/* ==========================================================================
   Books — reading-first UI. Mobile is the primary target; desktop is the
   same layout with a wider column and a persistent table of contents.
   ========================================================================== */

:root{
  --bg:#fbfaf8; --fg:#16181d; --muted:#5f6672; --line:#e3e0da;
  --card:#ffffff; --accent:#5b4bd6; --accent2:#0f8f78; --warn:#b3541e;
  --code:#f2f0ec; --shadow:0 1px 2px rgba(0,0,0,.05),0 8px 24px rgba(0,0,0,.04);
  --bar:rgba(251,250,248,.92);
}
@media (prefers-color-scheme: dark){
  :root{ --bg:#0f1115; --fg:#e8e6e1; --muted:#9aa1ad; --line:#262a33;
    --card:#161a21; --accent:#9d8dff; --accent2:#4fd1b0; --warn:#e2914f;
    --code:#1b1f27; --shadow:none; --bar:rgba(15,17,21,.92); }
}
:root[data-theme="dark"]{ --bg:#0f1115; --fg:#e8e6e1; --muted:#9aa1ad; --line:#262a33;
  --card:#161a21; --accent:#9d8dff; --accent2:#4fd1b0; --warn:#e2914f; --code:#1b1f27;
  --shadow:none; --bar:rgba(15,17,21,.92); }
:root[data-theme="light"]{ --bg:#fbfaf8; --fg:#16181d; --muted:#5f6672; --line:#e3e0da;
  --card:#ffffff; --accent:#5b4bd6; --accent2:#0f8f78; --warn:#b3541e; --code:#f2f0ec;
  --shadow:0 1px 2px rgba(0,0,0,.05),0 8px 24px rgba(0,0,0,.04); --bar:rgba(251,250,248,.92); }

*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:66px}
body{
  margin:0;background:var(--bg);color:var(--fg);overflow-x:hidden;
  font:400 17.5px/1.68 -apple-system,BlinkMacSystemFont,"SF Pro Text","Segoe UI",Roboto,"Helvetica Neue",sans-serif;
  padding:52px 0 84px;
}
.wrap{max-width:44rem;margin:0 auto;padding:0 18px}
a{color:var(--accent);text-decoration:none;border-bottom:1px solid color-mix(in srgb,var(--accent) 32%,transparent)}
p{margin:.75em 0}
ul,ol{padding-left:1.25em;margin:.7em 0}
li{margin:.35em 0}
strong{font-weight:680}
code{background:var(--code);padding:.12em .38em;border-radius:5px;
  font:500 .88em/1.4 ui-monospace,SFMono-Regular,Menlo,monospace;word-break:break-word}
pre{background:var(--code);padding:12px 14px;border-radius:10px;overflow-x:auto}
pre code{background:none;padding:0}
hr{border:0;border-top:1px solid var(--line);margin:1.6em 0}
img{max-width:100%;height:auto}

/* progress ------------------------------------------------------------- */
#prog{position:fixed;top:0;left:0;height:3px;width:0;background:var(--accent);z-index:70;transition:width .1s linear}

/* top bar -------------------------------------------------------------- */
.topbar{
  position:fixed;top:0;left:0;right:0;height:52px;z-index:60;display:flex;align-items:center;gap:8px;
  padding:0 10px;background:var(--bar);backdrop-filter:blur(12px);border-bottom:1px solid var(--line);
}
.tb-btn{
  flex:0 0 auto;width:38px;height:38px;display:grid;place-items:center;font-size:17px;
  background:transparent;border:1px solid var(--line);border-radius:10px;color:var(--fg);cursor:pointer;
}
.tb-title{flex:1;min-width:0;font-weight:650;font-size:15px;text-align:center;
  white-space:nowrap;overflow:hidden;text-overflow:ellipsis;color:var(--muted)}
.tb-book{color:var(--fg)}

/* bottom bar ----------------------------------------------------------- */
.bar{
  position:fixed;bottom:0;left:0;right:0;z-index:60;display:flex;gap:8px;justify-content:center;
  padding:9px 10px calc(9px + env(safe-area-inset-bottom));
  background:var(--bar);backdrop-filter:blur(12px);border-top:1px solid var(--line);
}
.bar button,.bar .btn{
  font:inherit;font-size:14px;font-weight:600;color:var(--fg);background:var(--card);
  border:1px solid var(--line);border-radius:10px;padding:9px 13px;cursor:pointer;
  white-space:nowrap;text-decoration:none;
}
.bar button:active,.bar .btn:active{transform:scale(.97)}

