:root {
  --gold: #C5A455; --gold-light: #D4B86A; --gold-dark: #A8883C;
  --ivory: #FFF8F0; --cream: #F5EDE0; --ebony: #1A1410;
  --brown-dark: #2C1810; --brown-mid: #4A3020; --brown-light: #6B5040;
  --border: rgba(197,164,85,0.18);
  --font-h: 'Playfair Display','Noto Serif SC',Georgia,serif;
  --font-body: 'Inter',-apple-system,sans-serif;
  --font-zh: 'Noto Serif SC','SimSun',serif;
}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html,body{width:100%;height:100%;overflow:hidden}
body{font-family:var(--font-body);background:var(--ebony);color:var(--ivory);-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
button{background:none;border:none;cursor:pointer;font-family:inherit;color:inherit}
.en{font-family:var(--font-body);font-weight:400}
html[lang="zh"] .en{display:none!important}
html[lang="en"] .zh{display:none!important}

.lang-toggle{
  position:fixed;top:12px;right:20px;z-index:2001;
  display:flex;align-items:center;gap:3px;
  font-size:0.7rem;letter-spacing:0.08em;
  color:rgba(255,248,240,0.5);cursor:pointer;
  padding:4px 10px;border:1px solid rgba(197,164,85,0.15);border-radius:3px;
  backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px);transition:all 0.3s;
  font-family:var(--font-body);background:rgba(26,20,16,0.4);
}
.lang-toggle:hover{border-color:rgba(197,164,85,0.35);color:var(--gold)}
.lang-toggle .lang-opt{padding:0 2px;transition:color 0.3s}
.lang-toggle .lang-opt.active{color:var(--gold);font-weight:600}
.lang-divider{opacity:0.3;font-size:0.6rem}

.nav-bar{
  position:fixed;top:0;left:0;right:0;z-index:2000;height:48px;
  display:flex;align-items:center;justify-content:space-between;
  padding:0 16px;background:rgba(26,20,16,0.88);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);
  border-bottom:1px solid rgba(197,164,85,0.06);
}
.nav-bar .nav-title{display:flex;align-items:center;gap:7px;font-size:0.82rem;color:var(--gold);font-family:var(--font-zh)}
.nav-bar .nav-title .td{display:flex;gap:2px;align-items:center}
.nav-bar .nav-title .td span{width:4px;height:4px;border-radius:50%;background:var(--gold);display:block;opacity:0.5}
.nav-bar .back-link{font-size:0.72rem;color:rgba(255,248,240,0.45);transition:color 0.3s;display:flex;align-items:center;gap:5px}
.nav-bar .back-link:hover{color:var(--gold)}

canvas#rockCanvas{display:block;position:fixed;top:48px;left:0;right:0;bottom:56px;width:100%;z-index:1}

.toolbar{
  position:fixed;bottom:0;left:0;right:0;z-index:2000;
  height:56px;background:rgba(26,20,16,0.92);backdrop-filter:blur(12px);-webkit-backdrop-filter:blur(12px);
  border-top:1px solid rgba(197,164,85,0.06);
  display:flex;align-items:center;justify-content:center;gap:4px;padding:0 12px;
}
.tool-btn{
  display:flex;flex-direction:column;align-items:center;gap:2px;
  padding:6px 14px;border-radius:5px;
  border:1px solid transparent;color:rgba(255,248,240,0.35);
  font-size:0.55rem;letter-spacing:0.04em;
  transition:all 0.25s;min-width:52px;
}
.tool-btn svg{width:20px;height:20px;opacity:0.4;transition:opacity 0.25s}
.tool-btn:hover{color:var(--gold)}
.tool-btn:hover svg{opacity:0.7}
.tool-btn.active{border-color:rgba(197,164,85,0.25);color:var(--gold);background:rgba(197,164,85,0.06)}
.tool-btn.active svg{opacity:1}
.tool-sep{width:1px;height:24px;background:rgba(197,164,85,0.08);margin:0 3px}

.info-overlay{
  position:fixed;top:54px;right:14px;z-index:100;
  display:flex;flex-direction:column;align-items:flex-end;gap:2px;
  pointer-events:none;
}
.info-overlay span{
  font-size:0.6rem;color:rgba(255,248,240,0.18);
  letter-spacing:0.06em;font-family:var(--font-body);
}

.ttip{
  position:fixed;bottom:62px;left:50%;transform:translateX(-50%);
  z-index:500;font-size:0.68rem;color:rgba(255,248,240,0.3);
  letter-spacing:0.06em;text-align:center;pointer-events:none;
  transition:opacity 0.6s;opacity:0;white-space:nowrap;
}

@media(max-width:640px){
  .tool-btn{padding:4px 10px;min-width:40px}
  .tool-btn svg{width:18px;height:18px}
  .tool-btn span{font-size:0.5rem}
  .nav-bar .nav-title{font-size:0.7rem}
  .info-overlay{display:none}
  canvas#rockCanvas{bottom:52px}
  .toolbar{height:52px}
}