@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;600;700;800&display=swap');

/* ============================================================
   Reset & Base
   ============================================================ */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  line-height: 1.6;
  scroll-behavior: smooth;
  background: #1f1f1f;
  color: #ffffff;
  font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  -webkit-text-size-adjust: 100%;
}

body {
  min-height: 100vh;
  background: #1f1f1f;
  color: #ffffff;
  overflow-x: hidden;
}

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

ul {
  list-style: none;
}

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

/* ============================================================
   Scroll margin for anchor sections
   ============================================================ */
article[id] {
  scroll-margin-top: 110px;
}

/* ============================================================
   Page Wrapper
   ============================================================ */
.page-wrapper {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  position: relative;
}

/* ============================================================
   Brand Bar (品牌独占一行 + CTA)
   ============================================================ */
.brand-bar {
  position: relative;
  z-index: 40;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 40px;
  background: #1f1f1f;
  border-bottom: 1px solid rgba(255,255,255,0.08);
  box-shadow: 0 2px 16px rgba(0,0,0,0.6);
}

.brand-bar__logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.brand-bar__wordmark,
.brand-bar__name {
  font-size: 1.4rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #ffffff;
  white-space: nowrap;
}

.brand-logo,
.brand-logomark {
  height: 36px;
  width: auto;
}

/* ============================================================
   CTA Button
   ============================================================ */
.btn-cta {
  display: inline-block;
  padding: 10px 24px;
  background: #ffffff;
  color: #1f1f1f;
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  border-radius: 0;
  border: none;
  cursor: pointer;
  transition: background 0.18s, color 0.18s, transform 0.15s;
  white-space: nowrap;
  min-height: 40px;
  line-height: 1.2;
}

.btn-cta:hover {
  background: #f5f5f5;
  transform: translateY(-2px);
}

.btn-cta--hero {
  margin-top: 24px;
  padding: 14px 36px;
  font-size: 1rem;
}

/* ============================================================
   Sticky Nav (Aside > Nav > Ul > Li > A)
   ============================================================ */
.site-aside {
  position: sticky;
  top: 0;
  z-index: 30;
  background: rgba(31,31,31,0.92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(255,255,255,0.06);
  box-shadow: 0 4px 24px rgba(0,0,0,0.5);
}

.sticky-nav ul {
  display: flex;
  align-items: center;
  gap: 0;
  padding: 0 40px;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
}

.sticky-nav ul::-webkit-scrollbar {
  display: none;
}

.sticky-nav ul li {
  flex-shrink: 0;
}

.nav-link {
  display: block;
  padding: 14px 18px;
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  color: rgba(255,255,255,0.65);
  border-bottom: 2px solid transparent;
  transition: color 0.18s, border-color 0.18s;
  white-space: nowrap;
  min-height: 44px;
  line-height: 1;
  display: flex;
  align-items: center;
}

.nav-link:hover,
.nav-link--active {
  color: #ffffff;
  border-bottom-color: #ffffff;
}

/* ============================================================
   Hero
   ============================================================ */
.hero-layer {
  position: relative;
  z-index: 10;
  min-height: 45vh;
  background: #161616;
  overflow: hidden;
  box-shadow: 0 8px 40px rgba(0,0,0,0.7), 0 2px 8px rgba(0,0,0,0.4);
}

/* Depth layer decorations */
.hero-layer::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    linear-gradient(135deg, rgba(255,255,255,0.03) 0%, transparent 60%),
    linear-gradient(to right, rgba(0,0,0,0.5) 50%, transparent 100%);
  z-index: 1;
  pointer-events: none;
}

.hero-layer::after {
  content: '';
  position: absolute;
  right: -60px;
  bottom: -60px;
  width: 300px;
  height: 300px;
  background: rgba(255,255,255,0.02);
  transform: rotate(30deg);
  z-index: 0;
  pointer-events: none;
}

