:root {
  --ink: #0e1218;
  --ink-soft: #1a222d;
  --mist: #c5ced8;
  --paper: #e8eef4;
  --paper-dim: #d5dee8;
  --brass: #b8956c;
  --brass-bright: #d4b896;
  --line: rgba(14, 18, 24, 0.12);
  --line-light: rgba(232, 238, 244, 0.18);
  --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: "Noto Sans SC", "PingFang SC", "Hiragino Sans GB", sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

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

/* —— Nav —— */
.nav {
  position: fixed;
  inset: 0 0 auto;
  z-index: 40;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem clamp(1.25rem, 4vw, 3.5rem);
  transition: background 0.4s var(--ease), backdrop-filter 0.4s var(--ease);
}

.nav.is-solid {
  background: rgba(14, 18, 24, 0.72);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.nav-brand {
  font-family: Syne, "Noto Sans SC", sans-serif;
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: 0.22em;
  color: var(--paper);
}

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

.nav-link {
  font-size: 0.85rem;
  letter-spacing: 0.06em;
  color: rgba(232, 238, 244, 0.78);
  padding: 0.45rem 0.85rem;
  transition: color 0.25s;
}

.nav-link:hover {
  color: var(--paper);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-family: inherit;
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  border: none;
  cursor: pointer;
  transition: transform 0.35s var(--ease), background 0.3s, color 0.3s, border-color 0.3s;
}

.btn:active {
  transform: scale(0.98);
}

.btn-brass {
  background: var(--brass);
  color: var(--ink);
  padding: 0.85rem 1.6rem;
}

.btn-brass:hover {
  background: var(--brass-bright);
}

.btn-ghost {
  background: transparent;
  color: var(--paper);
  border: 1px solid var(--line-light);
  padding: 0.8rem 1.5rem;
}

.btn-ghost:hover {
  border-color: rgba(232, 238, 244, 0.45);
  background: rgba(232, 238, 244, 0.06);
}

.btn-ink {
  background: var(--ink);
  color: var(--paper);
  padding: 0.95rem 1.85rem;
}

.btn-ink:hover {
  background: var(--ink-soft);
}

.btn-outline-ink {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--ink);
  padding: 0.9rem 1.7rem;
}

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

.btn-nav {
  background: var(--brass);
  color: var(--ink);
  padding: 0.5rem 1.1rem;
  font-size: 0.82rem;
}

.btn-nav:hover {
  background: var(--brass-bright);
}

/* —— Hero —— */
.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  color: var(--paper);
  overflow: hidden;
}

.hero-visual {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-visual img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center 40%;
  transform: scale(1.06);
  animation: heroDrift 28s ease-in-out infinite alternate;
  will-change: transform;
}

.hero-veil {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg, rgba(14, 18, 24, 0.35) 0%, rgba(14, 18, 24, 0.2) 38%, rgba(14, 18, 24, 0.88) 100%),
    linear-gradient(90deg, rgba(14, 18, 24, 0.55) 0%, transparent 55%);
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  padding: 0 clamp(1.25rem, 4vw, 3.5rem) clamp(3.5rem, 8vh, 5.5rem);
  max-width: 52rem;
}

.hero-brand {
  font-family: Syne, "Noto Sans SC", sans-serif;
  font-weight: 800;
  font-size: clamp(3.4rem, 11vw, 7.2rem);
  line-height: 0.92;
  letter-spacing: 0.08em;
  margin-bottom: 1.35rem;
  opacity: 0;
  transform: translateY(28px);
  animation: riseIn 1.1s var(--ease) 0.15s forwards;
}

.hero-title {
  font-family: "Noto Serif SC", "Songti SC", serif;
  font-weight: 600;
  font-size: clamp(1.55rem, 3.6vw, 2.35rem);
  line-height: 1.35;
  letter-spacing: 0.06em;
  margin-bottom: 0.85rem;
  opacity: 0;
  transform: translateY(24px);
  animation: riseIn 1s var(--ease) 0.35s forwards;
}

.hero-lead {
  font-size: clamp(0.95rem, 1.6vw, 1.1rem);
  color: var(--mist);
  max-width: 28rem;
  margin-bottom: 2rem;
  letter-spacing: 0.04em;
  opacity: 0;
  transform: translateY(20px);
  animation: riseIn 1s var(--ease) 0.5s forwards;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  opacity: 0;
  transform: translateY(16px);
  animation: riseIn 1s var(--ease) 0.65s forwards;
}

.hero-scroll {
  position: absolute;
  right: clamp(1.25rem, 4vw, 3.5rem);
  bottom: clamp(3.5rem, 8vh, 5.5rem);
  z-index: 2;
  writing-mode: vertical-rl;
  font-size: 0.72rem;
  letter-spacing: 0.28em;
  color: rgba(232, 238, 244, 0.45);
  opacity: 0;
  animation: fadeIn 1.2s ease 1.2s forwards;
}

.hero-scroll::after {
  content: "";
  display: block;
  width: 1px;
  height: 3.2rem;
  margin: 0.75rem auto 0;
  background: linear-gradient(180deg, var(--brass), transparent);
  animation: scrollPulse 2.4s ease-in-out infinite;
}

@keyframes heroDrift {
  from { transform: scale(1.06) translate3d(0, 0, 0); }
  to { transform: scale(1.12) translate3d(-1.5%, -1%, 0); }
}

@keyframes riseIn {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  to { opacity: 1; }
}

@keyframes scrollPulse {
  0%, 100% { opacity: 0.35; transform: scaleY(1); }
  50% { opacity: 1; transform: scaleY(1.08); }
}

/* —— Sections —— */
.section {
  padding: clamp(4.5rem, 12vh, 7.5rem) clamp(1.25rem, 4vw, 3.5rem);
}

