/* Trace-site — institutional solution brief */

:root {
  --ink: #101820;
  --ink-soft: #2a3544;
  --muted: #5a6878;
  --paper: #eef1f4;
  --paper-2: #e4e9ee;
  --warm: #f4f1ec;
  --line: rgba(16, 24, 32, 0.11);
  --line-strong: rgba(16, 24, 32, 0.2);
  --steel: #355066;
  --brass: #8a7349;
  --hero-fg: #f3f5f7;
  --hero-muted: rgba(243, 245, 247, 0.76);
  --header-h: 4.5rem;
  --gutter: clamp(1.25rem, 4vw, 3.75rem);
  --shell: 72rem;
  --ease: cubic-bezier(0.2, 0.8, 0.2, 1);
  --font-sans: "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei UI", "Microsoft YaHei", sans-serif;
  --font-serif: "Songti SC", "STSong", "SimSun", "Noto Serif CJK SC", serif;
  --grain: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.55'/%3E%3C/svg%3E");
}

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

html {
  scroll-behavior: auto;
}

html.is-ready-scroll {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(ellipse 70% 40% at 0% 20%, rgba(53, 80, 102, 0.07), transparent 55%),
    radial-gradient(ellipse 50% 35% at 100% 60%, rgba(138, 115, 73, 0.05), transparent 50%),
    var(--paper);
  font-family: var(--font-sans);
  font-size: 1.0625rem;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img {
  max-width: 100%;
  display: block;
}

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

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

p,
h1,
h2,
h3,
blockquote,
dl,
ul {
  margin: 0;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -3rem;
  z-index: 100;
  padding: 0.6rem 1rem;
  background: var(--ink);
  color: var(--paper);
}

.skip-link:focus {
  top: 1rem;
}

.shell {
  width: min(100% - (var(--gutter) * 2), var(--shell));
  margin-inline: auto;
}

/* 贴边宽栏：列表 / 表格 / 网格顶到左右 */
.shell-bleed {
  width: 100%;
  padding-inline: var(--gutter);
  box-sizing: border-box;
}

.shell-bleed + .shell-bleed,
.shell + .shell-bleed,
.shell-bleed + .shell {
  margin-top: 0;
}

/* Header */

.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 50;
  height: var(--header-h);
  transition: background 0.4s var(--ease), border-color 0.4s var(--ease), backdrop-filter 0.4s var(--ease);
  border-bottom: 1px solid transparent;
}

.site-header.is-scrolled {
  background: rgba(244, 241, 236, 0.92);
  backdrop-filter: blur(14px);
  border-bottom-color: var(--line);
}

.site-header.is-scrolled .brand-zh,
.site-header.is-scrolled .nav a,
.site-header.is-scrolled .nav-toggle {
  color: var(--ink);
}

.site-header.is-scrolled .brand-en {
  color: var(--muted);
}

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

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.brand-mark {
  position: relative;
  width: 2rem;
  height: 2rem;
  flex-shrink: 0;
}

.brand-mark-img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}

.brand-mark-on-light {
  opacity: 0;
}

.site-header.is-scrolled .brand-mark-on-dark,
.site-header.is-open .brand-mark-on-dark,
.site-header.is-solid .brand-mark-on-dark {
  opacity: 0;
}

.site-header.is-scrolled .brand-mark-on-light,
.site-header.is-open .brand-mark-on-light,
.site-header.is-solid .brand-mark-on-light {
  opacity: 1;
}

.brand-copy {
  display: flex;
  align-items: baseline;
  gap: 0.8rem;
}

.brand-zh {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 1.1rem;
  letter-spacing: 0.12em;
  color: var(--hero-fg);
  transition: color 0.35s var(--ease);
}

.brand-en {
  font-size: 0.68rem;
  font-weight: 500;
  letter-spacing: 0.28em;
  color: var(--hero-muted);
  transition: color 0.35s var(--ease);
}

.nav {
  display: flex;
  align-items: center;
  gap: 1.85rem;
}

.nav a {
  font-size: 0.95rem;
  font-weight: 550;
  letter-spacing: 0.07em;
  color: rgba(243, 245, 247, 0.86);
  transition: color 0.2s ease;
}

.nav a:hover {
  color: var(--hero-fg);
}

.site-header.is-scrolled .nav a:hover {
  color: var(--ink);
}

.nav-cta {
  padding: 0.35rem 0.15rem 0.28rem;
  border-bottom: 1.5px solid currentColor;
  color: var(--hero-fg);
  font-weight: 600;
}

.site-header.is-scrolled .nav-cta {
  color: var(--ink);
}

.nav-toggle {
  display: none;
  width: 2.9rem;
  height: 2.9rem;
  place-items: center;
  gap: 7px;
  flex-direction: column;
  color: var(--hero-fg);
}