.hero-inner {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: stretch;
  min-height: 45vh;
  max-width: 1280px;
  margin: 0 auto;
}

.hero-media {
  flex: 0 0 55%;
  position: relative;
  overflow: hidden;
}

.hero-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.hero-placeholder {
  width: 100%;
  height: 100%;
  min-height: 45vh;
  background: linear-gradient(135deg, #2a2a2a 0%, #1a1a1a 100%);
}

.hero-text {
  flex: 0 0 45%;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  justify-content: center;
  padding: 48px 48px 48px 40px;
  text-align: right;
  position: relative;
  z-index: 3;
}

.hero-eyebrow {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: rgba(255,255,255,0.45);
  text-transform: uppercase;
  margin-bottom: 12px;
}

.hero-h1 {
  font-size: clamp(1.8rem, 3.5vw, 3rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.15;
  color: #ffffff;
  margin-bottom: 16px;
}

.hero-desc {
  font-size: 1rem;
  color: rgba(255,255,255,0.6);
  line-height: 1.7;
  max-width: 320px;
}

/* ============================================================
   Main Content (main > section.wrap > article > div)
   ============================================================ */
.site-main {
  position: relative;
  z-index: 5;
  flex: 1;
  padding: 0;
}

.wrap {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 40px;
}

.content-section {
  padding: 64px 0;
}

.content-article {
  position: relative;
}

/* ============================================================
   Content Prose (page.content typography)
   ============================================================ */
.content-article h2,
.content-article h3,
.content-article h4 {
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.2;
  margin-top: 2.5em;
  margin-bottom: 0.75em;
  color: #ffffff;
}

.content-article h2 {
  font-size: clamp(1.4rem, 2.5vw, 2rem);
  border-left: 4px solid #ffffff;
  padding-left: 16px;
  margin-left: -20px;
}

.content-article h3 {
  font-size: clamp(1.1rem, 2vw, 1.4rem);
  color: rgba(255,255,255,0.9);
}

.content-article h4 {
  font-size: 1rem;
  color: rgba(255,255,255,0.75);
}

.content-article p {
  font-size: 1rem;
  line-height: 1.8;
  color: rgba(255,255,255,0.78);
  margin-bottom: 1.2em;
}

.content-article ul,
.content-article ol {
  padding-left: 1.4em;
  margin-bottom: 1.2em;
  color: rgba(255,255,255,0.75);
}

.content-article li {
  margin-bottom: 0.4em;
  line-height: 1.7;
}

.content-article a {
  color: #ffffff;
  border-bottom: 1px solid rgba(255,255,255,0.35);
  transition: border-color 0.18s;
}

.content-article a:hover {
  border-bottom-color: #ffffff;
}

.content-article strong {
  color: #ffffff;
  font-weight: 700;
}

.content-article em {
  color: rgba(255,255,255,0.7);
  font-style: italic;
}

.content-article blockquote {
  border-left: 3px solid rgba(255,255,255,0.25);
  padding-left: 20px;
  margin: 1.5em 0;
  color: rgba(255,255,255,0.55);
  font-style: italic;
}

.content-article pre,
.content-article code {
  font-family: 'Courier New', Courier, monospace;
  background: rgba(255,255,255,0.05);
  padding: 2px 6px;
  font-size: 0.9em;
  border-radius: 0;
}

.content-article pre {
  padding: 16px;
  overflow-x: auto;
  margin-bottom: 1.2em;
}

/* ============================================================
   Section Dividers (content blocks inside page.content)
   ============================================================ */
.content-article article {
  position: relative;
  padding: 48px 0;
  border-top: 1px solid rgba(255,255,255,0.07);
}

.content-article article:first-child {
  border-top: none;
  padding-top: 0;
}

/* Dimensional card elevations for article blocks */
.content-article article::before {
  content: '';
  position: absolute;
  left: -40px;
  top: 0;
  bottom: 0;
  width: 3px;
  background: transparent;
  transition: background 0.3s;
}

