/* 学长 — 3D cat page */
:root{
  --cream:#FBF3E7;
  --cream-2:#F6E7D2;
  --ink:#3B2E26;
  --ink-2:#7C6B5C;
  --warm:#C87A4E;
  --warm-soft:#E7B48C;
  --card:rgba(255,253,249,.78);
  --line:rgba(59,46,38,.10);
  --shadow:0 1px 2px rgba(59,46,38,.05), 0 3px 9px rgba(59,46,38,.045);
  --safe-t:env(safe-area-inset-top, 0px);
  --safe-b:env(safe-area-inset-bottom, 0px);
  --safe-l:env(safe-area-inset-left, 0px);
  --safe-r:env(safe-area-inset-right, 0px);
  --pad:16px;
}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{margin:0;padding:0;height:100%}
html{-webkit-text-size-adjust:100%}
body{
  background:var(--cream);
  color:var(--ink);
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  -webkit-font-smoothing:antialiased;
  overflow:hidden;
  overscroll-behavior:none;
  touch-action:manipulation;
}
body.no-scroll{position:fixed;inset:0;width:100%}

#app{
  position:fixed;inset:0;
  display:grid;
  grid-template-rows:auto minmax(0,1fr) auto auto auto;
  padding:
    calc(var(--safe-t) + 10px)
    max(var(--pad), var(--safe-r))
    calc(var(--safe-b) + 8px)
    max(var(--pad), var(--safe-l));
  z-index:1;
}
#app::before{
  content:"";position:fixed;inset:0;pointer-events:none;z-index:-1;
  background:
    radial-gradient(120% 80% at 50% 22%, #FFF9F0 0%, #FBF3E7 42%, #F4E3CD 100%);
}

/* ---------- top bar ---------- */
.topbar{
  display:grid;grid-template-columns:40px minmax(0,1fr) 40px;
  align-items:start;gap:8px;
}
.icon-btn{
  -webkit-appearance:none;appearance:none;
  display:inline-flex;align-items:center;justify-content:center;
  width:40px;height:40px;padding:0;margin:0;
  border-radius:50%;
  border:1px solid var(--line);
  background:var(--card);
  color:var(--ink);
  box-shadow:var(--shadow);
  cursor:pointer;
  text-decoration:none;
  transition:transform .16s ease, background .16s ease;
  -webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);
}
.icon-btn:active{transform:scale(.94)}
.icon-btn svg{width:22px;height:22px;display:block}
#backBtn svg{width:24px;height:24px;margin-left:-1px}
#soundBtn .ico-off{display:none}
#soundBtn[aria-pressed="false"] .ico-off{display:block}
#soundBtn[aria-pressed="false"] .ico-on{display:none}

.titles{text-align:center;padding-top:1px;overflow:hidden}
.titles h1{
  margin:0;font-size:clamp(19px,5.4vw,25px);font-weight:600;
  letter-spacing:.14em;text-indent:.14em;line-height:1.25;
  color:var(--ink);
}
.titles .sub{
  margin:4px 0 0;font-size:10.5px;letter-spacing:.12em;
  color:rgba(59,46,38,.42);font-weight:400;
}

/* ---------- stage ---------- */
.stage{position:relative;min-height:0;overflow:hidden}
#gl{
  position:absolute;inset:0;width:100%;height:100%;display:block;
  touch-action:none;
  cursor:grab;
}
#gl.dragging{cursor:grabbing}
#gl.hidden{display:none}

.fallback{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;overflow:hidden}
.fallback[hidden]{display:none}
.fallback img{
  max-width:118%;max-height:100%;width:auto;height:auto;
  will-change:transform;transform:translate3d(0,0,0);
  transition:transform .18s ease-out;
}

/* ---------- hint + bottom ---------- */
.hint{
  margin:0 0 10px;text-align:center;
  font-size:12px;letter-spacing:.09em;color:rgba(59,46,38,.46);
  transition:opacity .7s ease, transform .7s ease;
}
.hint.gone{opacity:0;transform:translateY(3px)}

.bottom{
  display:flex;align-items:center;justify-content:space-between;gap:8px;
  padding:0 2px;
}
#fileBtn{justify-self:start}
#tiltBtn{justify-self:end}
#tiltBtn.off{display:none}

.pill-btn{
  -webkit-appearance:none;appearance:none;
  display:inline-flex;align-items:center;gap:5px;
  height:32px;padding:0 13px;margin:0;
  border-radius:999px;border:1px solid var(--line);
  background:var(--card);color:var(--ink);
  font-family:inherit;font-size:12.5px;letter-spacing:.06em;
  box-shadow:var(--shadow);cursor:pointer;
  -webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);
  transition:transform .16s ease,opacity .2s ease;
  white-space:nowrap;
  /* nothing may ever paint outside the pill: no stray glyph, no icon overflow */
  overflow:hidden;overflow:clip;isolation:isolate;
}
.pill-btn:active{transform:scale(.95)}
.pill-btn > .pill-ico{flex:0 0 14px;width:14px;height:14px;display:block;opacity:.7}
.pill-btn > .pill-label{display:block;flex:0 1 auto;min-width:0}
.pill-btn svg{width:14px;height:14px;display:block;opacity:.7}

