height: 58px;
    padding: 0 18px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    background: rgba(6, 8, 13, 0.74);
    color: var(--white);
    backdrop-filter: blur(18px);
  }

  .mobile-logo {
    display: inline-flex;
    align-items: center;
    width: 124px;
    height: 40px;
    padding: 4px 6px;
    border-radius: 6px;
    background: var(--white);
    overflow: hidden;
  }

  .mobile-logo img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: contain;
  }

  .menu-button {
    width: 40px;
    height: 40px;
    border: 0;
    background: transparent;
    display: grid;
    place-items: center;
    padding: 0;
  }

  .menu-button span {
    width: 23px;
    height: 2px;
    background: var(--white);
    transition: transform 180ms ease;
  }

  .menu-button[aria-expanded="true"] span:first-child {
    transform: translateY(5px) rotate(45deg);
  }

  .menu-button[aria-expanded="true"] span:last-child {
    transform: translateY(-5px) rotate(-45deg);
  }

  .mobile-menu {
    position: fixed;
    inset: calc(var(--notice-height) + 58px) 0 auto;
    z-index: 35;
    display: grid;
    background: rgba(6, 8, 13, 0.94);
    color: var(--white);
    transform: translateY(-125%);
    transition: transform 180ms ease;
  }

  .mobile-menu.open {
    transform: translateY(0);
  }

  .mobile-menu a {
    padding: 16px 22px;
    border-top: 1px solid rgba(255, 255, 255, 0.12);
  }

  .hero {
    min-height: calc(92svh - var(--notice-height));
    align-items: flex-end;
  }

  .hero-bg {
    background:
      linear-gradient(180deg, rgba(4, 6, 9, 0.3) 0%, rgba(4, 6, 9, 0.94) 70%),
      url("./assets/qiming-simulation-hero.png") 62% center / cover no-repeat;
  }

  .hero-copy {
    width: 100%;
    padding: 116px 22px 78px;
  }

  .eyebrow,
  .section-kicker {
    font-size: 12px;
  }

  .hero h1 {
    font-size: 34px;
    line-height: 1.14;
  }

  .hero h1 .line {
    display: inline;
    white-space: normal;
  }

  .hero-lead {
    font-size: 16px;
    line-height: 1.75;
  }

  .hero-status {
    display: none;
  }

  .intro,
  .architecture,
  .quality,
  .boundary,
  .clients,
  .contact {
    padding: 72px 22px;
  }

  h2 {
    font-size: 30px;
    line-height: 1.24;
  }

  .metrics,
  .quality-grid,
  .client-list {
    grid-template-columns: 1fr;
  }

  .metrics article {
    min-height: 0;
  }

  .process-step,
  .boundary-list p,
  .contact-lines p {
    grid-template-columns: 1fr;
    gap: 8px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition: none !important;
  }
}