.content-article article:hover::before {
  background: rgba(255,255,255,0.12);
}

/* Small eyebrow labels */
small {
  display: block;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.4);
  margin-bottom: 8px;
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  position: relative;
  z-index: 5;
  background: #111111;
  border-top: 1px solid rgba(255,255,255,0.06);
  padding: 64px 40px 0;
  margin-top: 80px;
  box-shadow: 0 -4px 40px rgba(0,0,0,0.5);
}

.footer-top {
  max-width: 1280px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  padding-bottom: 48px;
  border-bottom: 1px solid rgba(255,255,255,0.07);
}

.footer-brand__super {
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.35);
  margin-bottom: 8px;
}

.footer-brand__wordmark {
  font-size: clamp(2.5rem, 5vw, 4.5rem);
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1;
  color: #ffffff;
  margin-bottom: 16px;
}

.footer-brand__desc {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.45);
  line-height: 1.7;
  max-width: 320px;
}

.footer-section-label {
  margin-bottom: 20px;
}

.footer-links-col ul {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.footer-links-col ul li a {
  display: block;
  padding: 8px 0;
  font-size: 0.875rem;
  color: rgba(255,255,255,0.55);
  border-bottom: 1px solid transparent;
  transition: color 0.18s, border-color 0.18s;
  min-height: 40px;
  line-height: 1.3;
  display: flex;
  align-items: center;
}

.footer-links-col ul li a:hover {
  color: #ffffff;
  border-bottom-color: rgba(255,255,255,0.2);
}

.footer-bottom {
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 32px;
  padding: 32px 0;
  border-bottom: 1px solid rgba(255,255,255,0.05);
}

.footer-address {
  font-style: normal;
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 0.8rem;
  color: rgba(255,255,255,0.35);
}

.footer-address a {
  color: rgba(255,255,255,0.5);
  transition: color 0.18s;
}

.footer-address a:hover {
  color: #ffffff;
}

.footer-legal {
  display: flex;
  gap: 20px;
  flex-shrink: 0;
}

.footer-legal li a {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.35);
  transition: color 0.18s;
  min-height: 40px;
  display: flex;
  align-items: center;
}

.footer-legal li a:hover {
  color: #ffffff;
}

.footer-copyright {
  max-width: 1280px;
  margin: 0 auto;
  padding: 20px 0 32px;
  font-size: 0.75rem;
  color: rgba(255,255,255,0.2);
}

/* ============================================================
   Dimensional Elevation Utility Classes
   ============================================================ */
.elev-1 {
  box-shadow: 0 1px 4px rgba(0,0,0,0.4);
}
.elev-2 {
  box-shadow: 0 4px 16px rgba(0,0,0,0.5), 0 1px 4px rgba(0,0,0,0.3);
}
.elev-3 {
  box-shadow: 0 8px 32px rgba(0,0,0,0.6), 0 2px 8px rgba(0,0,0,0.4);
}
.elev-4 {
  box-shadow: 0 16px 64px rgba(0,0,0,0.7), 0 4px 16px rgba(0,0,0,0.5);
}

/* ============================================================
   Stagger Animation
   ============================================================ */
@media (prefers-reduced-motion: no-preference) {
  .nav-link {
    transition: color 0.18s, border-color 0.18s, transform 0.18s;
  }
  .nav-link:hover {
    transform: translateY(-1px);
  }

  .btn-cta {
    transition: background 0.18s, color 0.18s, transform 0.18s, box-shadow 0.18s;
  }
  .btn-cta:hover {
    box-shadow: 0 4px 20px rgba(255,255,255,0.15);
  }

  .content-article article {
    transition: box-shadow 0.22s;
  }
  .content-article article:hover {
    box-shadow: inset 0 0 0 1px rgba(255,255,255,0.05);
  }