.nav-toggle span {
  display: block;
  width: 1.45rem;
  height: 2px;
  background: currentColor;
  transition: transform 0.3s var(--ease);
}

.nav-toggle[aria-expanded="true"] span:first-child {
  transform: translateY(4.5px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:last-child {
  transform: translateY(-4.5px) rotate(-45deg);
}

.mobile-nav {
  display: none;
  flex-direction: column;
  padding-top: 0.35rem;
  padding-bottom: 1.25rem;
  background: rgba(242, 244, 246, 0.97);
  border-bottom: 1px solid var(--line);
}

.mobile-nav a {
  padding: 1rem 0.15rem;
  border-bottom: 1px solid var(--line);
  font-size: 1rem;
  font-weight: 550;
  color: var(--ink);
}

.mobile-nav:not([hidden]) {
  display: flex;
}

/* Hero */

.hero {
  position: relative;
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  color: var(--hero-fg);
  overflow: hidden;
}

.hero-media {
  position: absolute;
  inset: 0;
}

.hero-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: 58% center;
  transform: scale(1.035);
  transition: transform 10s var(--ease);
}

.hero.is-ready .hero-media img {
  transform: scale(1);
}

.hero-shade {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(105deg, rgba(7, 12, 18, 0.8) 0%, rgba(7, 12, 18, 0.5) 36%, rgba(7, 12, 18, 0.18) 68%, rgba(7, 12, 18, 0.3) 100%),
    linear-gradient(180deg, rgba(7, 12, 18, 0.42) 0%, rgba(7, 12, 18, 0.08) 30%, rgba(7, 12, 18, 0.68) 100%);
}

.hero-content {
  position: relative;
  z-index: 1;
  width: min(100% - (var(--gutter) * 2), 38rem);
  margin: 0 auto 0 var(--gutter);
  padding: calc(var(--header-h) + 4.75rem) 0 2.5rem;
}

.hero-brand {
  margin-bottom: 1.15rem;
  font-family: var(--font-serif);
  font-size: clamp(2.5rem, 5.2vw, 3.85rem);
  font-weight: 700;
  letter-spacing: 0.16em;
  line-height: 1.1;
}

.hero-title {
  margin-bottom: 1.25rem;
  font-family: var(--font-serif);
  font-size: clamp(1.5rem, 2.5vw, 2rem);
  font-weight: 600;
  letter-spacing: 0.08em;
  line-height: 1.35;
}

.hero-lead {
  margin-bottom: 2rem;
  max-width: 32rem;
  font-size: 1.05rem;
  line-height: 1.85;
  color: var(--hero-muted);
}

.hero-points {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem 1.15rem;
  margin: 0 0 2rem;
  font-size: 0.84rem;
  letter-spacing: 0.08em;
  color: rgba(243, 245, 247, 0.78);
}

.hero-points span {
  position: relative;
  padding-left: 0.85rem;
}

.hero-points span::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 0.35rem;
  height: 1px;
  background: rgba(243, 245, 247, 0.55);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem 1rem;
}

.hero-meta {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.75rem 1.75rem;
  width: 100%;
  margin: 0;
  padding: 1.2rem var(--gutter) 1.85rem;
  border-top: 1px solid rgba(243, 245, 247, 0.18);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(243, 245, 247, 0.66);
  box-sizing: border-box;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 2.9rem;
  padding: 0.7rem 1.4rem;
  font-size: 0.88rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  border: 1px solid transparent;
  transition: background 0.25s ease, color 0.25s ease, border-color 0.25s ease;
}

.btn-primary {
  background: var(--hero-fg);
  color: var(--ink);
}

.btn-primary:hover {
  background: #fff;
}

.btn-ghost {
  border-color: rgba(243, 245, 247, 0.4);
  color: var(--hero-fg);
}

.btn-ghost:hover {
  border-color: var(--hero-fg);
  background: rgba(243, 245, 247, 0.06);
}

/* Bridge under hero */

.bridge {
  position: relative;
  background: linear-gradient(105deg, #15202b 0%, #1c2d3a 55%, #243847 100%);
  color: var(--hero-fg);
  padding: clamp(2.25rem, 5vw, 3.25rem) 0;
  overflow: hidden;
}

.bridge::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image: var(--grain);
  opacity: 0.07;
  pointer-events: none;
  mix-blend-mode: overlay;
}

.bridge-inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(6rem, 10rem) minmax(0, 1fr);
  gap: 1rem 2.5rem;
  align-items: baseline;
}

