/* ============================================================
   流浪地球宇宙 · Clean (A24-inspired) — shared styles
   used by *-clean.html pages
   ============================================================ */

/* ============ FONTS ============ */
@font-face{font-family:'Rajdhani';src:url('font/Rajdhani-Light-6.ttf') format('truetype');font-weight:300;font-display:swap;}
@font-face{font-family:'Rajdhani';src:url('font/Rajdhani-Regular-2.ttf') format('truetype');font-weight:400;font-display:swap;}
@font-face{font-family:'Rajdhani';src:url('font/Rajdhani-Medium-3.ttf') format('truetype');font-weight:500;font-display:swap;}
@font-face{font-family:'Rajdhani';src:url('font/Rajdhani-SemiBold-5.ttf') format('truetype');font-weight:600;font-display:swap;}
@font-face{font-family:'Rajdhani';src:url('font/Rajdhani-Bold-4.ttf') format('truetype');font-weight:700;font-display:swap;}
@font-face{font-family:'ZiHunChuangZhongHei';src:url('font/字魂创中黑.ttf') format('truetype');font-weight:400 900;font-display:swap;}

/* ============ TOKENS ============ */
:root{
  --bg:#ffffff;
  --fg:#0a0a0a;
  --muted:#9a9a9a;
  --border:#e6e6e6;
  --font-sans:'Rajdhani',sans-serif;
  --font-mono:'Rajdhani',sans-serif;
  --font-zh:'ZiHunChuangZhongHei','PingFang SC','Hiragino Sans GB','Microsoft YaHei',sans-serif;
  --max-w:1440px;
  --pad-x:48px;
  --ease:cubic-bezier(0.25,0.1,0.25,1);
}

*,*::before,*::after{box-sizing:border-box;}
html,body{margin:0;padding:0;background:var(--bg);color:var(--fg);}
body{
  font-family:var(--font-zh);
  font-size:14px;
  line-height:1.5;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
a{color:inherit;text-decoration:none;}
img{display:block;max-width:100%;}
button{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer;}
::selection{background:var(--fg);color:var(--bg);}

/* ============ NAV ============ */
.nav{
  position:fixed;top:0;left:0;right:0;
  height:72px;
  background:var(--bg);
  z-index:50;
  display:grid;
  grid-template-columns:1fr auto 1fr;
  align-items:center;
  padding:0 var(--pad-x);
  transition:transform .35s var(--ease),background .35s var(--ease),color .35s var(--ease);
}
.nav.is-hidden{transform:translateY(-100%);}
.nav.is-over-hero{background:transparent;color:#fff;}
.nav.is-over-hero .nav-hamburger span{background:#fff;}
.nav.is-over-hero .nav-logo .en{color:rgba(255,255,255,0.65);}
.nav.is-over-hero .nav-right .login{color:#fff;}
.nav.is-over-hero .nav-search-icon::before{border-color:#fff;}
.nav.is-over-hero .nav-search-icon::after{background:#fff;}

.nav-left{
  display:flex;align-items:center;gap:18px;
  font-family:var(--font-mono);
  font-size:12px;
  font-weight:600;
  letter-spacing:0.14em;
}
.nav-hamburger{
  display:inline-flex;flex-direction:column;justify-content:center;
  gap:7px;
  width:32px;height:32px;
  cursor:pointer;
  background:transparent;
}
.nav-hamburger span{
  display:block;
  width:30px;height:1px;background:var(--fg);
  transition:transform .3s var(--ease),opacity .2s var(--ease),background .35s var(--ease);
}
.nav-hamburger.is-open span:nth-child(1){transform:translateY(4px) rotate(45deg);}
.nav-hamburger.is-open span:nth-child(2){transform:translateY(-4px) rotate(-45deg);}
.nav-logo{
  font-family:var(--font-zh);
  font-size:16px;
  font-weight:700;
  letter-spacing:0.02em;
  text-align:center;
}
.nav-logo .en{
  display:block;
  font-family:var(--font-mono);
  font-size:9px;
  font-weight:500;
  letter-spacing:0.28em;
  color:var(--muted);
  margin-top:2px;
  transition:color .35s var(--ease);
}
.nav-right{
  display:flex;justify-content:flex-end;align-items:center;gap:18px;
  font-family:var(--font-mono);
  font-size:12px;
  font-weight:600;
  letter-spacing:0.14em;
}
.nav-right .login{
  color:var(--fg);
  transition:opacity .2s var(--ease),color .35s var(--ease);
}
.nav-right .login:hover{opacity:.55;}
.nav-search-icon{
  width:16px;height:16px;
  position:relative;
  cursor:pointer;
}
.nav-search-icon::before{
  content:"";position:absolute;
  top:0;left:0;width:12px;height:12px;
  border:1.5px solid var(--fg);border-radius:50%;
  transition:border-color .35s var(--ease);
}
.nav-search-icon::after{
  content:"";position:absolute;
  top:11px;left:11px;width:6px;height:1.5px;
  background:var(--fg);transform:rotate(45deg);transform-origin:left center;
  transition:background .35s var(--ease);
}