.section-inner {
  max-width: 68rem;
  margin: 0 auto;
}

.section-label {
  font-family: Syne, sans-serif;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--brass);
  margin-bottom: 1rem;
}

.section-title {
  font-family: "Noto Serif SC", "Songti SC", serif;
  font-weight: 600;
  font-size: clamp(1.7rem, 3.5vw, 2.55rem);
  line-height: 1.3;
  letter-spacing: 0.04em;
  margin-bottom: 0.85rem;
}

.section-desc {
  font-size: 1.02rem;
  color: rgba(14, 18, 24, 0.62);
  max-width: 34rem;
  letter-spacing: 0.02em;
}

.reveal {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.9s var(--ease), transform 0.9s var(--ease);
}

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

/* —— Capability —— */
.capability {
  background: var(--paper);
}

.cap-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0;
  margin-top: 3.25rem;
  border-top: 1px solid var(--line);
}

.cap-item {
  display: grid;
  grid-template-columns: 4.5rem 1fr;
  gap: 1.25rem;
  padding: 1.85rem 0;
  border-bottom: 1px solid var(--line);
}

.cap-num {
  font-family: Syne, sans-serif;
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--brass);
  padding-top: 0.3rem;
}

.cap-item h3 {
  font-family: "Noto Serif SC", serif;
  font-size: 1.2rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  margin-bottom: 0.45rem;
}

.cap-item p {
  font-size: 0.95rem;
  color: rgba(14, 18, 24, 0.58);
  max-width: 36rem;
}

@media (min-width: 860px) {
  .cap-grid {
    grid-template-columns: repeat(2, 1fr);
    column-gap: 3rem;
  }

  .cap-item:nth-child(odd) {
    border-right: 1px solid var(--line);
    padding-right: 2rem;
  }

  .cap-item:nth-child(even) {
    padding-left: 1rem;
  }
}

/* —— Flow —— */
.flow {
  background: var(--ink);
  color: var(--paper);
}

.flow .section-desc {
  color: rgba(232, 238, 244, 0.55);
}

.flow-track {
  display: grid;
  gap: 0;
  margin-top: 3rem;
  position: relative;
}

.flow-step {
  display: grid;
  grid-template-columns: 3rem 1fr;
  gap: 1.25rem;
  padding: 1.5rem 0;
  position: relative;
}

.flow-step:not(:last-child)::before {
  content: "";
  position: absolute;
  left: 0.7rem;
  top: 3.1rem;
  bottom: 0;
  width: 1px;
  background: linear-gradient(180deg, var(--brass), rgba(184, 149, 108, 0.15));
}

.flow-dot {
  width: 1.45rem;
  height: 1.45rem;
  border: 1px solid var(--brass);
  border-radius: 50%;
  margin-top: 0.2rem;
  background: var(--ink);
  position: relative;
  z-index: 1;
}

.flow-dot::after {
  content: "";
  position: absolute;
  inset: 4px;
  background: var(--brass);
  border-radius: 50%;
  opacity: 0.85;
}

.flow-step h3 {
  font-family: "Noto Serif SC", serif;
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 0.35rem;
  letter-spacing: 0.04em;
}

.flow-step p {
  font-size: 0.95rem;
  color: rgba(232, 238, 244, 0.52);
  max-width: 28rem;
}

@media (min-width: 900px) {
  .flow-track {
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
  }

  .flow-step {
    grid-template-columns: 1fr;
    padding: 0;
  }

  .flow-step:not(:last-child)::before {
    left: 0.7rem;
    right: -2rem;
    top: 0.7rem;
    bottom: auto;
    width: auto;
    height: 1px;
    background: linear-gradient(90deg, var(--brass), rgba(184, 149, 108, 0.12));
  }
}

/* —— Exchanges —— */
.exchanges {
  background: var(--paper-dim);
}

.ex-row {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 1.5rem 3rem;
  margin-top: 2.75rem;
  padding-top: 2rem;
  border-top: 1px solid var(--line);
}

.ex-name {
  font-family: Syne, sans-serif;
  font-weight: 700;
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  letter-spacing: 0.06em;
}

.ex-note {
  font-size: 0.95rem;
  color: rgba(14, 18, 24, 0.55);
  max-width: 22rem;
}

/* —— Closing CTA —— */
.closing {
  background:
    radial-gradient(ellipse 80% 60% at 70% 20%, rgba(184, 149, 108, 0.18), transparent 55%),
    var(--ink);
  color: var(--paper);
  text-align: center;
}

.closing .section-title {
  margin-left: auto;
  margin-right: auto;
}

.closing .section-desc {
  margin: 0 auto 2.25rem;
  color: rgba(232, 238, 244, 0.55);
}

.closing-cta {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.85rem;
}

/* —— Footer —— */
.site-footer {
  background: var(--ink);
  color: rgba(232, 238, 244, 0.4);
  padding: 1.5rem clamp(1.25rem, 4vw, 3.5rem) 2.25rem;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.75rem;
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  border-top: 1px solid rgba(232, 238, 244, 0.08);
}

.site-footer strong {
  font-family: Syne, sans-serif;
  font-weight: 600;
  color: rgba(232, 238, 244, 0.7);
  letter-spacing: 0.18em;
}

@media (max-width: 640px) {
  .nav-link {
    display: none;
  }

  .hero-scroll {
    display: none;
  }

  .cap-item {
    grid-template-columns: 3rem 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  .hero-visual img,
  .hero-brand,
  .hero-title,
  .hero-lead,
  .hero-cta,
  .hero-scroll,
  .hero-scroll::after,
  .reveal {
    animation: none !important;
    transition: none !important;
    opacity: 1 !important;
    transform: none !important;
  }
}