.bridge-kicker {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: rgba(243, 245, 247, 0.45);
}

.bridge-text {
  max-width: 42rem;
  font-family: var(--font-serif);
  font-size: clamp(1.05rem, 1.8vw, 1.3rem);
  font-weight: 600;
  letter-spacing: 0.04em;
  line-height: 1.65;
  color: rgba(243, 245, 247, 0.9);
}

/* Section tones */

.section {
  position: relative;
  padding: clamp(5rem, 11vw, 8rem) 0;
}

.section + .section {
  border-top: 0;
}

.tone-warm {
  background:
    linear-gradient(180deg, #f7f4ef 0%, #f1eee8 100%);
}

.tone-cool {
  background: linear-gradient(180deg, #e7edf2 0%, #dfe6ec 100%);
}

.tone-paper {
  background: #f3f5f7;
}

.tone-cool,
.tone-ink,
.tone-paper,
.tone-night {
  content-visibility: auto;
  contain-intrinsic-size: 1200px;
}

.tone-ink {
  color: var(--hero-fg);
  background:
    linear-gradient(180deg, rgba(12, 18, 26, 0.9) 0%, rgba(12, 18, 26, 0.94) 100%),
    url("./assets/scene-bg.webp") center 40% / cover no-repeat;
  background-color: #101820;
}

.tone-ink .eyebrow {
  color: rgba(243, 245, 247, 0.5);
}

.tone-ink .section-title {
  color: var(--hero-fg);
}

.tone-ink .section-deck,
.tone-ink .scene p {
  color: rgba(243, 245, 247, 0.68);
}

.tone-ink .scene {
  background: rgba(255, 255, 255, 0.05);
  border-color: rgba(243, 245, 247, 0.12);
}

.tone-ink .scene:hover {
  background: rgba(255, 255, 255, 0.09);
  border-color: rgba(243, 245, 247, 0.26);
}

.tone-ink .scene h3 {
  color: var(--hero-fg);
}

.tone-night {
  background: #121a24;
  color: var(--hero-fg);
}

.tone-night .eyebrow {
  color: rgba(243, 245, 247, 0.48);
}

.tone-night .section-title {
  color: var(--hero-fg);
}

.tone-night .section-body {
  color: rgba(243, 245, 247, 0.68);
}

.tone-night .contact-panel {
  border-top-color: rgba(243, 245, 247, 0.16);
}

.tone-night .contact-panel dt {
  color: rgba(243, 245, 247, 0.45);
}

.tone-night .contact-panel dd {
  color: rgba(243, 245, 247, 0.82);
}

.tone-night .contact-panel a {
  color: var(--hero-fg);
}

.tone-night .contact-panel a:hover {
  color: #fff;
}

/* Outcomes — solution tiles */

.outcome-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
  margin-top: clamp(2.5rem, 5vw, 3.5rem);
  border-top: 0;
}

.outcome {
  display: grid;
  grid-template-columns: 2.5rem minmax(0, 1fr);
  gap: 0.75rem 1rem;
  padding: 1.45rem 1.35rem 1.55rem;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid rgba(16, 24, 32, 0.08);
  border-radius: 2px;
  transition: border-color 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.outcome:hover {
  background: #fff;
  border-color: rgba(53, 80, 102, 0.28);
  box-shadow: 0 10px 28px rgba(16, 30, 45, 0.06);
}

.outcome-no {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  color: var(--steel);
  padding-top: 0.3rem;
}

.outcome h3 {
  margin-bottom: 0.55rem;
  font-family: var(--font-serif);
  font-size: 1.12rem;
  font-weight: 600;
  letter-spacing: 0.03em;
}

.outcome p {
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

.bound-bar {
  display: grid;
  grid-template-columns: 7rem minmax(0, 1fr);
  gap: 1.25rem 2rem;
  align-items: start;
  margin-top: clamp(2rem, 4vw, 2.75rem);
  padding: 1.35rem 1.5rem;
  border: 1px solid rgba(16, 24, 32, 0.1);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.55);
}

.arch-figure {
  margin: clamp(2rem, 4vw, 2.75rem) 0 0;
  padding: 1rem;
  border: 1px solid rgba(16, 24, 32, 0.08);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.72);
}

.arch-diagram {
  display: block;
  width: 100%;
  height: auto;
}

.arch-caption {
  margin: 0.85rem 0.25rem 0.15rem;
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.7;
}

.footer-brand p + p {
  margin-top: 0.35rem;
}

.bound-label {
  font-size: 0.74rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--steel);
  padding-top: 0.2rem;
}

.bound-text {
  max-width: 48rem;
  color: var(--muted);
  font-size: 0.98rem;
  line-height: 1.8;
}