/* drawer --------------------------------------------------------------- */
.drawer{position:fixed;inset:0;z-index:80;background:var(--bg);display:flex;flex-direction:column}
.drawer[hidden]{display:none}
.drawer-head{display:flex;gap:8px;padding:10px 14px calc(10px);border-bottom:1px solid var(--line);
  background:var(--bar);backdrop-filter:blur(12px)}
.drawer-head input{
  flex:1;font:inherit;font-size:16px;padding:10px 12px;border-radius:10px;
  border:1px solid var(--line);background:var(--card);color:var(--fg);min-width:0;
}
.drawer-head .close{font:inherit;font-weight:700;background:var(--card);border:1px solid var(--line);
  border-radius:10px;padding:0 15px;cursor:pointer;color:var(--fg)}
.drawer-body{flex:1;overflow-y:auto;-webkit-overflow-scrolling:touch;padding:14px 16px 90px}
.nav-home{display:block;font-weight:650;margin-bottom:14px;border:none}
.nav-group{margin-bottom:18px}
.nav-group[hidden]{display:none}
.nav-group-head{display:flex;align-items:baseline;gap:8px;border-bottom:1px solid var(--line);padding-bottom:5px;margin-bottom:6px}
.nav-group-head a{font-size:12.5px;letter-spacing:.1em;text-transform:uppercase;font-weight:800;color:var(--accent2);border:none}
.nav-group-head .n{font-size:12px;color:var(--muted)}
.nav-group ul{list-style:none;padding:0;margin:0}
.nav-group li{margin:0}
.nav-group li[hidden]{display:none}
.nav-group li a{display:block;padding:9px 10px;border-radius:9px;border:none;color:var(--fg);font-weight:550;line-height:1.4}
.nav-group li a.cur{background:var(--card);border:1px solid var(--line);color:var(--accent)}
.nav-group li a .meta{display:block;font-size:12.5px;color:var(--muted);font-weight:400}
.draft{font-style:normal;font-size:11px;color:var(--warn);border:1px solid var(--warn);
  border-radius:5px;padding:0 4px;margin-left:5px}
.toc-drawer,.toc-drawer ol{list-style:none;padding-left:0;margin:0}
.toc-drawer > li{margin:.2em 0}
.toc-drawer > li > a{display:block;padding:9px 8px;border:none;color:var(--fg);font-weight:600;border-radius:8px}
.toc-drawer ol{padding-left:12px;border-left:1px solid var(--line);margin:2px 0 8px}
.toc-drawer ol a{display:block;padding:7px 8px;border:none;color:var(--muted);font-size:.94em}
.toc-drawer a.active{background:var(--card);color:var(--accent)}
.find-results{margin-bottom:14px}
.find-results a{display:block;padding:10px;border:1px solid var(--line);border-radius:10px;
  margin-bottom:8px;background:var(--card);color:var(--fg)}
.find-results .h{display:block;font-weight:650;font-size:.95em}
.find-results .s{display:block;font-size:.87em;color:var(--muted);margin-top:3px}
.find-results mark{background:color-mix(in srgb,var(--accent) 30%,transparent);color:inherit;border-radius:3px}

/* pages ---------------------------------------------------------------- */
.page-head{padding:26px 0 6px}
h1{font-size:1.9rem;line-height:1.18;margin:.2em 0 .3em;letter-spacing:-.02em;font-weight:750}
.lead{color:var(--muted);font-size:1.04em;margin:.2em 0}
.meta{color:var(--muted);font-size:.88em}
.summary{margin-top:1em}
.crumbs{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:6px}
.crumbs a{font-size:12px;letter-spacing:.08em;text-transform:uppercase;font-weight:800;
  color:var(--accent2);border:none}
.empty{color:var(--muted)}

.group{margin:26px 0 30px}
.group-head{display:flex;align-items:baseline;gap:10px;border-bottom:1px solid var(--line);padding-bottom:6px}
.group-head h2{font-size:.8rem;letter-spacing:.15em;text-transform:uppercase;margin:0;font-weight:800}
.group-head h2 a{color:var(--accent2);border:none}
.group-head .n{font-size:12px;color:var(--muted)}
.group-desc{color:var(--muted);font-size:.92em;margin:.5em 0 0}

