/* এআই সহায়ক — floating course chat (assets/guru.js). Uses the site tokens from style.css; --gu = persona colour.
   No letter-spacing anywhere (breaks Bangla conjuncts). */
.gu-root{--gu:#0050ed;position:fixed;right:20px;bottom:20px;z-index:900;font-family:var(--sans,system-ui);display:flex;flex-direction:column;align-items:flex-end;gap:12px}
.gu-root svg{width:18px;height:18px;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round;display:block}
.gu-root.gu-learn{bottom:24px}

/* launcher */
.gu-fab{display:flex;align-items:center;gap:10px;padding:6px 16px 6px 6px;border-radius:999px;border:1px solid color-mix(in srgb,var(--gu) 35%,var(--line,#e4e8f1));background:var(--card,#fff);color:var(--ink,#0b1430);cursor:pointer;box-shadow:0 10px 30px color-mix(in srgb,var(--gu) 28%,transparent),0 2px 6px rgba(16,24,64,.08);transition:transform .2s,box-shadow .2s;text-align:left}
.gu-fab:hover{transform:translateY(-2px);box-shadow:0 14px 36px color-mix(in srgb,var(--gu) 36%,transparent)}
.gu-fab:focus-visible,.gu-ib:focus-visible,.gu-send:focus-visible,.gu-chip:focus-visible{outline:3px solid color-mix(in srgb,var(--gu) 55%,transparent);outline-offset:2px}
.gu-fab-av{position:relative;width:46px;height:46px;border-radius:50%;flex:none;background:linear-gradient(135deg,var(--gu),color-mix(in srgb,var(--gu) 55%,#38d3f5));box-shadow:0 0 0 3px color-mix(in srgb,var(--gu) 22%,transparent)}
.gu-fab-av img{width:100%;height:100%;border-radius:50%;object-fit:cover}
.gu-fab-av i{position:absolute;right:-3px;bottom:-3px;width:20px;height:20px;border-radius:50%;background:var(--gu);color:#fff;display:grid;place-items:center;border:2px solid var(--card,#fff)}
.gu-fab-av i svg{width:11px;height:11px;fill:#fff;stroke:none}
.gu-fab-av::after{content:"";position:absolute;inset:-4px;border-radius:50%;border:2px solid var(--gu);opacity:0;animation:gu-ping 2.8s ease-out 1.2s 3}
@keyframes gu-ping{0%{opacity:.7;transform:scale(.9)}100%{opacity:0;transform:scale(1.35)}}
.gu-fab-t{display:flex;flex-direction:column;line-height:1.25}
.gu-fab-t b{font-size:15px;font-weight:700}
.gu-fab-t small{font-size:12px;color:var(--mut,#5b6382)}
.gu-open .gu-fab{display:none}

/* panel */
.gu-panel{width:400px;height:min(640px,calc(100vh - 40px));display:flex;flex-direction:column;background:var(--bg,#fff);border:1px solid var(--line,#e4e8f1);border-radius:20px;box-shadow:var(--shadow-lg,0 30px 70px rgba(16,24,64,.14));overflow:hidden;animation:gu-in .22s ease-out}
.gu-panel[hidden]{display:none}
@keyframes gu-in{from{opacity:0;transform:translateY(12px) scale(.98)}to{opacity:1;transform:none}}
.gu-top{display:flex;align-items:center;gap:10px;padding:12px 12px 12px 14px;color:#fff;background:linear-gradient(120deg,color-mix(in srgb,var(--gu) 88%,#011835),color-mix(in srgb,var(--gu) 70%,#38d3f5))}
.gu-av{width:42px;height:42px;border-radius:50%;flex:none;background:rgba(255,255,255,.25);border:2px solid rgba(255,255,255,.7);overflow:hidden}
.gu-av img{width:100%;height:100%;object-fit:cover}
.gu-who{flex:1;min-width:0;display:flex;flex-direction:column;line-height:1.3}
.gu-who b{font-size:16px}
.gu-who span{font-size:12px;opacity:.92;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.gu-badge{font-style:normal;font-weight:700;font-size:11px;background:rgba(255,255,255,.22);border:1px solid rgba(255,255,255,.45);border-radius:999px;padding:0 7px;margin-right:6px}
.gu-ib{width:36px;height:36px;border-radius:10px;border:0;background:transparent;color:inherit;display:grid;place-items:center;cursor:pointer;flex:none}
.gu-top .gu-ib:hover{background:rgba(255,255,255,.18)}