/* ============ SLIDE MENU ============ */
.menu-mask{
  position:fixed;inset:0;
  background:rgba(0,0,0,0.3);
  opacity:0;pointer-events:none;
  z-index:90;
  transition:opacity .4s var(--ease);
}
.menu-mask.is-open{opacity:1;pointer-events:auto;}
.menu-panel{
  position:fixed;top:0;left:0;bottom:0;
  width:min(420px,86vw);
  background:#0a0a0a;
  color:#fff;
  z-index:100;
  padding:32px 40px 40px;
  transform:translateX(-100%);
  transition:transform .45s var(--ease);
  display:flex;flex-direction:column;
}
.menu-panel.is-open{transform:translateX(0);}
.menu-head{
  display:flex;justify-content:space-between;align-items:center;
  height:40px;
  margin-bottom:64px;
}
.menu-label{
  font-family:var(--font-mono);
  font-size:12px;
  font-weight:600;
  letter-spacing:0.18em;
  text-transform:uppercase;
  color:#888;
}
.menu-close{
  width:32px;height:32px;
  position:relative;
  cursor:pointer;
}
.menu-close::before,.menu-close::after{
  content:"";position:absolute;
  top:50%;left:50%;width:30px;height:1px;
  background:#fff;
  transform-origin:center;
}
.menu-close::before{transform:translate(-50%,-50%) rotate(45deg);}
.menu-close::after{transform:translate(-50%,-50%) rotate(-45deg);}

.menu-links{
  display:flex;flex-direction:column;
  gap:18px;
  flex:1;
}
.menu-link{
  font-family:var(--font-sans);
  font-size:44px;
  font-weight:700;
  letter-spacing:-0.02em;
  line-height:1.05;
  color:#fff;
  transition:color .2s var(--ease),padding-left .35s var(--ease);
  display:inline-flex;align-items:baseline;gap:16px;
  width:max-content;
}
.menu-link .zh{
  font-family:var(--font-zh);
  font-weight:700;
  font-size:0.55em;
  color:#666;
  letter-spacing:0;
  transition:color .2s var(--ease);
}
.menu-link:hover{padding-left:14px;}
.menu-link:hover .zh{color:#fff;}

.menu-foot{
  display:flex;justify-content:space-between;align-items:flex-end;
  gap:24px;
  padding-top:32px;
  border-top:1px solid #222;
  font-family:var(--font-mono);
  font-size:10px;
  font-weight:500;
  letter-spacing:0.22em;
  text-transform:uppercase;
  color:#666;
}
.menu-foot a{color:#888;transition:color .2s var(--ease);}
.menu-foot a:hover{color:#fff;}

/* ============ HERO CAROUSEL ============ */
.hero{
  position:relative;
  height:100vh;
  min-height:560px;
  max-height:960px;
  overflow:hidden;
  background:#0a0a0a;
}
.hero-slide{
  position:absolute;inset:0;
  opacity:0;
  transition:opacity 1.2s var(--ease);
  pointer-events:none;
}
.hero-slide.is-active{opacity:1;pointer-events:auto;}
.hero-slide img{
  position:absolute;inset:0;
  width:100%;height:100%;
  object-fit:cover;
  object-position:center 42%;
  transform:scale(1.03);
  transition:transform 7s linear;
}
.hero-slide.is-active img{transform:scale(1);}
.hero-veil{
  position:absolute;inset:0;
  background:linear-gradient(180deg, rgba(0,0,0,0.25) 0%, transparent 35%, transparent 60%, rgba(0,0,0,0.55) 100%);
  pointer-events:none;
}

