:root {
  --ink: #101418;
  --ink-soft: #1a2128;
  --paper: #f3f1ec;
  --paper-2: #e8e4dc;
  --copper: #c46a3a;
  --copper-deep: #9a4f28;
  --teal: #2a6f6a;
  --mist: rgba(243, 241, 236, 0.72);
  --line: rgba(16, 20, 24, 0.12);
  --line-light: rgba(243, 241, 236, 0.16);
  --muted: #6b727a;
  --ok: #2f7d57;
  --max: 1120px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Sora", "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.65;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

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

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

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

.wrap {
  width: min(var(--max), calc(100% - 40px));
  margin-inline: auto;
}

/* ——— Nav ——— */
.nav {
  position: fixed;
  inset: 0 0 auto;
  z-index: 40;
  transition: background 0.35s var(--ease), backdrop-filter 0.35s var(--ease), border-color 0.35s var(--ease);
  border-bottom: 1px solid transparent;
}

.nav.is-solid {
  background: rgba(16, 20, 24, 0.88);
  backdrop-filter: blur(14px);
  border-bottom-color: var(--line-light);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 68px;
  gap: 24px;
}

.nav__brand {
  display: flex;
  align-items: baseline;
  gap: 10px;
  color: var(--paper);
  letter-spacing: 0.08em;
}

.nav__brand strong {
  font-family: "Noto Serif SC", "Songti SC", serif;
  font-weight: 600;
  font-size: 1.15rem;
}

.nav__brand span {
  font-size: 0.72rem;
  opacity: 0.55;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 22px;
  list-style: none;
}

.nav__links a {
  color: rgba(243, 241, 236, 0.78);
  font-size: 0.88rem;
  transition: color 0.2s ease;
}

.nav__links a:hover {
  color: #fff;
}

.nav__cta {
  color: var(--ink) !important;
  background: var(--paper);
  padding: 0.55rem 1rem;
  font-size: 0.82rem !important;
  letter-spacing: 0.04em;
}

.nav__toggle {
  display: none;
  width: 42px;
  height: 42px;
  place-items: center;
  color: var(--paper);
}

.nav__toggle span {
  display: block;
  width: 18px;
  height: 1.5px;
  background: currentColor;
  position: relative;
}

.nav__toggle span::before,
.nav__toggle span::after {
  content: "";
  position: absolute;
  inset-inline: 0;
  height: inherit;
  background: inherit;
}

.nav__toggle span::before { top: -6px; }
.nav__toggle span::after { top: 6px; }

/* ——— Hero ——— */
.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100dvh;
  display: grid;
  align-items: end;
  color: var(--paper);
  overflow: hidden;
  background: var(--ink);
}

.hero__media {
  position: absolute;
  inset: 0;
}

.hero__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transform: scale(1.06);
  animation: heroDrift 18s var(--ease) infinite alternate;
}

.hero__grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(243, 241, 236, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(243, 241, 236, 0.04) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse 70% 60% at 50% 40%, #000 20%, transparent 75%);
  animation: gridPulse 10s ease-in-out infinite alternate;
  pointer-events: none;
}

.hero__glow {
  position: absolute;
  width: 42vw;
  height: 42vw;
  right: -8%;
  top: 12%;
  border: 1px solid rgba(224, 160, 121, 0.16);
  border-radius: 50%;
  animation: heroDrift 16s var(--ease) infinite alternate;
  pointer-events: none;
}

.hero__glow::before {
  content: "";
  position: absolute;
  inset: 12%;
  border: 1px solid rgba(42, 111, 106, 0.22);
  border-radius: 50%;
}

.hero__shade {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(12, 16, 20, 0.55) 0%, rgba(12, 16, 20, 0.72) 48%, rgba(12, 16, 20, 0.96) 100%),
    linear-gradient(90deg, rgba(12, 16, 20, 0.5) 0%, transparent 55%);
}

@keyframes gridPulse {
  from { opacity: 0.55; }
  to { opacity: 1; }
}

.hero__content {
  position: relative;
  z-index: 1;
  padding: 0 0 72px;
  width: min(var(--max), calc(100% - 40px));
  margin-inline: auto;
}

.hero__brand {
  font-family: "Noto Serif SC", "Songti SC", serif;
  font-size: clamp(2.8rem, 8vw, 5.4rem);
  font-weight: 600;
  letter-spacing: 0.14em;
  line-height: 1.05;
  margin-bottom: 18px;
  animation: rise 0.9s var(--ease) both;
}

.hero__brand em {
  font-style: normal;
  color: var(--copper);
}

.hero__title {
  max-width: 16ch;
  font-size: clamp(1.35rem, 3.2vw, 2rem);
  font-weight: 500;
  letter-spacing: 0.04em;
  line-height: 1.35;
  margin-bottom: 14px;
  animation: rise 0.9s 0.08s var(--ease) both;
}

