:root{--bg: #eef2f9;--bg-tint: #e6edf8;--surface: #ffffff;--surface-2: #f1f5fc;--sidebar: #e5ecf8;--sidebar-2: #d8e2f3;--ink: #11243f;--ink-soft: #3a4a64;--muted: #6b7c97;--line: #d9e2f1;--line-soft: #e7edf7;--brand: #137fec;--brand-strong: #0c63bd;--brand-soft: #e3eefc;--on-brand: #ffffff;--ai-bubble: #e9f1fd;--ai-border: #d3e3fb;--ok: #15966b;--warn: #a8670f;--danger: #d6453f;--shadow: 0 14px 40px rgba(17, 36, 63, .09);--glow: radial-gradient( 820px 420px at 78% -10%, rgba(19, 127, 236, .16), transparent 60% ), radial-gradient(620px 360px at 8% 8%, rgba(19, 127, 236, .08), transparent 55%)}[data-theme=dark]{--bg: #0a1421;--bg-tint: #0c1828;--surface: #111f33;--surface-2: #16243a;--sidebar: #0b1626;--sidebar-2: #17273f;--ink: #e7eef9;--ink-soft: #b7c4d8;--muted: #8497b2;--line: #20304a;--line-soft: #1a2840;--brand: #3d9bf6;--brand-strong: #62aef8;--brand-soft: #16304e;--on-brand: #ffffff;--ai-bubble: #14243c;--ai-border: #213650;--ok: #3cc28d;--warn: #e0a44a;--danger: #f0726c;--shadow: 0 18px 50px rgba(0, 0, 0, .45);--glow: radial-gradient( 820px 420px at 78% -10%, rgba(61, 155, 246, .16), transparent 60% ), radial-gradient(620px 360px at 8% 8%, rgba(61, 155, 246, .08), transparent 55%)}*{box-sizing:border-box}html,body,#root{height:100%;margin:0}body{font-family:Manrope,system-ui,-apple-system,sans-serif;color:var(--ink);background:var(--bg);-webkit-font-smoothing:antialiased}[data-theme=dark] .side-brand img,[data-theme=dark] .landing-brand img,[data-theme=dark] .auth-logo,[data-theme=dark] .splash img{filter:brightness(0) invert(1)}.spin{animation:spin .9s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}@keyframes rise{0%{opacity:0;transform:translateY(16px)}to{opacity:1;transform:none}}.history-list::-webkit-scrollbar,.stream::-webkit-scrollbar{width:8px}.history-list::-webkit-scrollbar-thumb,.stream::-webkit-scrollbar-thumb{background:var(--line);border-radius:99px}.splash{height:100dvh;display:grid;place-items:center;background:var(--bg)}.splash img{width:110px;opacity:.9;animation:rise .6s both}.landing-glow{position:fixed;inset:0;background:var(--glow);pointer-events:none;z-index:0}.landing{position:relative;min-height:100dvh;display:flex;flex-direction:column;z-index:1}.landing>*{position:relative;z-index:1}.landing-nav{display:flex;align-items:center;justify-content:space-between;padding:22px clamp(20px,5vw,64px);max-width:1180px;margin:0 auto;width:100%}.landing-brand{display:flex;align-items:center;gap:10px;font-family:"Instrument Serif",serif;font-size:24px;color:var(--ink)}.landing-brand img{height:30px}.landing-nav-actions{display:flex;align-items:center;gap:10px}.link-btn{background:none;border:none;font:inherit;font-weight:600;font-size:14px;color:var(--ink-soft);cursor:pointer;padding:8px 10px;display:inline-flex;align-items:center;gap:6px}.link-btn:hover{color:var(--brand)}.cta-sm{font:inherit;font-weight:700;font-size:14px;color:var(--on-brand);background:var(--brand);border:none;border-radius:10px;padding:9px 16px;cursor:pointer}.cta-sm:hover{background:var(--brand-strong)}.landing-hero{flex:1;display:flex;flex-direction:column;align-items:center;text-align:center;justify-content:center;padding:clamp(40px,8vh,96px) 24px 40px;max-width:860px;margin:0 auto}.eyebrow{font-size:13px;font-weight:700;letter-spacing:.12em;text-transform:uppercase;color:var(--brand);background:var(--brand-soft);padding:7px 14px;border-radius:999px;animation:rise .7s both;animation-delay:.05s}.landing-hero h1{font-family:"Instrument Serif",serif;font-weight:400;font-size:clamp(40px,7vw,72px);line-height:1.04;letter-spacing:-.01em;margin:22px 0 0;color:var(--ink);animation:rise .7s both;animation-delay:.12s}.landing-hero h1 em{font-style:italic;color:var(--brand)}.landing-hero .lead{font-size:clamp(16px,2.2vw,19px);line-height:1.6;color:var(--ink-soft);max-width:60ch;margin:22px 0 0;animation:rise .7s both;animation-delay:.22s}.hero-cta{display:flex;flex-wrap:wrap;gap:12px;justify-content:center;margin-top:32px;animation:rise .7s