:root{--bg:#0b1020;--panel:#141a32;--ink:#eef2ff;--muted:#9aa3c7;
--accent:#7aa2ff;--line:#2a3260;}
*{box-sizing:border-box}
html,body{margin:0;padding:0;background:var(--bg);color:var(--ink);
  font-family:"Hiragino Sans","Helvetica Neue",Arial,sans-serif;
  -webkit-font-smoothing:antialiased;overflow:hidden;height:100vh;width:100vw}
.deck{position:fixed;inset:0;display:flex;align-items:center;justify-content:center}
img.slide{display:none;max-width:100vw;max-height:100vh;width:auto;height:auto;
  object-fit:contain;user-select:none;-webkit-user-drag:none}
img.slide.active{display:block}
.hud{position:fixed;right:14px;bottom:12px;display:flex;gap:6px;align-items:center;
  background:rgba(20,26,50,.78);border:1px solid var(--line);
  padding:4px 10px;border-radius:999px;font-size:14px;color:var(--muted);
  backdrop-filter:blur(8px);z-index:50}
.hud button{background:transparent;border:0;color:var(--ink);font-size:20px;
  width:36px;height:36px;cursor:pointer;border-radius:50%;line-height:1}
.hud button:active,.hud button:hover{background:#1d2550}
#counter{padding:0 8px;font-variant-numeric:tabular-nums;min-width:64px;text-align:center}
.back-link{position:fixed;left:12px;top:12px;z-index:60;
  display:inline-flex;align-items:center;gap:4px;
  background:rgba(20,26,50,.78);border:1px solid var(--line);
  padding:8px 14px;border-radius:999px;font-size:14px;color:var(--ink);
  text-decoration:none;backdrop-filter:blur(8px);min-height:36px}
.back-link:hover,.back-link:active{background:#1d2550;color:var(--accent)}
.tit{position:fixed;left:50%;bottom:16px;transform:translateX(-50%);
  color:var(--muted);font-size:13px;
  background:rgba(20,26,50,.78);border:1px solid var(--line);
  padding:4px 12px;border-radius:999px;backdrop-filter:blur(8px);
  max-width:60vw;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;
  pointer-events:none;z-index:40}
#toc{position:fixed;inset:0;background:rgba(8,12,30,.94);display:none;
  align-items:center;justify-content:center;z-index:80;padding:48px 16px;overflow:auto}
#toc.show{display:flex}
#toc ol{max-width:760px;width:100%;background:var(--panel);border:1px solid var(--line);
  border-radius:14px;padding:20px 28px 20px 56px;margin:0;font-size:17px;line-height:2}
#toc li{cursor:pointer;color:var(--ink);padding:2px 0}
#toc li:hover{color:var(--accent)}