.gu-log{flex:1;overflow-y:auto;padding:16px 14px 8px;display:flex;flex-direction:column;gap:12px;background:var(--soft,#f5f7fb);overscroll-behavior:contain}
.gu-msg{display:flex;gap:8px;align-items:flex-end;max-width:100%}
.gu-me{justify-content:flex-end}
.gu-mav{width:28px;height:28px;border-radius:50%;flex:none;overflow:hidden;background:color-mix(in srgb,var(--gu) 30%,var(--soft2,#eef1f8))}
.gu-mav img{width:100%;height:100%;object-fit:cover}
.gu-bub{max-width:86%;padding:10px 13px;border-radius:16px;font-size:15px;line-height:1.65;color:var(--txt,#1c2440);overflow-wrap:anywhere}
.gu-bot .gu-bub{background:var(--card,#fff);border:1px solid var(--line,#e4e8f1);border-bottom-left-radius:6px}
.gu-me .gu-bub{background:var(--gu);color:#fff;border-bottom-right-radius:6px}
.gu-err .gu-bub{background:color-mix(in srgb,var(--red,#d63c3c) 10%,var(--card,#fff));border-color:color-mix(in srgb,var(--red,#d63c3c) 35%,transparent)}
.gu-bub p{margin:0 0 .5em}.gu-bub p:last-child{margin-bottom:0}
.gu-bub .gu-h{font-weight:700;color:var(--ink,#0b1430)}
.gu-bub ul,.gu-bub ol{margin:.2em 0 .6em;padding-left:1.3em}
.gu-bub li{margin:.15em 0}
.gu-bub a{color:var(--gu);text-decoration:underline}
.gu-bub code{font-family:ui-monospace,Consolas,monospace;font-size:.88em;background:color-mix(in srgb,var(--gu) 10%,transparent);padding:.05em .35em;border-radius:5px}
.gu-me .gu-bub code{background:rgba(255,255,255,.2)}
.gu-code{margin:.4em 0 .7em;border-radius:10px;overflow:hidden;border:1px solid #1e2745;background:#0b1226}
.gu-code-h{display:flex;align-items:center;justify-content:space-between;padding:4px 6px 4px 12px;background:#141d38;color:#98a0bf;font-size:12px;font-family:ui-monospace,Consolas,monospace}
.gu-copy{display:inline-flex;align-items:center;gap:5px;border:0;background:transparent;color:#d9deee;font-size:12px;padding:4px 8px;border-radius:6px;cursor:pointer}
.gu-copy:hover{background:#1f2a4d}.gu-copy.ok{color:#3ddc97}
.gu-copy svg{width:14px;height:14px}
.gu-code pre{margin:0;padding:10px 12px;overflow-x:auto;color:#e8ecff;font-size:13.5px;line-height:1.55}
.gu-code pre code{background:none;padding:0;font-size:inherit;color:inherit}
.gu-tbl{overflow-x:auto;margin:.4em 0 .7em}
.gu-tbl table{border-collapse:collapse;font-size:13.5px;min-width:100%}
.gu-tbl th,.gu-tbl td{border:1px solid var(--line,#e4e8f1);padding:5px 8px;text-align:left;vertical-align:top}
.gu-tbl th{background:var(--soft2,#eef1f8)}
.gu-uimg{display:block;max-width:220px;max-height:180px;border-radius:10px;margin-bottom:6px;object-fit:cover}
.gu-src{display:flex;flex-wrap:wrap;gap:6px;margin-top:8px;padding-top:8px;border-top:1px dashed var(--line2,#d6dbe8)}
.gu-src a{display:inline-flex;align-items:center;gap:5px;font-size:12.5px;text-decoration:none;color:var(--gu);background:color-mix(in srgb,var(--gu) 9%,transparent);border-radius:999px;padding:3px 10px 3px 8px;max-width:100%}
.gu-src a span{white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.gu-src svg{width:13px;height:13px;flex:none}
.gu-login{margin-top:10px;display:flex;flex-wrap:wrap;gap:8px;align-items:center}
.gu-login p{width:100%;margin:0 0 2px;font-size:14px;color:var(--mut,#5b6382)}
.gu-chips{display:flex;flex-direction:column;align-items:flex-start;gap:7px;padding-left:36px}
.gu-chip{border:1px solid color-mix(in srgb,var(--gu) 40%,var(--line,#e4e8f1));background:var(--card,#fff);color:var(--gu);font-size:14px;padding:7px 12px;border-radius:14px;cursor:pointer;text-align:left;line-height:1.4}
.gu-chip:hover{background:color-mix(in srgb,var(--gu) 8%,var(--card,#fff))}
.gu-dots{display:inline-flex;gap:4px;padding:4px 0}
.gu-dots i{width:7px;height:7px;border-radius:50%;background:var(--gu);opacity:.35;animation:gu-dot 1s infinite}
.gu-dots i:nth-child(2){animation-delay:.15s}.gu-dots i:nth-child(3){animation-delay:.3s}
@keyframes gu-dot{50%{opacity:1;transform:translateY(-3px)}}
.gu-caret{display:inline-block;width:7px;height:1em;vertical-align:-2px;background:var(--gu);margin-left:2px;animation:gu-blink 1s steps(2) infinite}
@keyframes gu-blink{50%{opacity:0}}

