:root {
  --bg: #0a0a0a;
  --surface: #111;
  --surface2: #181818;
  --text: #f2f0ed;
  --text2: rgba(242,240,237,0.5);
  --text3: rgba(242,240,237,0.22);
  --accent: #c0a070;
  --accent2: #9a7d56;
  --border: rgba(242,240,237,0.07);
  --radius: 4px;
}

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  line-height: 1.6;
}

body.lang-zh { font-family: 'Noto Serif SC', 'Inter', serif; }

::selection { background: var(--accent); color: var(--bg); }
::-webkit-scrollbar { width: 5px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--surface2); border-radius: 3px; }

img { user-select: none; -webkit-user-drag: none; }

/* NAV */
nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  padding: 0 48px; height: 72px;
  display: flex; align-items: center;
  background: rgba(10,10,10,0.6);
  backdrop-filter: blur(32px) saturate(1.4);
  -webkit-backdrop-filter: blur(32px) saturate(1.4);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  width: 100%; max-width: 1360px; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
}

.logo {
  font-family: 'Cormorant Garamond', 'Noto Serif SC', serif;
  font-size: 20px; font-weight: 500; letter-spacing: 6px;
  text-decoration: none; color: var(--text);
}

.nav-links { display: flex; align-items: center; gap: 36px; }

.nav-links a {
  color: var(--text2); text-decoration: none;
  font-size: 12px; letter-spacing: 2.5px; text-transform: uppercase;
  font-weight: 400; transition: color 0.3s;
}
.nav-links a:hover { color: var(--text); }

.lang-btn {
  background: transparent;
  border: 1px solid rgba(242,240,237,0.12);
  color: var(--text2); width: 32px; height: 32px;
  border-radius: 50%; cursor: pointer;
  font-size: 12px; font-weight: 500;
  font-family: 'Noto Serif SC', serif;
  transition: all 0.3s;
}
.lang-btn:hover {
  border-color: var(--accent); color: var(--accent);
  background: rgba(192,160,112,0.06);
}

/* HERO */
.hero {
  position: relative; width: 100%; height: 100vh; min-height: 680px;
  display: flex; align-items: center; justify-content: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute; inset: 0;
  background-size: cover; background-position: center;
  transform: scale(1.04);
  animation: heroDrift 24s ease-in-out infinite alternate;
}

@keyframes heroDrift {
  0% { transform: scale(1.04) translate(0, 0); }
  100% { transform: scale(1.08) translate(-1%, 0.5%); }
}

.hero-overlay {
  position: absolute; inset: 0;
  background:
    radial-gradient(ellipse at 50% 40%, rgba(10,10,10,0.5) 0%, transparent 70%),
    linear-gradient(180deg, rgba(10,10,10,0.3) 0%, rgba(10,10,10,0.75) 100%);
}

.hero-content {
  position: relative; z-index: 2;
  text-align: center; padding: 0 24px;
  animation: fadeUp 1s ease-out 0.2s both;
}

.hero-eyebrow {
  font-size: 11px; letter-spacing: 5px; text-transform: uppercase;
  color: var(--accent); margin-bottom: 28px; font-weight: 400;
}

.hero-title { margin-bottom: 20px; }

.hero-line {
  display: block;
  font-family: 'Cormorant Garamond', 'Noto Serif SC', serif;
  font-size: clamp(72px, 13vw, 160px);
  font-weight: 300; line-height: 0.9; letter-spacing: 8px;
}

.hero-line.accent {
  font-style: italic; font-weight: 400;
  background: linear-gradient(135deg, #d4b896, var(--accent), #9a7d56);
  background-clip: text; -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-sub {
  font-size: clamp(14px, 1.4vw, 17px);
  color: var(--text2); letter-spacing: 2px; font-weight: 300;
  margin: 0 auto 44px; max-width: 440px;
}