/* Shared section typography */

.eyebrow {
  margin-bottom: 1.1rem;
  font-size: 0.74rem;
  font-weight: 500;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--steel);
}

.section-title {
  font-family: var(--font-serif);
  font-size: clamp(1.7rem, 3vw, 2.35rem);
  font-weight: 600;
  letter-spacing: 0.05em;
  line-height: 1.3;
}

.section-deck,
.section-body,
.lede {
  margin-top: 1.35rem;
  color: var(--muted);
  font-size: 1.05rem;
  line-height: 1.85;
}

.lede {
  color: var(--ink-soft);
  font-size: 1.12rem;
}

.section-head {
  max-width: 40rem;
  margin-bottom: clamp(2.75rem, 5vw, 4rem);
}

.section-head.wide {
  max-width: 48rem;
}

/* Overview */

.split {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: 3rem 4rem;
  margin-bottom: clamp(2rem, 4vw, 3rem);
}

.split-lead .section-title {
  max-width: 10em;
}

/* Architecture layers */

.layers {
  list-style: none;
  padding: 0;
  display: grid;
  gap: 1rem;
  border-top: 0;
  position: relative;
}

.layers::before {
  display: none;
}

.layer {
  display: grid;
  grid-template-columns: minmax(11rem, 16rem) minmax(0, 1fr);
  gap: 1.75rem clamp(2rem, 4vw, 5rem);
  padding: 1.6rem 1.45rem 1.7rem;
  border: 1px solid rgba(16, 24, 32, 0.08);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.72);
  position: relative;
  transition: border-color 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.layer:hover {
  background: #fff;
  border-color: rgba(53, 80, 102, 0.28);
  box-shadow: 0 10px 28px rgba(16, 30, 45, 0.06);
}

.layer-side {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
  padding-top: 0.15rem;
  padding-left: 1.65rem;
  position: relative;
}

.layer-side::before {
  content: "";
  position: absolute;
  left: 0.85rem;
  top: 0.55rem;
  width: 0.5rem;
  height: 0.5rem;
  border: 1px solid var(--steel);
  background: var(--paper-2);
  border-radius: 50%;
}

.tone-cool .layer-side::before {
  background: #e7edf2;
}

.layer-index {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.18em;
  color: var(--muted);
}

.layer-role {
  font-family: var(--font-serif);
  font-size: 1.2rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  margin-top: 0.35rem;
}

.layer-main > p {
  color: var(--ink-soft);
  line-height: 1.8;
  max-width: 58rem;
}

.layer-points {
  list-style: none;
  padding: 1.1rem 0 0;
  display: grid;
  gap: 0.45rem;
}

.layer-points li {
  position: relative;
  padding-left: 1rem;
  color: var(--muted);
  font-size: 0.97rem;
}

.layer-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.7em;
  width: 0.35rem;
  height: 1px;
  background: var(--steel);
}

.layer-boundary {
  margin-top: 0.85rem !important;
  padding-top: 0.85rem;
  border-top: 1px dashed var(--line-strong);
  font-size: 0.92rem;
  color: var(--muted);
}

.authority {
  margin-top: clamp(3rem, 6vw, 4.5rem);
  padding: clamp(1.75rem, 3vw, 2.25rem);
  border: 1px solid rgba(16, 24, 32, 0.1);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.72);
}

.authority-head {
  display: grid;
  grid-template-columns: minmax(8rem, 12rem) minmax(0, 1fr);
  gap: 1.5rem;
  margin-bottom: 1.75rem;
  align-items: baseline;
}

.authority-head h3 {
  font-family: var(--font-serif);
  font-size: 1.2rem;
  font-weight: 600;
  letter-spacing: 0.04em;
}

.authority-head p {
  color: var(--muted);
  font-size: 0.98rem;
}

.authority-table {
  border-top: 1px solid var(--line-strong);
}

.authority-row {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr 1.2fr;
  gap: 1rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--line);
  font-size: 0.95rem;
}

.authority-row.head {
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}

.authority-row:not(.head) span:first-child {
  color: var(--ink-soft);
  font-weight: 500;
}

.authority-row:not(.head) span:nth-child(2) {
  font-family: var(--font-sans);
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--steel);
}

.authority-row:not(.head) span:nth-child(3) {
  color: var(--muted);
}

/* Capabilities */

.capabilities {
  background: var(--paper-2);
}

.spec-list {
  border-top: 1px solid var(--line-strong);
}

.spec {
  display: grid;
  grid-template-columns: 3.5rem minmax(0, 1fr);
  gap: 1.25rem 1.75rem;
  padding: 1.65rem 0;
  border-bottom: 1px solid var(--line);
}