both;animation-delay:.32s}.cta{display:inline-flex;align-items:center;gap:9px;font:inherit;font-weight:700;font-size:16px;color:var(--on-brand);background:var(--brand);border:none;border-radius:13px;padding:14px 24px;cursor:pointer;box-shadow:0 10px 26px #137fec52;transition:transform .15s ease,background .15s ease}.cta:hover{background:var(--brand-strong);transform:translateY(-1px)}.cta-ghost{font:inherit;font-weight:600;font-size:16px;color:var(--ink);background:var(--surface);border:1px solid var(--line);border-radius:13px;padding:14px 22px;cursor:pointer}.cta-ghost:hover{border-color:var(--brand);color:var(--brand)}.trust{margin-top:26px;font-size:13.5px;color:var(--muted);animation:rise .7s both;animation-delay:.42s}.landing-features{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;max-width:1040px;margin:0 auto;padding:20px clamp(20px,5vw,64px) 40px;width:100%}.feat{background:var(--surface);border:1px solid var(--line);border-radius:18px;padding:26px 24px;box-shadow:var(--shadow);animation:rise .7s both;transition:transform .18s ease}.feat:hover{transform:translateY(-3px)}.feat-icon{width:46px;height:46px;border-radius:13px;display:grid;place-items:center;color:var(--brand);background:var(--brand-soft);margin-bottom:16px}.feat h3{font-size:18px;margin:0 0 8px;color:var(--ink)}.feat p{font-size:14.5px;line-height:1.6;color:var(--ink-soft);margin:0}.landing-foot{text-align:center;font-size:12px;color:var(--muted);padding:18px 24px 28px}.auth-wrap{position:relative;min-height:100dvh;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:14px;padding:24px}.auth-top{position:absolute;top:20px;left:0;right:0;display:flex;align-items:center;justify-content:space-between;padding:0 clamp(20px,5vw,48px);z-index:2}.auth-top .back{color:var(--ink-soft)}.auth-card{position:relative;z-index:1;width:100%;max-width:384px;background:var(--surface);border:1px solid var(--line);border-radius:20px;padding:34px 30px;text-align:center;box-shadow:var(--shadow)}.auth-logo{width:84px;margin-bottom:8px}.auth-card h1{font-family:"Instrument Serif",serif;font-weight:400;font-size:31px;margin:0;color:var(--ink)}.auth-sub{color:var(--muted);font-size:14px;margin:6px 0 20px}.auth-form{display:flex;flex-direction:column;gap:10px}.auth-form input{font:inherit;font-size:15px;padding:12px 14px;border:1px solid var(--line);border-radius:11px;outline:none;background:var(--surface-2);color:var(--ink)}.auth-form input:focus{border-color:var(--brand)}.auth-error{color:var(--danger);font-size:13px;text-align:left}.auth-toggle{font-size:14px;color:var(--muted);margin:16px 0 0}.auth-toggle button{background:none;border:none;color:var(--brand);font:inherit;font-weight:600;cursor:pointer}.theme-toggle{width:38px;height:38px;display:inline-grid;place-items:center;border-radius:10px;border:1px solid var(--line);background:var(--surface);color:var(--ink-soft);cursor:pointer}.theme-toggle:hover{color:var(--brand);border-color:var(--brand)}.side-user .theme-toggle{width:30px;height:30px;border:none;background:none;color:var(--muted)}.side-user .theme-toggle:hover{color:var(--brand)}.app{height:100dvh;display:flex}.sidebar{width:268px;flex:none;background:var(--sidebar);color:var(--ink);display:flex;flex-direction:column;padding:16px 12px;gap:14px;border-right:1px solid var(--line)}.side-brand{display:flex;align-items:center;gap:9px;padding:2px 6px}.side-brand img{height:28px}.side-tabs{display:flex;flex-direction:column;gap:4px}.side-tab{display:flex;align-items:center;gap:10px;font:inherit;font-size:14px;font-weight:600;color:var(--ink-soft);background:none;border:none;text-align:left;padding:10px 12px;border-radius:10px;cursor:pointer}.side-tab:hover{background:var(--sidebar-2)}.side-tab.active{background:var(--brand);color:var(--on-brand)}.history{flex:1;min-height:0;display:flex;flex-direction:column;gap:8px}.new-chat{display:flex;align-items:center;justify-content:center;gap:7px;font:inherit;font-size:13px;font-weight:600;color:var(--ink);background:var(--surface);border:1px solid