  /* Stagger list for nav */
  .sticky-nav li {
    animation: fadeSlideIn 0.35s both;
  }
  .sticky-nav li:nth-child(1) { animation-delay: 0.05s; }
  .sticky-nav li:nth-child(2) { animation-delay: 0.10s; }
  .sticky-nav li:nth-child(3) { animation-delay: 0.15s; }
  .sticky-nav li:nth-child(4) { animation-delay: 0.20s; }
  .sticky-nav li:nth-child(5) { animation-delay: 0.25s; }
  .sticky-nav li:nth-child(6) { animation-delay: 0.30s; }
  .sticky-nav li:nth-child(7) { animation-delay: 0.35s; }

  @keyframes fadeSlideIn {
    from {
      opacity: 0;
      transform: translateY(6px);
    }
    to {
      opacity: 1;
      transform: translateY(0);
    }
  }

  /* Hero parallax depth */
  .hero-layer {
    transition: box-shadow 0.3s;
  }
}

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

/* ============================================================
   Responsive — Tablet
   ============================================================ */
@media (max-width: 900px) {
  .brand-bar {
    padding: 14px 24px;
  }

  .sticky-nav ul {
    padding: 0 24px;
  }

  .hero-inner {
    flex-direction: column;
    min-height: auto;
  }

  .hero-media {
    flex: none;
    width: 100%;
    height: 220px;
  }

  .hero-placeholder {
    min-height: 220px;
  }

  .hero-text {
    flex: none;
    padding: 32px 24px;
    align-items: flex-start;
    text-align: left;
  }

  .hero-desc {
    max-width: none;
  }

  .wrap {
    padding: 0 24px;
  }

  .content-article h2 {
    margin-left: 0;
  }

  .footer-top {
    grid-template-columns: 1fr;
    gap: 40px;
    padding-bottom: 40px;
  }

  .site-footer {
    padding: 48px 24px 0;
    margin-top: 60px;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 20px;
  }

  .footer-brand__wordmark {
    font-size: 2.5rem;
  }
}

/* ============================================================
   Responsive — Mobile 375px
   ============================================================ */
@media (max-width: 600px) {
  .brand-bar {
    padding: 12px 16px;
    gap: 12px;
  }

  .brand-bar__wordmark,
  .brand-bar__name {
    font-size: 1.1rem;
  }

  .btn-cta {
    padding: 10px 16px;
    font-size: 0.8rem;
  }

  .sticky-nav ul {
    padding: 0 16px;
    gap: 0;
  }

  .nav-link {
    padding: 12px 12px;
    font-size: 0.78rem;
  }

  .hero-layer {
    min-height: auto;
  }

  .hero-text {
    padding: 24px 16px;
  }

  .hero-h1 {
    font-size: 1.6rem;
  }

  .hero-eyebrow {
    font-size: 0.68rem;
  }

  .hero-desc {
    font-size: 0.9rem;
  }

  .btn-cta--hero {
    padding: 12px 24px;
    font-size: 0.9rem;
    width: 100%;
    text-align: center;
  }

  .wrap {
    padding: 0 16px;
  }

  .content-section {
    padding: 40px 0;
  }

  .content-article h2 {
    font-size: 1.25rem;
    margin-left: 0;
    padding-left: 12px;
  }

  .content-article article {
    padding: 32px 0;
  }

  .content-article article::before {
    left: -16px;
  }

  .site-footer {
    padding: 40px 16px 0;
    margin-top: 40px;
  }

  .footer-top {
    gap: 32px;
    padding-bottom: 32px;
  }

  .footer-brand__wordmark {
    font-size: 2rem;
  }

  .footer-bottom {
    padding: 24px 0;
  }

  .footer-legal {
    gap: 12px;
    flex-wrap: wrap;
  }

  article[id] {
    scroll-margin-top: 90px;
  }
}

button[aria-expanded]{min-width:44px;min-height:44px}