.spec-no {
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  color: var(--muted);
  padding-top: 0.35rem;
}

.spec h3 {
  margin-bottom: 0.45rem;
  font-family: var(--font-serif);
  font-size: 1.18rem;
  font-weight: 600;
  letter-spacing: 0.04em;
}

.spec p {
  max-width: 58rem;
  color: var(--muted);
  font-size: 0.98rem;
  line-height: 1.8;
}

/* Scenarios — industry tiles */

.scene-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
  border-top: 0;
}

.scene {
  padding: 1.5rem 1.35rem 1.6rem;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(243, 245, 247, 0.12);
  border-radius: 2px;
  transition: background 0.2s ease, border-color 0.2s ease;
}

.scene:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(243, 245, 247, 0.28);
}

.scene h3 {
  margin-bottom: 0.55rem;
  font-family: var(--font-serif);
  font-size: 1.12rem;
  font-weight: 600;
  letter-spacing: 0.03em;
}

.scene p {
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* Deployment */

.deploy-modes {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
  margin-bottom: clamp(2rem, 4vw, 2.75rem);
  border-top: 0;
}

.mode {
  padding: 1.5rem 1.35rem 1.6rem;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid rgba(16, 24, 32, 0.08);
  border-radius: 2px;
  transition: border-color 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.mode:hover {
  background: #fff;
  border-color: rgba(53, 80, 102, 0.28);
  box-shadow: 0 10px 28px rgba(16, 30, 45, 0.06);
}

.mode-label {
  display: block;
  margin-bottom: 0.7rem;
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--steel);
}

.mode h3 {
  margin-bottom: 0.55rem;
  font-family: var(--font-serif);
  font-size: 1.12rem;
  font-weight: 600;
  letter-spacing: 0.03em;
}

.mode p {
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

.deploy-note {
  display: grid;
  grid-template-columns: 1.35fr 0.65fr;
  gap: 2.5rem;
  padding: 1.5rem 1.5rem;
  border: 1px solid rgba(16, 24, 32, 0.1);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.72);
}

.deploy-note h3 {
  margin-bottom: 0.75rem;
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: 0.04em;
}

.deploy-note p {
  color: var(--muted);
  line-height: 1.8;
}

.deploy-note ul {
  list-style: none;
  padding: 0;
  display: grid;
  gap: 0.7rem;
  align-content: start;
}

.deploy-note li {
  padding-bottom: 0.7rem;
  border-bottom: 1px solid var(--line);
  font-size: 0.95rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--ink-soft);
}

/* Custom */

.custom-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
  border-top: 0;
}

.custom-item {
  display: grid;
  grid-template-columns: 2.5rem minmax(0, 1fr);
  gap: 0.75rem 1rem;
  padding: 1.45rem 1.35rem 1.55rem;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid rgba(16, 24, 32, 0.08);
  border-radius: 2px;
  transition: border-color 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.custom-item:hover {
  background: #fff;
  border-color: rgba(53, 80, 102, 0.28);
  box-shadow: 0 10px 28px rgba(16, 30, 45, 0.06);
}

.custom-no {
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  color: var(--steel);
  padding-top: 0.3rem;
}

.custom-item h3 {
  margin-bottom: 0.55rem;
  font-family: var(--font-serif);
  font-size: 1.12rem;
  font-weight: 600;
  letter-spacing: 0.03em;
}

.custom-item p {
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

/* Contact */

.contact-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 3rem 4rem;
  align-items: start;
}

.contact-panel {
  padding: 1.5rem 1.5rem;
  border: 1px solid rgba(243, 245, 247, 0.14);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.04);
}

.contact-panel dl {
  display: grid;
  gap: 1.4rem;
}

.contact-panel dt {
  margin-bottom: 0.35rem;
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.contact-panel dd {
  color: var(--ink-soft);
  line-height: 1.7;
}

.contact .contact-panel {
  margin-top: 1.75rem;
}

.data-deploy-note {
  margin-top: 1.35rem;
  padding: 1.15rem 0 0;
  border-top: 1px solid rgba(243, 245, 247, 0.14);
  scroll-margin-top: calc(var(--header-h) + 1.25rem);
  border-radius: 2px;
  transition: background 0.45s var(--ease), box-shadow 0.45s var(--ease);
}

.data-deploy-note.is-flash {
  background: rgba(243, 245, 247, 0.06);
  box-shadow: inset 0 0 0 1px rgba(243, 245, 247, 0.12);
}

#product,
#architecture,
#stack,
#scenarios,
#deploy,
#custom,
#join,
#contact,
#data-deploy,
#top {
  scroll-margin-top: calc(var(--header-h) + 0.75rem);
}