/* page-hero: same chrome as hero but with overlaid title (single image, no carousel) */
.hero--page{height:80vh;min-height:520px;max-height:780px;}
.hero-title-overlay{
  position:absolute;
  left:var(--pad-x);bottom:120px;
  right:var(--pad-x);
  color:#fff;z-index:3;
}
.hero-title-overlay .eyebrow{
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:0.32em;
  text-transform:uppercase;
  color:rgba(255,255,255,0.7);
  margin-bottom:24px;
  display:flex;align-items:center;gap:14px;
}
.hero-title-overlay .eyebrow a{color:rgba(255,255,255,0.7);transition:color .2s var(--ease);}
.hero-title-overlay .eyebrow a:hover{color:#fff;}
.hero-title-overlay h1{
  font-family:var(--font-zh);
  font-size:clamp(56px,8vw,128px);
  font-weight:700;
  letter-spacing:-0.02em;
  line-height:0.94;
  margin:0;
  max-width:18ch;
}
.hero-title-overlay h1 .en{
  display:block;
  font-family:var(--font-sans);
  font-size:0.32em;
  font-weight:700;
  letter-spacing:-0.005em;
  color:rgba(255,255,255,0.7);
  margin-top:20px;
}

.hero-caption{
  position:absolute;
  left:var(--pad-x);bottom:36px;
  color:#fff;z-index:3;
  display:flex;align-items:baseline;gap:18px;
  font-family:var(--font-mono);
  font-size:11px;font-weight:500;
  letter-spacing:0.22em;text-transform:uppercase;
}
.hero-caption .index{
  color:rgba(255,255,255,0.55);
  font-variant-numeric:tabular-nums;
}
.hero-caption .title{
  font-family:var(--font-zh);
  font-size:13px;font-weight:500;
  letter-spacing:0.02em;text-transform:none;color:#fff;
  transition:opacity .4s var(--ease);
}
.hero-dots{
  position:absolute;
  right:var(--pad-x);bottom:36px;
  z-index:3;
  display:flex;gap:14px;align-items:center;
}
.hero-dot{
  width:28px;height:1px;
  background:rgba(255,255,255,0.32);
  cursor:pointer;
  position:relative;
  overflow:hidden;
  transition:background .3s var(--ease);
}
.hero-dot:hover{background:rgba(255,255,255,0.55);}
.hero-dot.is-active{background:rgba(255,255,255,0.32);}
.hero-dot.is-active::after{
  content:"";position:absolute;
  top:0;left:0;height:100%;width:0;
  background:#fff;
  animation:dotFill var(--slide-dur,5s) linear forwards;
}
@keyframes dotFill{from{width:0;}to{width:100%;}}

/* ============ SECTION SHELL ============ */
.section{
  padding:80px var(--pad-x) 40px;
  max-width:var(--max-w);
  margin:0 auto;
}
.section--first{padding-top:48px;}
.section--tight{padding-top:32px;padding-bottom:24px;}

.section-title{
  font-family:var(--font-sans);
  font-size:clamp(40px,5vw,72px);
  font-weight:800;
  letter-spacing:-0.025em;
  line-height:1;
  margin:0 0 64px;
  display:flex;
  align-items:baseline;
  justify-content:space-between;
  gap:32px;
}
.section-title .zh{
  font-family:var(--font-zh);
  font-weight:700;
  letter-spacing:-0.01em;
}
.section-title-right{
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:0.18em;
  text-transform:uppercase;
  color:var(--muted);
  display:flex;align-items:baseline;gap:18px;
  white-space:nowrap;
}
.section-title-right .label{color:var(--muted);}
.section-title-right a{
  color:var(--muted);
  position:relative;
  padding-bottom:2px;
  transition:color .2s var(--ease);
}
.section-title-right a:hover{color:var(--fg);}
.section-title-right a.active{color:var(--fg);border-bottom:1px solid var(--fg);}