.cards{display:grid;gap:10px;margin-top:12px}
@media(min-width:720px){.cards{grid-template-columns:1fr 1fr}}
.card-book{
  display:block;background:var(--card);border:1px solid var(--line);border-radius:14px;
  padding:14px 15px 12px;box-shadow:var(--shadow);color:var(--fg);border-bottom:1px solid var(--line);
  position:relative;overflow:hidden;
}
.card-book:active{transform:scale(.995)}
.card-book .ct{display:block;font-weight:700;font-size:1.06em;line-height:1.3}
.card-book .cs{display:block;color:var(--muted);margin-top:3px;font-size:.95em}
.card-book .cd{display:block;margin-top:8px;font-size:.92em;line-height:1.5}
.card-book .cm{display:block;margin-top:10px;font-size:.82em;color:var(--muted)}
.card-book .tag{font-style:normal;background:var(--code);border-radius:5px;padding:1px 6px;margin-left:5px;font-size:.95em}
.card-book .cbar{position:absolute;left:0;bottom:0;height:2px;width:100%;background:transparent}
.card-book .cbar i{display:block;height:100%;width:0;background:var(--accent)}

.searchform{display:flex;gap:8px;margin-top:14px}
.searchform input{flex:1;font:inherit;font-size:16px;padding:11px 13px;border-radius:11px;
  border:1px solid var(--line);background:var(--card);color:var(--fg);min-width:0}
.searchform button{font:inherit;font-weight:650;padding:0 18px;border-radius:11px;
  border:1px solid var(--line);background:var(--card);color:var(--fg);cursor:pointer}

/* reader --------------------------------------------------------------- */
.book-head{padding-bottom:2px}
.toc-inline{background:var(--card);border:1px solid var(--line);border-radius:14px;
  padding:14px 16px;margin:22px 0;box-shadow:var(--shadow)}
.toc-inline h2{font-size:.8rem;text-transform:uppercase;letter-spacing:.1em;color:var(--muted);margin:.1em 0 .6em}
.toc-inline ol{margin:0;padding-left:1.15em}
.toc-inline > ol > li{margin:.4em 0;font-weight:600}
.toc-inline ol ol{padding-left:1em;margin:.22em 0 .5em}
.toc-inline ol ol li{font-weight:400;font-size:.94em;margin:.14em 0}
.toc-inline a{color:var(--fg);border-bottom:1px solid transparent}

.chapter{padding:28px 0 4px;border-top:1px solid var(--line);margin-top:24px}
.chapter:first-of-type{border-top:none}
#content h2{font-size:1.4rem;line-height:1.25;letter-spacing:-.015em;margin:.1em 0 .5em;font-weight:730}
#content h2 .anchor{opacity:0;margin-left:8px;font-size:.7em;border:none;color:var(--muted)}
#content h2:hover .anchor{opacity:1}
#content h4{font-size:1rem;margin:1.2em 0 .3em;font-weight:700;color:var(--muted)}
#content > p:first-child{margin-top:0}

details.card{border:1px solid var(--line);border-radius:12px;background:var(--card);
  margin:.75em 0;box-shadow:var(--shadow);overflow:hidden}
details.card > summary{cursor:pointer;list-style:none;padding:13px 44px 13px 15px;font-weight:650;
  position:relative;-webkit-tap-highlight-color:transparent}
details.card > summary::-webkit-details-marker{display:none}
details.card > summary::after{content:"";position:absolute;right:17px;top:50%;width:8px;height:8px;
  border-right:2px solid var(--muted);border-bottom:2px solid var(--muted);
  transform:translateY(-70%) rotate(45deg);transition:transform .18s ease}
details.card[open] > summary::after{transform:translateY(-30%) rotate(225deg)}
details.card[open] > summary{border-bottom:1px solid var(--line)}
.dbody{padding:2px 15px 12px}
.dbody > *:first-child{margin-top:.6em}

.fact,.warnbox,.tip{border-radius:12px;padding:13px 15px;margin:1.1em 0;border:1px solid var(--line);
  background:var(--card);box-shadow:var(--shadow)}
.fact{border-left:3px solid var(--accent2)}
.warnbox{border-left:3px solid var(--warn)}
.tip{border-left:3px solid var(--accent)}
.fact > p:first-of-type,.warnbox > p:first-of-type,.tip > p:first-of-type{margin-top:0}
.fact > p:last-child,.warnbox > p:last-child,.tip > p:last-child{margin-bottom:0}
.label{display:block;font-size:11.5px;letter-spacing:.1em;text-transform:uppercase;font-weight:800;margin-bottom:5px}
.fact .label{color:var(--accent2)}.warnbox .label{color:var(--warn)}.tip .label{color:var(--accent)}