/* Join */

.join {
  background:
    linear-gradient(180deg, rgba(244, 241, 236, 0.55), transparent 42%),
    var(--paper);
}

.join-inner {
  display: grid;
  gap: 1.75rem;
}

.join-panel {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(14rem, 0.7fr);
  gap: 1.75rem 2.5rem;
  align-items: end;
  padding: 1.65rem 1.55rem 1.75rem;
  border: 1px solid rgba(16, 24, 32, 0.1);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.78);
}

.join-copy p {
  color: var(--muted);
  line-height: 1.8;
}

.join-points {
  list-style: none;
  padding: 0;
  margin: 1.1rem 0 0;
  display: grid;
  gap: 0.55rem;
}

.join-points li {
  padding-left: 0.95rem;
  position: relative;
  font-size: 0.95rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--ink-soft);
}

.join-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 0.35rem;
  height: 0.35rem;
  border-radius: 1px;
  background: var(--steel);
}

.join-actions {
  display: grid;
  gap: 0.75rem;
  justify-items: stretch;
}

.join-actions .btn {
  justify-content: center;
  text-align: center;
}

.join-mail-line {
  display: block;
  text-align: center;
  font-size: 0.9rem;
  color: var(--steel);
  word-break: break-all;
}

.join-mail-line:hover {
  color: var(--ink);
}

.data-deploy-label {
  margin: 0 0 0.45rem;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(243, 245, 247, 0.48);
}

.data-deploy-note p:last-child {
  margin: 0;
  color: rgba(243, 245, 247, 0.62);
  font-size: 0.92rem;
  line-height: 1.75;
}

.lead-form {
  display: grid;
  gap: 0.9rem;
  padding: 1.5rem 1.45rem 1.55rem;
  border: 1px solid rgba(243, 245, 247, 0.14);
  border-radius: 2px;
  background: rgba(255, 255, 255, 0.05);
}

.lead-form-title {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  color: var(--hero-fg);
}

.lead-form-deck {
  margin: -0.25rem 0 0.2rem;
  color: rgba(243, 245, 247, 0.62);
  font-size: 0.92rem;
  line-height: 1.65;
}

.lead-form label {
  display: grid;
  gap: 0.35rem;
}

.lead-form label span {
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: rgba(243, 245, 247, 0.55);
}

.lead-form label em {
  font-style: normal;
  color: rgba(214, 168, 112, 0.9);
}

.lead-form input,
.lead-form textarea {
  width: 100%;
  border: 1px solid rgba(243, 245, 247, 0.16);
  border-radius: 2px;
  background: rgba(8, 12, 18, 0.35);
  color: var(--hero-fg);
  padding: 0.7rem 0.8rem;
  font: inherit;
}

.lead-form input::placeholder,
.lead-form textarea::placeholder {
  color: rgba(243, 245, 247, 0.35);
}

.lead-form input:focus,
.lead-form textarea:focus {
  outline: none;
  border-color: rgba(243, 245, 247, 0.38);
}

.lead-form textarea {
  resize: vertical;
  min-height: 6rem;
}

.lead-form-msg {
  margin: 0;
  font-size: 0.9rem;
  color: #e2a3a3;
}

.lead-form-msg.is-ok {
  color: #9dceb4;
}

.lead-form .btn {
  justify-self: start;
  margin-top: 0.2rem;
}

/* Footer */

.site-footer {
  border-top: 1px solid rgba(243, 245, 247, 0.1);
  background: #0c1219;
  padding: 3rem 0 2rem;
  color: rgba(243, 245, 247, 0.7);
}

.footer-inner {
  display: grid;
  gap: 2.25rem;
}

.footer-main {
  display: grid;
  grid-template-columns: minmax(14rem, 1.15fr) minmax(0, 2fr);
  gap: 2.5rem 3.5rem;
  align-items: start;
}

.footer-brand-row {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  margin-bottom: 0.85rem;
}

.footer-brand-row .brand-zh,
.footer-brand-row .brand-en {
  display: block;
}

.footer-brand-row .brand-zh {
  color: var(--hero-fg);
  font-size: 1.05rem;
  margin-bottom: 0.15rem;
}

.footer-brand-row .brand-en {
  color: rgba(243, 245, 247, 0.45);
}

.footer-mark {
  width: 2.35rem;
  height: 2.35rem;
  object-fit: contain;
  flex-shrink: 0;
}

.footer-brand .brand-en {
  margin-left: 0;
}

.footer-brand p {
  margin-top: 0.45rem;
  font-size: 0.88rem;
  line-height: 1.65;
  color: rgba(243, 245, 247, 0.45);
}