/* ============ MASONRY GRID ============ */
.grid{
  column-count:3;
  column-gap:32px;
}
.grid-item{
  break-inside:avoid;
  margin-bottom:96px;
  display:block;
}
.grid-item-img{
  width:100%;overflow:hidden;
  background:#f3f3f3;
  margin-bottom:18px;
}
.grid-item-img img{
  width:100%;height:100%;
  object-fit:cover;
  transition:opacity .35s var(--ease),transform 1.2s var(--ease);
}
.grid-item:hover .grid-item-img img{
  opacity:.78;
  transform:scale(1.02);
}
.grid-item-tag{
  font-family:var(--font-mono);
  font-size:10px;
  font-weight:500;
  letter-spacing:0.22em;
  text-transform:uppercase;
  color:var(--muted);
  margin-bottom:6px;
}
.grid-item-title{
  font-family:var(--font-zh);
  font-size:22px;
  font-weight:600;
  line-height:1.25;
  letter-spacing:-0.005em;
  margin:0;
  color:var(--fg);
  text-wrap:pretty;
  max-width:24ch;
}
.grid-item-title .en{
  display:block;
  font-family:var(--font-sans);
  font-weight:600;
  font-size:0.85em;
  color:var(--muted);
  margin-top:2px;
  letter-spacing:0.005em;
}

.ar-3-2  .grid-item-img{aspect-ratio:3/2;}
.ar-2-3  .grid-item-img{aspect-ratio:2/3;}
.ar-4-5  .grid-item-img{aspect-ratio:4/5;}
.ar-5-4  .grid-item-img{aspect-ratio:5/4;}
.ar-1-1  .grid-item-img{aspect-ratio:1/1;}
.ar-16-9 .grid-item-img{aspect-ratio:16/9;}

/* ============ FOOTER ============ */
.footer{
  margin-top:80px;
  padding:48px var(--pad-x) 40px;
  max-width:var(--max-w);
  margin-left:auto;margin-right:auto;
  display:flex;
  justify-content:space-between;
  align-items:flex-end;
  gap:48px;
  font-family:var(--font-mono);
  font-size:10px;
  font-weight:500;
  letter-spacing:0.22em;
  text-transform:uppercase;
  color:var(--muted);
}
.footer-left{display:flex;flex-direction:column;gap:6px;}
.footer-left .zh{
  font-family:var(--font-zh);
  font-size:11px;font-weight:500;
  letter-spacing:0.02em;text-transform:none;color:var(--fg);
}
.footer-links{display:flex;gap:24px;}
.footer-links a{color:var(--muted);transition:color .2s var(--ease);}
.footer-links a:hover{color:var(--fg);}
.footer-right{text-align:right;}

/* ============ BACK TO TOP ============ */
.to-top{
  position:fixed;
  right:var(--pad-x);
  bottom:40px;
  z-index:60;
  width:48px;
  height:48px;
  display:flex;
  align-items:center;
  justify-content:center;
  background:var(--bg);
  color:var(--fg);
  border:1px solid var(--border);
  opacity:0;
  visibility:hidden;
  transform:translateY(12px);
  transition:opacity .35s var(--ease),transform .35s var(--ease),visibility .35s var(--ease),background .25s var(--ease),color .25s var(--ease);
}
.to-top.is-visible{opacity:1;visibility:visible;transform:translateY(0);}
.to-top:hover{background:var(--fg);color:var(--bg);}
.to-top svg{
  width:18px;height:18px;
  fill:none;
  stroke:currentColor;
  stroke-width:1.5;
  stroke-linecap:square;
  stroke-linejoin:miter;
}

/* ============ RESPONSIVE ============ */
@media (max-width:960px){
  :root{--pad-x:24px;}
  .grid{column-count:2;column-gap:20px;}
  .grid-item{margin-bottom:64px;}
  .grid-item-title{font-size:18px;}
  .section{padding:56px var(--pad-x) 24px;}
  .section-title{margin-bottom:48px;}
  .nav-right .login{display:none;}
  .hero-title-overlay{bottom:96px;}
  .hero-title-overlay h1{font-size:clamp(40px,9vw,80px);}
}
@media (max-width:600px){
  .grid{column-count:1;}
  .section-title{font-size:36px;flex-direction:column;align-items:flex-start;gap:16px;}
  .footer{flex-direction:column;align-items:flex-start;}
  .footer-right{text-align:left;}
  .hero{height:80vh;min-height:420px;}
  .hero-caption{font-size:10px;gap:12px;flex-direction:column;}
  .to-top{width:44px;height:44px;bottom:24px;}
  .hero-caption .title{font-size:12px;}
  .hero-dots{gap:10px;}
  .hero-dot{width:20px;}
}