.statgrid{display:grid;gap:10px;margin:1.1em 0}
@media(min-width:560px){.statgrid{grid-template-columns:1fr 1fr}}
.stat{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:12px 14px;box-shadow:var(--shadow)}
.stat .n{display:block;font-size:1.32rem;font-weight:750;letter-spacing:-.02em}
.stat .t{display:block;font-size:.85em;color:var(--muted);line-height:1.4;margin-top:3px}

.tw{overflow-x:auto;-webkit-overflow-scrolling:touch;margin:1em 0;border:1px solid var(--line);
  border-radius:12px;background:var(--card)}
table{border-collapse:collapse;width:100%;font-size:.92em;min-width:520px}
th,td{text-align:left;padding:9px 12px;border-bottom:1px solid var(--line);vertical-align:top}
th{font-weight:700;font-size:.84em;text-transform:uppercase;letter-spacing:.05em;color:var(--muted);white-space:nowrap}
tr:last-child td{border-bottom:none}
blockquote{margin:1em 0;padding:2px 0 2px 14px;border-left:3px solid var(--line);color:var(--muted)}

.doc-foot{margin-top:38px;padding-top:14px;border-top:1px solid var(--line);color:var(--muted);font-size:.85em}

/* desktop: keep the inline TOC as a side rail ---------------------------- */
@media(min-width:1100px){
  body.reader .wrap{max-width:62rem;padding-left:19rem}
  body.reader .toc-inline{position:fixed;left:max(18px,calc(50% - 31rem));top:70px;width:17rem;
    max-height:calc(100vh - 110px);overflow-y:auto;margin:0}
}

/* login ---------------------------------------------------------------- */
body.loginpage{display:grid;place-items:center;min-height:100vh;padding:20px}
.loginbox{width:100%;max-width:22rem;background:var(--card);border:1px solid var(--line);
  border-radius:16px;padding:24px 22px;box-shadow:var(--shadow)}
.loginbox h1{font-size:1.35rem;margin:0 0 .2em}
.loginbox form{display:grid;gap:12px;margin-top:18px}
.loginbox label{display:grid;gap:5px;font-size:.85em;color:var(--muted);font-weight:600}
.loginbox input{font:inherit;font-size:16px;padding:11px 12px;border-radius:10px;
  border:1px solid var(--line);background:var(--bg);color:var(--fg)}
.loginbox button{font:inherit;font-weight:700;padding:12px;border-radius:10px;border:1px solid var(--accent);
  background:var(--accent);color:#fff;cursor:pointer}
.loginbox button:disabled{opacity:.6}
.err{color:var(--warn);font-size:.9em;margin:0}

/* ==========================================================================
   Агент книги — чаты
   ========================================================================== */

.bar button .dot{display:inline-block;width:6px;height:6px;border-radius:50%;
  background:var(--accent2);margin-left:5px;vertical-align:middle}
.bar button .dot[hidden]{display:none}

.chat-head{align-items:center;gap:6px}
.chat-head .chat-title{flex:1;min-width:0;font-weight:650;font-size:15px;
  white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.chat-head .close{padding:0 13px;height:40px}
.chatbody{padding:14px 16px 20px}

/* --- список чатов --- */
.chat-intro{color:var(--muted);font-size:.92em;margin:0 0 14px}
.chat-new{display:block;width:100%;font:inherit;font-weight:650;padding:12px;
  border-radius:12px;border:1px dashed var(--line);background:var(--card);
  color:var(--accent);cursor:pointer;margin-bottom:16px}
.chat-list{display:grid;gap:8px}
.chat-item{display:block;width:100%;text-align:left;font:inherit;cursor:pointer;
  background:var(--card);border:1px solid var(--line);border-radius:12px;
  padding:11px 13px;color:var(--fg);box-shadow:var(--shadow)}
.chat-item .t{display:block;font-weight:600;line-height:1.35}
.chat-item .m{display:block;font-size:.8em;color:var(--muted);margin-top:4px}
.chat-item.closed{opacity:.72}
.chat-sec{font-size:11.5px;letter-spacing:.1em;text-transform:uppercase;
  font-weight:800;color:var(--muted);margin:18px 0 8px}