.hero__lead {
  max-width: 36em;
  color: rgba(243, 241, 236, 0.78);
  font-size: 1.02rem;
  margin-bottom: 28px;
  animation: rise 0.9s 0.16s var(--ease) both;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  animation: rise 0.9s 0.24s var(--ease) both;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 1.25rem;
  font-size: 0.92rem;
  letter-spacing: 0.04em;
  transition: transform 0.25s var(--ease), background 0.25s ease, color 0.25s ease, border-color 0.25s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn--solid {
  background: var(--copper);
  color: #fff;
}

.btn--solid:hover {
  background: var(--copper-deep);
}

.btn--ghost {
  border: 1px solid rgba(243, 241, 236, 0.35);
  color: var(--paper);
}

.btn--ghost:hover {
  border-color: #fff;
  background: rgba(255, 255, 255, 0.06);
}

.btn--dark {
  background: var(--ink);
  color: var(--paper);
}

.btn--line {
  border: 1px solid var(--ink);
  color: var(--ink);
}

/* ——— Sections ——— */
.section {
  padding: 96px 0;
}

.section--ink {
  background: var(--ink);
  color: var(--paper);
}

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

.section__head {
  margin-bottom: 48px;
  max-width: 40rem;
}

.eyebrow {
  display: block;
  font-size: 0.78rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--copper);
  margin-bottom: 12px;
}

.section--ink .eyebrow {
  color: #e0a079;
}

.section__head h2 {
  font-family: "Noto Serif SC", "Songti SC", serif;
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 600;
  letter-spacing: 0.06em;
  line-height: 1.25;
  margin-bottom: 14px;
}

.section__head p {
  color: var(--muted);
  font-size: 1.02rem;
}

.section--ink .section__head p {
  color: rgba(243, 241, 236, 0.68);
}

/* Dual pillars */
.pillars {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.pillar {
  position: relative;
  min-height: 420px;
  overflow: hidden;
  color: var(--paper);
  isolation: isolate;
}

.pillar img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.8s var(--ease);
}

.pillar:hover img {
  transform: scale(1.04);
}

.pillar__shade {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(16, 20, 24, 0.2), rgba(16, 20, 24, 0.88) 72%);
  z-index: 1;
}

.pillar__body {
  position: relative;
  z-index: 2;
  height: 100%;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding: 28px;
}

.pillar__body h3 {
  font-family: "Noto Serif SC", serif;
  font-size: 1.65rem;
  letter-spacing: 0.08em;
  margin: 8px 0 10px;
}

.pillar__body p {
  color: rgba(243, 241, 236, 0.78);
  font-size: 0.95rem;
  max-width: 28em;
  margin-bottom: 18px;
}

.pillar__link {
  color: #e0a079;
  font-size: 0.88rem;
  letter-spacing: 0.06em;
}

/* Engines */
.engines {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}

.engine {
  background: var(--paper);
  padding: 28px 22px 30px;
}

.engine__no {
  font-size: 0.75rem;
  letter-spacing: 0.18em;
  color: var(--copper);
  margin-bottom: 18px;
}

.engine h3 {
  font-size: 1.15rem;
  letter-spacing: 0.04em;
  margin-bottom: 10px;
}

.engine p {
  color: var(--muted);
  font-size: 0.92rem;
  margin-bottom: 18px;
  min-height: 4.4em;
}

.engine__metric {
  font-family: "Sora", sans-serif;
  font-size: 1.35rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--ink);
}

.engine__metric small {
  display: block;
  margin-top: 4px;
  font-size: 0.75rem;
  font-weight: 400;
  color: var(--muted);
  letter-spacing: 0.04em;
}

/* Metrics strip */
.metrics {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  margin-top: 36px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
}

.metric strong {
  display: block;
  font-size: clamp(1.5rem, 3vw, 2rem);
  letter-spacing: -0.02em;
  margin-bottom: 4px;
}

.metric span {
  color: var(--muted);
  font-size: 0.88rem;
}

.section--ink .metric span {
  color: rgba(243, 241, 236, 0.6);
}

/* Architecture */
.arch {
  display: grid;
  gap: 10px;
}

.arch__layer {
  padding: 22px 24px;
  border: 1px solid var(--line-light);
  background: rgba(255, 255, 255, 0.03);
  display: grid;
  grid-template-columns: 160px 1fr;
  gap: 18px;
  align-items: start;
}

.arch__layer h3 {
  font-size: 1rem;
  letter-spacing: 0.06em;
}

.arch__layer p {
  color: rgba(243, 241, 236, 0.7);
  font-size: 0.94rem;
}

.arch__layer--mid {
  border-color: rgba(196, 106, 58, 0.45);
  background: rgba(196, 106, 58, 0.08);
}

.rdk {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  margin-top: 28px;
}

.rdk__item {
  padding: 18px 16px;
  border-top: 2px solid var(--copper);
  background: rgba(255, 255, 255, 0.04);
}