.footer-contact-line {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem 0.65rem;
  margin-top: 1rem !important;
  font-size: 0.88rem !important;
  color: rgba(243, 245, 247, 0.55) !important;
}

.footer-contact-line a {
  color: rgba(243, 245, 247, 0.72);
  border-bottom: 1px solid rgba(243, 245, 247, 0.18);
  padding-bottom: 0.05rem;
}

.footer-contact-line a:hover {
  color: #fff;
  border-bottom-color: rgba(243, 245, 247, 0.5);
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1.75rem 2rem;
}

.footer-col {
  display: grid;
  gap: 0.55rem;
  align-content: start;
}

.footer-col h3 {
  margin: 0 0 0.35rem;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(243, 245, 247, 0.88);
}

.footer-col a {
  font-size: 0.9rem;
  color: rgba(243, 245, 247, 0.5);
  line-height: 1.5;
}

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

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 0.65rem 1.5rem;
  padding-top: 1.35rem;
  border-top: 1px solid rgba(243, 245, 247, 0.1);
}

.footer-copy {
  margin: 0;
  font-size: 0.82rem;
  color: rgba(243, 245, 247, 0.4);
}

.footer-beian {
  font-size: 0.82rem;
  color: rgba(243, 245, 247, 0.4);
}

.footer-beian:hover {
  color: rgba(243, 245, 247, 0.75);
}

/* Motion — restrained */

.reveal {
  opacity: 0;
  transform: translateY(0.7rem);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}

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

.hero .reveal:nth-child(1) { transition-delay: 0.05s; }
.hero .reveal:nth-child(2) { transition-delay: 0.12s; }
.hero .reveal:nth-child(3) { transition-delay: 0.2s; }
.hero .reveal:nth-child(4) { transition-delay: 0.28s; }
.hero .reveal:nth-child(5) { transition-delay: 0.34s; }

.hero-content .reveal:nth-child(1) { transition-delay: 0.05s; }
.hero-content .reveal:nth-child(2) { transition-delay: 0.12s; }
.hero-content .reveal:nth-child(3) { transition-delay: 0.18s; }
.hero-content .reveal:nth-child(4) { transition-delay: 0.24s; }
.hero-content .reveal:nth-child(5) { transition-delay: 0.3s; }

/* Responsive */

@media (max-width: 980px) {
  .split,
  .authority-head,
  .deploy-note,
  .contact-grid,
  .bound-bar,
  .outcome-grid,
  .custom-grid,
  .join-panel,
  .bridge-inner,
  .footer-main {
    grid-template-columns: 1fr;
  }

  .footer-main {
    gap: 2rem;
  }

  .footer-cols {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .footer-bottom {
    justify-content: flex-start;
  }

  .layers::before,
  .layer-side::before {
    display: none;
  }

  .layer-side {
    padding-left: 0;
  }

  .deploy-modes,
  .scene-grid {
    grid-template-columns: 1fr;
  }

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

  .authority-row {
    grid-template-columns: 1fr;
    gap: 0.25rem;
  }
}

@media (max-width: 720px) {
  .nav {
    display: none;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .footer-cols {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .hero-content {
    width: min(100% - (var(--gutter) * 2), 40rem);
    margin-left: var(--gutter);
    margin-right: var(--gutter);
    padding-bottom: 2rem;
  }

  .site-header.is-open {
    background: rgba(242, 244, 246, 0.97);
  }

  .site-header.is-open .brand-zh,
  .site-header.is-open .nav-toggle {
    color: var(--ink);
  }

  .site-header.is-open .brand-en {
    color: var(--muted);
  }
}

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

  .reveal,
  .hero-media img,
  .float-panel {
    transition: none !important;
  }

  .reveal,
  .hero-media img {
    transform: none !important;
    opacity: 1 !important;
  }

  .float-contact {
    transition: none !important;
  }
}

/* Floating contact — side rail */

.float-contact {
  position: fixed;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  z-index: 60;
  display: flex;
  flex-direction: row-reverse;
  align-items: center;
  gap: 0;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.35s var(--ease);
}

.float-contact.is-visible {
  opacity: 1;
  pointer-events: none;
}

.float-contact.is-visible .float-trigger,
.float-contact.is-visible .float-panel {
  pointer-events: auto;
}

.float-trigger {
  writing-mode: vertical-rl;
  text-orientation: mixed;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin: 0;
  padding: 1.35rem 0.55rem;
  border: 1px solid rgba(16, 24, 32, 0.14);
  border-right: 0;
  border-radius: 2px 0 0 2px;
  background: rgba(255, 255, 255, 0.94);
  color: var(--ink);
  font: inherit;
  font-size: 0.88rem;
  font-weight: 600;
  letter-spacing: 0.42em;
  line-height: 1;
  cursor: pointer;
  box-shadow: -4px 6px 18px rgba(16, 30, 45, 0.06);
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.float-trigger:hover {
  background: #fff;
  border-color: rgba(53, 80, 102, 0.35);
  color: var(--steel);
}