.dots{
  display:inline-flex;align-items:center;gap:3px;
  padding:7px 9px;border-radius:999px;
  background:var(--card);border:1px solid var(--line);box-shadow:var(--shadow);
  -webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);
}
.dot{
  -webkit-appearance:none;appearance:none;
  width:22px;height:22px;padding:0;margin:0;border:0;background:none;
  display:inline-flex;align-items:center;justify-content:center;cursor:pointer;
}
.dot::before{
  content:"";display:block;width:7px;height:7px;border-radius:999px;
  background:rgba(59,46,38,.24);
  transition:width .24s cubic-bezier(.2,.8,.2,1), background .24s ease;
}
.dot[aria-selected="true"]::before{width:19px;background:var(--warm)}
.dot:focus-visible{outline:2px solid var(--warm);outline-offset:1px;border-radius:999px}

.credit{
  margin:7px 0 0;text-align:center;
  font-size:9.5px;letter-spacing:.03em;color:rgba(59,46,38,.34);
}
.noscript{margin:10px 0;text-align:center;font-size:13px;color:var(--ink-2)}

/* ---------- archive sheet ---------- */
.sheet-mask{
  position:fixed;inset:0;z-index:20;
  background:rgba(48,36,26,.30);
  -webkit-backdrop-filter:blur(3px);backdrop-filter:blur(3px);
  opacity:0;transition:opacity .26s ease;
}
.sheet-mask[hidden]{display:none}
.sheet-mask.open{opacity:1}

.sheet{
  position:fixed;z-index:21;left:0;right:0;bottom:0;
  background:#FFFDF9;
  border-radius:22px 22px 0 0;
  padding:24px 22px calc(26px + var(--safe-b));
  box-shadow:0 -18px 50px rgba(59,46,38,.16);
  transform:translate3d(0,102%,0);
  transition:transform .34s cubic-bezier(.22,.85,.24,1);
  max-height:82vh;max-height:82dvh;overflow-y:auto;
  -webkit-overflow-scrolling:touch;
  visibility:hidden;
}
.sheet[aria-hidden="false"]{transform:translate3d(0,0,0);visibility:visible}
.sheet::before{
  content:"";position:absolute;top:8px;left:50%;transform:translateX(-50%);
  width:36px;height:4px;border-radius:999px;background:rgba(59,46,38,.13);
}
.sheet-close{
  position:sticky;top:0;float:right;
  -webkit-appearance:none;appearance:none;
  width:34px;height:34px;margin:-8px -8px 0 0;padding:0;
  display:inline-flex;align-items:center;justify-content:center;
  border:0;border-radius:50%;background:rgba(59,46,38,.055);color:var(--ink-2);
  cursor:pointer;
}
.sheet-close svg{width:18px;height:18px}
.sheet h2{
  margin:6px 0 0;font-size:22px;font-weight:600;letter-spacing:.1em;
}
.sheet-lead{margin:6px 0 18px;font-size:12.5px;color:var(--ink-2);letter-spacing:.02em}
.facts{margin:0;padding:0}
.facts > div{
  display:grid;grid-template-columns:76px minmax(0,1fr);gap:12px;
  padding:11px 0;border-top:1px solid var(--line);
}
.facts dt{margin:0;font-size:12px;color:rgba(59,46,38,.45);letter-spacing:.08em}
.facts dd{margin:0;font-size:13.5px;color:var(--ink);letter-spacing:.03em}
.facts dd.todo{color:rgba(59,46,38,.38)}
.sheet-note{margin:16px 0 0;font-size:11.5px;line-height:1.7;color:rgba(59,46,38,.45)}

@media (min-width:720px){
  :root{--pad:22px}
  .sheet{
    left:50%;right:auto;bottom:auto;top:50%;width:420px;
    transform:translate3d(-50%,-46%,0) scale(.97);
    border-radius:22px;opacity:0;
    transition:transform .3s cubic-bezier(.22,.85,.24,1), opacity .26s ease;
    max-height:80vh;padding-bottom:28px;
  }
  .sheet[aria-hidden="false"]{transform:translate3d(-50%,-50%,0) scale(1);opacity:1}
  .sheet::before{display:none}
  .hint{font-size:12.5px;margin-bottom:12px}
}

@media (max-height:600px){
  .hint{margin-bottom:6px}
  .credit{display:none}
}

@media (prefers-reduced-motion:reduce){
  *{transition-duration:.01ms !important;animation-duration:.01ms !important}
}