.rdk__item strong {
  display: block;
  font-size: 1.05rem;
  margin-bottom: 6px;
}

.rdk__item b {
  display: block;
  color: #e0a079;
  font-size: 1.2rem;
  margin-bottom: 8px;
}

.rdk__item span {
  color: rgba(243, 241, 236, 0.62);
  font-size: 0.86rem;
}

/* Academy */
.academy-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 28px;
  align-items: stretch;
}

.academy-visual {
  overflow: hidden;
  min-height: 360px;
  background: var(--ink);
}

.academy-visual img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.tracks {
  display: grid;
  gap: 14px;
}

.track {
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}

.track:first-child {
  padding-top: 0;
}

.track h3 {
  font-size: 1.1rem;
  margin-bottom: 6px;
  letter-spacing: 0.04em;
}

.track p {
  color: var(--muted);
  font-size: 0.92rem;
}

.flow {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 10px;
  margin-top: 40px;
}

.flow__step {
  padding: 16px 14px;
  background: #fff;
  border-top: 2px solid var(--teal);
}

.flow__step b {
  display: block;
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  color: var(--teal);
  margin-bottom: 8px;
}

.flow__step span {
  font-size: 0.95rem;
}

/* Cases */
.cases {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.case {
  background: #fff;
  padding: 28px;
  border: 1px solid var(--line);
}

.case__tag {
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  color: var(--copper);
  margin-bottom: 12px;
}

.case h3 {
  font-family: "Noto Serif SC", serif;
  font-size: 1.35rem;
  letter-spacing: 0.05em;
  margin-bottom: 12px;
}

.case p {
  color: var(--muted);
  font-size: 0.95rem;
  margin-bottom: 16px;
}

.case ul {
  list-style: none;
  display: grid;
  gap: 8px;
}

.case li {
  position: relative;
  padding-left: 14px;
  font-size: 0.92rem;
}

.case li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.65em;
  width: 6px;
  height: 1px;
  background: var(--copper);
}

/* Company */
.about {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 48px;
  align-items: start;
}

.about__copy h2 {
  font-family: "Noto Serif SC", serif;
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  letter-spacing: 0.06em;
  margin: 10px 0 18px;
}

.about__copy p {
  color: var(--muted);
  margin-bottom: 14px;
}

.values {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
  margin-top: 24px;
}

.values span {
  text-align: center;
  padding: 14px 8px;
  background: #fff;
  border: 1px solid var(--line);
  letter-spacing: 0.2em;
  font-size: 0.92rem;
}

.facts {
  display: grid;
  gap: 12px;
}

.fact {
  padding: 20px 22px;
  background: #fff;
  border-left: 3px solid var(--copper);
}

.fact strong {
  display: block;
  font-size: 1.4rem;
  margin-bottom: 4px;
}

.fact span {
  color: var(--muted);
  font-size: 0.9rem;
}

/* Contact */
.contact {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 32px;
  align-items: end;
}

.contact h2 {
  font-family: "Noto Serif SC", serif;
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  letter-spacing: 0.08em;
  margin: 10px 0 12px;
}

.contact p {
  color: rgba(243, 241, 236, 0.68);
  max-width: 34em;
}

.contact__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.footer {
  padding: 28px 0 40px;
  background: #0a0d10;
  color: rgba(243, 241, 236, 0.5);
  font-size: 0.85rem;
}

.footer__inner {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

/* Reveal */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}

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

@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

@keyframes heroDrift {
  from { transform: scale(1.04) translate3d(0, 0, 0); }
  to { transform: scale(1.08) translate3d(-1.2%, -0.8%, 0); }
}

/* Responsive */
@media (max-width: 960px) {
  .pillars,
  .cases,
  .about,
  .academy-grid,
  .contact {
    grid-template-columns: 1fr;
  }

  .engines,
  .metrics,
  .rdk,
  .flow,
  .values {
    grid-template-columns: 1fr 1fr;
  }

  .arch__layer {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .nav__links {
    display: none;
  }

  .nav.is-open .nav__links {
    display: flex;
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: rgba(16, 20, 24, 0.96);
    padding: 8px 20px 20px;
  }

  .nav.is-open .nav__links a {
    padding: 14px 0;
    border-bottom: 1px solid var(--line-light);
  }

  .nav__toggle {
    display: grid;
  }

  .pillar {
    min-height: 340px;
  }
}

@media (max-width: 560px) {
  .wrap {
    width: calc(100% - 28px);
  }

  .section {
    padding: 72px 0;
  }

  .engines,
  .metrics,
  .rdk,
  .flow,
  .values {
    grid-template-columns: 1fr;
  }

  .hero__content {
    padding-bottom: 48px;
  }

  .nav__brand span {
    display: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }

  html {
    scroll-behavior: auto;
  }
}