.hero-cta {
  display: inline-block;
  padding: 14px 44px;
  border: 1px solid rgba(242,240,237,0.2);
  font-size: 12px; letter-spacing: 3px;
  text-transform: uppercase; text-decoration: none; color: var(--text);
  transition: all 0.5s cubic-bezier(0.22, 1, 0.36, 1);
  background: transparent;
}
.hero-cta:hover {
  background: var(--text); color: var(--bg);
  border-color: var(--text);
}

.scroll-hint {
  position: absolute; bottom: 36px; left: 50%;
  transform: translateX(-50%); z-index: 2;
  display: flex; flex-direction: column; align-items: center; gap: 10px;
  animation: fadeUp 1s ease-out 0.6s both;
}
.scroll-hint span { font-size: 9px; letter-spacing: 4px; text-transform: uppercase; color: var(--text3); }
.scroll-line {
  width: 1px; height: 36px;
  background: linear-gradient(180deg, var(--text3), transparent);
  animation: pulse 2.5s ease-in-out infinite;
}
@keyframes pulse { 0%, 100% { opacity: 0.3; } 50% { opacity: 1; } }
@keyframes fadeUp { from { opacity: 0; transform: translateY(24px); } to { opacity: 1; transform: translateY(0); } }

.section-eyebrow {
  font-size: 11px; letter-spacing: 4px; text-transform: uppercase;
  color: var(--accent); margin-bottom: 16px; font-weight: 400;
}
.section-eyebrow.light { color: var(--text3); }

/* GALLERY */
.gallery {
  padding: 120px 24px 80px;
  max-width: 1200px;
  margin: 0 auto;
}

.gallery-header {
  margin-bottom: 48px;
  text-align: center;
}

.gallery-header h2 {
  font-family: 'Cormorant Garamond', 'Noto Serif SC', serif;
  font-size: clamp(32px, 4vw, 48px);
  font-weight: 400; letter-spacing: 3px; margin-bottom: 12px;
}

.section-desc {
  color: var(--text2); font-size: 15px; font-weight: 300; letter-spacing: 0.5px;
}

/* BOOK VIEWER */
.book-viewer {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
}

.book-nav {
  background: none;
  border: 1px solid rgba(242,240,237,0.08);
  color: var(--text2);
  width: 44px; height: 44px;
  border-radius: 50%;
  cursor: pointer;
  font-size: 18px;
  flex-shrink: 0;
  transition: all 0.3s;
  display: flex; align-items: center; justify-content: center;
}
.book-nav:hover { border-color: var(--accent); color: var(--accent); }
.book-nav:disabled { opacity: 0.15; cursor: default; border-color: rgba(242,240,237,0.04); }
.book-nav:disabled:hover { border-color: rgba(242,240,237,0.04); color: var(--text2); }

.book-stage {
  flex: 1;
  max-width: 960px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.spread-container {
  position: relative;
  width: 100%;
  min-height: 400px;
}

.spread {
  display: none;
  align-items: stretch;
  background: var(--surface);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 8px 40px rgba(0,0,0,0.35);
  width: 100%;
}

.spread.active {
  display: flex;
  animation: spreadIn 0.5s cubic-bezier(0.22, 1, 0.36, 1);
}

@keyframes spreadIn {
  from { opacity: 0; transform: translateX(20px); }
  to { opacity: 1; transform: translateX(0); }
}

.spread.going-back.active {
  animation-name: spreadInBack;
}

@keyframes spreadInBack {
  from { opacity: 0; transform: translateX(-20px); }
  to { opacity: 1; transform: translateX(0); }
}

.spread-page {
  flex: 1;
  min-width: 0;
}

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

.spine {
  width: 3px;
  background: linear-gradient(180deg,
    rgba(0,0,0,0.6) 0%,
    rgba(0,0,0,0.3) 10%,
    rgba(192,160,112,0.08) 50%,
    rgba(0,0,0,0.3) 90%,
    rgba(0,0,0,0.6) 100%
  );
  flex-shrink: 0;
}

.spread.single {
  max-width: 50%;
  margin: 0 auto;
}
.spread.single .spread-page img {
  aspect-ratio: 1 / 1;
}

/* BOOK FOOTER */
.book-footer {
  margin-top: 20px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  width: 100%;
}