.float-trigger[aria-expanded="true"] {
  background: var(--steel);
  border-color: var(--steel);
  color: #fff;
}

.float-panel {
  width: min(34rem, calc(100vw - 3.25rem));
  margin-right: 0.55rem;
  background: #fff;
  border: 1px solid rgba(16, 24, 32, 0.1);
  border-radius: 2px;
  overflow: hidden;
  box-shadow: 0 12px 32px rgba(16, 30, 45, 0.12);
  transform-origin: center right;
  animation: float-in 0.22s var(--ease);
}

.float-panel[hidden] {
  display: none !important;
}

@keyframes float-in {
  from {
    opacity: 0;
    transform: translateX(0.4rem);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

.float-panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.8rem 1rem;
  background: #1c2834;
  color: #fff;
  font-size: 0.92rem;
  font-weight: 600;
  letter-spacing: 0.08em;
}

.float-close {
  border: 0;
  background: transparent;
  color: inherit;
  font-size: 1.35rem;
  line-height: 1;
  cursor: pointer;
  padding: 0.1rem 0.25rem;
  opacity: 0.85;
}

.float-close:hover {
  opacity: 1;
}

.float-panel-body {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
}

.float-col {
  padding: 1.1rem 1.05rem 1.2rem;
}

.float-col + .float-col {
  border-left: 1px solid var(--line);
}

.float-col-label {
  margin: 0 0 0.85rem;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}

.float-item {
  display: grid;
  grid-template-columns: 1.5rem 1fr;
  gap: 0.65rem;
  margin-bottom: 0.85rem;
  align-items: start;
}

.float-item:last-of-type {
  margin-bottom: 0.75rem;
}

.float-contact-line {
  color: var(--ink);
  font-weight: 550;
  word-break: break-all;
}

.float-contact-line:hover {
  color: var(--steel);
}

.float-note {
  margin: 0.15rem 0 0.85rem;
  padding: 0.75rem 0.8rem;
  border-left: 2px solid rgba(53, 80, 102, 0.35);
  background: rgba(53, 80, 102, 0.04);
  color: var(--muted);
  font-size: 0.84rem;
  line-height: 1.65;
}

.float-ico {
  color: var(--steel);
  margin-top: 0.1rem;
}

.float-item strong {
  display: block;
  font-size: 0.95rem;
  font-weight: 650;
  letter-spacing: 0.02em;
  color: var(--ink);
}

.float-item p {
  margin: 0.25rem 0 0;
  font-size: 0.84rem;
  line-height: 1.55;
  color: var(--muted);
}

.float-link {
  display: inline-block;
  margin-top: 0.15rem;
  font-size: 0.84rem;
  color: var(--steel);
  border-bottom: 1px solid rgba(53, 80, 102, 0.35);
  padding-bottom: 0.1rem;
}

.float-link:hover {
  border-bottom-color: var(--steel);
}

.float-form {
  display: grid;
  gap: 0.65rem;
}

.float-form label {
  display: grid;
  gap: 0.25rem;
}

.float-form label span {
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.float-form label em {
  font-style: normal;
  color: var(--brass);
}

.float-form input,
.float-form textarea {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 2px;
  padding: 0.55rem 0.65rem;
  font: inherit;
  font-size: 0.9rem;
  color: var(--ink);
  background: #fff;
}

.float-form input:focus,
.float-form textarea:focus {
  outline: none;
  border-color: rgba(53, 80, 102, 0.45);
}

.float-form textarea {
  resize: vertical;
  min-height: 4.2rem;
}

.float-form-msg {
  font-size: 0.84rem;
}

.float-submit {
  justify-self: start;
  min-height: 2.4rem;
  padding: 0.5rem 1.1rem;
  font-size: 0.84rem;
  background: var(--steel);
  color: #fff;
}

.float-submit:hover {
  background: #2c4458;
  color: #fff;
}

@media (max-width: 720px) {
  .float-contact {
    top: auto;
    bottom: 5.5rem;
    transform: none;
  }

  .float-panel {
    width: min(22.5rem, calc(100vw - 3rem));
    margin-right: 0.4rem;
  }

  .float-panel-body {
    grid-template-columns: 1fr;
  }

  .float-col + .float-col {
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .float-trigger {
    padding: 1.1rem 0.5rem;
    letter-spacing: 0.32em;
  }
}