/* --- тред --- */
.msg{margin:0 0 16px}
.msg .who{font-size:11.5px;letter-spacing:.09em;text-transform:uppercase;
  font-weight:800;color:var(--muted);margin-bottom:5px}
.msg.user .bubble{background:var(--code);border-radius:12px;padding:11px 13px;
  white-space:pre-wrap;line-height:1.55}
.msg.agent .who{color:var(--accent)}
.msg.agent .bubble > *:first-child{margin-top:0}
.msg.agent .bubble > *:last-child{margin-bottom:0}
.msg.agent .bubble h1,.msg.agent .bubble h2,.msg.agent .bubble h3{font-size:1.05rem;margin:1em 0 .3em}
.msg.agent .bubble table{min-width:0}
.msg.agent .bubble pre{font-size:.85em}
.msg .err{color:var(--warn);background:var(--card);border:1px solid var(--warn);
  border-radius:10px;padding:10px 12px;font-size:.92em}

.trace{border:1px solid var(--line);border-radius:10px;background:var(--card);
  margin:10px 0 0;overflow:hidden}
.trace > summary{cursor:pointer;list-style:none;padding:8px 12px;font-size:.84em;
  color:var(--muted);font-weight:600;-webkit-tap-highlight-color:transparent}
.trace > summary::-webkit-details-marker{display:none}
.trace[open] > summary{border-bottom:1px solid var(--line)}
.trace ol{margin:0;padding:8px 12px 10px 26px;font-size:.84em;color:var(--muted)}
.trace li{margin:.3em 0;line-height:1.45}
.trace .k{color:var(--fg);font-weight:600}
.trace .bad{color:var(--warn)}
.msg .meta{font-size:.76em;color:var(--muted);margin-top:6px}

.working{display:flex;align-items:center;gap:9px;color:var(--muted);font-size:.9em}
.working .sp{width:13px;height:13px;border:2px solid var(--line);
  border-top-color:var(--accent);border-radius:50%;animation:spin .8s linear infinite;flex:0 0 auto}
@keyframes spin{to{transform:rotate(360deg)}}

/* --- ввод --- */
.composer{border-top:1px solid var(--line);background:var(--bar);
  backdrop-filter:blur(12px);padding:10px 14px calc(10px + env(safe-area-inset-bottom));
  display:grid;grid-template-columns:1fr auto;gap:8px;align-items:end}
.composer[hidden]{display:none}
.composer .quoted{grid-column:1/-1;background:var(--card);border:1px solid var(--line);
  border-left:3px solid var(--accent2);border-radius:10px;padding:8px 11px;
  font-size:.85em;color:var(--muted);max-height:8em;overflow:auto}
.composer .quoted b{display:block;color:var(--accent2);font-size:.85em;
  letter-spacing:.08em;text-transform:uppercase;margin-bottom:3px}
.composer textarea{font:inherit;font-size:16px;line-height:1.45;padding:10px 12px;
  border-radius:12px;border:1px solid var(--line);background:var(--card);color:var(--fg);
  resize:none;max-height:9em;min-width:0}
.composer button{font:inherit;font-weight:700;font-size:17px;width:44px;height:44px;
  border-radius:12px;border:1px solid var(--accent);background:var(--accent);
  color:#fff;cursor:pointer}
.composer button:disabled{opacity:.45;cursor:default}

/* --- всплывашка на выделении --- */
#selAsk{position:absolute;z-index:55;transform:translate(-50%,-100%)}
#selAsk[hidden]{display:none}
#selAsk button{font:inherit;font-size:13.5px;font-weight:650;white-space:nowrap;
  padding:8px 13px;border-radius:10px;border:1px solid var(--line);
  background:var(--card);color:var(--fg);cursor:pointer;
  box-shadow:0 4px 16px rgba(0,0,0,.18)}

.chat-empty{color:var(--muted);text-align:center;padding:30px 10px}

/* Узкий телефон: пять кнопок с подписями не помещаются в строку — оставляем
   иконки. Ярлык скрыт только визуально, aria-label остаётся для доступности. */
@media (max-width: 500px){
  .bar .lbl{display:none}
  .bar button,.bar .btn{padding:9px 14px;font-size:16px}
}