.thumb-strip {
  display: flex;
  gap: 6px;
  justify-content: center;
  flex-wrap: nowrap;
  max-width: 100%;
  overflow-x: auto;
  -ms-overflow-style: none;
  scrollbar-width: none;
}
.thumb-strip::-webkit-scrollbar { display: none; }

.thumb {
  flex-shrink: 0;
  width: 32px; height: 32px;
  border-radius: 2px; overflow: hidden;
  cursor: pointer;
  border: 1.5px solid transparent;
  opacity: 0.3;
  transition: all 0.3s;
  background: var(--surface2);
}
.thumb:hover { opacity: 0.6; }
.thumb.active { border-color: var(--accent); opacity: 1; }
.thumb img { width: 100%; height: 100%; object-fit: cover; }

.page-info {
  font-family: 'Cormorant Garamond', serif;
  font-size: 13px; letter-spacing: 2px; color: var(--text3);
}

/* ABOUT */
.about {
  padding: 128px 48px 140px;
  border-top: 1px solid var(--border);
}

.about-inner {
  max-width: 1360px; margin: 0 auto;
  display: grid; grid-template-columns: 1fr 1fr;
  gap: 80px; align-items: center;
}

.about-left h2 {
  font-family: 'Cormorant Garamond', 'Noto Serif SC', serif;
  font-size: clamp(30px, 3.5vw, 44px);
  font-weight: 400; letter-spacing: 3px; margin-bottom: 20px;
}

.about-rule { width: 40px; height: 1px; background: var(--accent); margin-bottom: 24px; }

.about-left p {
  color: var(--text2); font-size: 15px; line-height: 1.8;
  font-weight: 300; letter-spacing: 0.3px; margin-bottom: 14px;
  max-width: 460px;
}

.about-right {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px;
}

.stat {
  text-align: center; padding: 36px 16px;
  border: 1px solid var(--border); border-radius: var(--radius);
  background: rgba(242,240,237,0.015);
  transition: border-color 0.3s, background 0.3s;
}
.stat:hover { border-color: rgba(242,240,237,0.1); background: rgba(242,240,237,0.03); }

.stat-val {
  display: block;
  font-family: 'Cormorant Garamond', serif;
  font-size: 44px; font-weight: 500; color: var(--accent);
  line-height: 1; margin-bottom: 8px;
}

.stat-key { font-size: 11px; letter-spacing: 2px; text-transform: uppercase; color: var(--text3); }

/* FOOTER */
footer { border-top: 1px solid var(--border); }

.footer-inner {
  max-width: 1360px; margin: 0 auto;
  padding: 28px 48px;
  display: flex; align-items: center; justify-content: space-between;
}

.footer-brand {
  font-family: 'Cormorant Garamond', serif;
  font-size: 14px; letter-spacing: 4px; color: var(--text3);
}

footer p { font-size: 12px; color: var(--text3); letter-spacing: 0.5px; font-weight: 300; }

/* RESPONSIVE */
@media (max-width: 1024px) {
  .about-inner { grid-template-columns: 1fr; gap: 48px; }
}

@media (max-width: 768px) {
  nav { padding: 0 20px; height: 60px; }
  .nav-links { gap: 20px; }
  .gallery { padding: 80px 12px; }
  .book-nav { width: 36px; height: 36px; font-size: 14px; }
  .about { padding: 80px 20px; }
  .about-right { grid-template-columns: repeat(3, 1fr); gap: 12px; }
  .stat { padding: 24px 10px; }
  .stat-val { font-size: 32px; }
  .footer-inner { padding: 20px; flex-direction: column; gap: 6px; }
}

@media (max-width: 540px) {
  .spread { flex-direction: column; }
  .spine { width: auto; height: 2px; background: linear-gradient(90deg, rgba(0,0,0,0.6), rgba(192,160,112,0.08), rgba(0,0,0,0.6)); }
  .spread.single { max-width: 100%; }
  .book-viewer { gap: 8px; }
  .thumb { width: 26px; height: 26px; }
}