.gu-foot{border-top:1px solid var(--line,#e4e8f1);background:var(--bg,#fff);padding:8px 10px calc(8px + env(safe-area-inset-bottom))}
.gu-prev{display:flex;align-items:center;gap:10px;padding:6px;margin-bottom:6px;border:1px dashed var(--line2,#d6dbe8);border-radius:12px;font-size:13px;color:var(--mut,#5b6382)}
.gu-prev[hidden]{display:none}
.gu-prev img{width:48px;height:48px;border-radius:8px;object-fit:cover}
.gu-prev span{flex:1}
.gu-form{display:flex;align-items:flex-end;gap:6px}
.gu-form[hidden]{display:none}
.gu-attach{color:var(--mut,#5b6382)}
.gu-attach:hover{background:var(--soft,#f5f7fb);color:var(--gu)}
.gu-form textarea{flex:1;font-family:inherit;resize:none;border:1px solid var(--line2,#d6dbe8);border-radius:14px;padding:8px 12px;font-size:16px;line-height:1.45;max-height:140px;overflow-y:auto;scrollbar-width:thin;background:var(--card,#fff);color:var(--ink,#0b1430);outline:none}
.gu-form textarea:focus{border-color:var(--gu);box-shadow:0 0 0 3px color-mix(in srgb,var(--gu) 18%,transparent)}
.gu-send{width:40px;height:40px;border-radius:12px;border:0;background:var(--gu);color:#fff;display:grid;place-items:center;cursor:pointer;flex:none}
.gu-form.busy .gu-send{opacity:.5;cursor:wait}
.gu-note{margin:6px 2px 0;font-size:11.5px;color:var(--faint,#8b92ad);line-height:1.45}
.gu-left{color:var(--mut,#5b6382);font-weight:600}

@media (max-width:640px){
  .gu-root{right:12px;bottom:12px}
  .gu-root.gu-learn{bottom:84px} /* above learn.css mobile prev/next bar */
  .gu-fab{padding:5px}
  .gu-fab-t{display:none}
  .gu-fab-av{width:52px;height:52px}
  .gu-root.gu-open{inset:0;right:0;bottom:0}
  .gu-panel{width:100vw;height:100dvh;border-radius:0;border:0}
  html.gu-lock,html.gu-lock body{overflow:hidden}
}
@media (prefers-reduced-motion:reduce){.gu-panel,.gu-fab-av::after,.gu-dots i,.gu-caret{animation:none}}
@media print{.gu-root{display:none}}