var(--line);border-radius:10px;padding:9px;cursor:pointer}.new-chat:hover{border-color:var(--brand);color:var(--brand)}.history-list{flex:1;min-height:0;overflow-y:auto;display:flex;flex-direction:column;gap:2px}.history-empty{font-size:12.5px;color:var(--muted);padding:8px 6px}.history-item{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--ink-soft);padding:9px 10px;border-radius:8px;cursor:pointer}.history-item:hover{background:var(--sidebar-2)}.history-item.active{background:var(--brand-soft);color:var(--brand-strong)}.hi-title{flex:1;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.hi-del{opacity:0;color:var(--muted);display:inline-flex}.history-item:hover .hi-del{opacity:1}.hi-del:hover{color:var(--danger)}.side-user{display:flex;align-items:center;gap:8px;padding-top:12px;border-top:1px solid var(--line)}.avatar{width:30px;height:30px;border-radius:50%;background:var(--brand);color:var(--on-brand);display:grid;place-items:center;font-weight:700;font-size:14px;flex:none}.side-name{flex:1;font-size:13px;font-weight:600;color:var(--ink);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.logout{background:none;border:none;color:var(--muted);cursor:pointer;display:inline-flex;padding:4px}.logout:hover{color:var(--danger)}.scrim{display:none}.main{flex:1;min-width:0;display:flex;flex-direction:column;background:var(--bg)}.topbar{flex:none;display:none;align-items:center;gap:12px;padding:12px 16px;background:var(--surface);border-bottom:1px solid var(--line)}.hamburger{background:none;border:none;cursor:pointer;color:var(--ink);display:inline-flex}.topbar-title{font-weight:700;color:var(--ink)}.content{flex:1;min-height:0;display:flex}.pane{display:none;flex:1;min-height:0}.pane.show{display:flex}.feature{flex:1;display:flex;flex-direction:column;min-height:0}.poc-banner{flex:none;display:flex;flex-wrap:wrap;align-items:center;gap:6px 10px;font-size:12.5px;line-height:1.4;color:var(--ink-soft);background:var(--brand-soft);border-bottom:1px solid var(--line);padding:9px 18px}.poc-banner>svg{color:var(--brand);flex:none}.poc-banner strong{color:var(--ink)}.poc-books{display:inline-flex;flex-wrap:wrap;gap:6px}.poc-book{font-weight:600;font-size:12px;color:var(--muted);background:var(--surface);border:1px solid var(--line);border-radius:999px;padding:2px 9px}.poc-book.ready{color:var(--brand-strong);border-color:var(--brand)}.poc-book em{font-style:normal;font-weight:500;color:var(--muted)}.stream{flex:1;overflow-y:auto;padding:24px;display:flex;flex-direction:column;gap:18px;max-width:860px;width:100%;margin:0 auto}.empty,.case-intro{margin:auto;max-width:560px;text-align:center;padding:24px}.empty h2,.case-intro h2{font-family:"Instrument Serif",serif;font-weight:400;font-size:32px;margin:0 0 8px;color:var(--ink)}.empty p,.case-intro p{color:var(--muted);margin:0 0 18px;line-height:1.55}.chips{display:flex;flex-wrap:wrap;gap:8px;justify-content:center}.chip{font:inherit;font-size:13px;color:var(--ink-soft);background:var(--surface);border:1px solid var(--line);padding:8px 12px;border-radius:999px;cursor:pointer}.chip:hover{border-color:var(--brand);color:var(--brand)}.case-start{display:flex;gap:8px;margin-bottom:16px}.case-start input{flex:1;font:inherit;font-size:15px;padding:12px 14px;border:1px solid var(--line);border-radius:12px;outline:none;background:var(--surface);color:var(--ink)}.case-start input:focus{border-color:var(--brand)}.qa{display:flex;flex-direction:column;gap:10px}.q{align-self:flex-end;max-width:85%;background:var(--brand);color:var(--on-brand);padding:10px 14px;border-radius:14px 14px 4px;font-size:15px;line-height:1.5}.q-label{display:block;font-size:11px;text-transform:uppercase;letter-spacing:.05em;opacity:.75;margin-bottom:2px}.q-img{display:block;max-width:220px;max-height:180px;border-radius:10px;margin-bottom:6px}.a{align-self:flex-start;max-width:92%;background:var(--surface);border:1px solid var(--line);border-radius:14px 14px 14px 4px;padding:14px 16px;color:var(--ink)}.a-head{display:flex;align-items:center;gap:10px;margin-bottom:6px}.a-label{font-size:11px;text-transform:uppercase;letter-spacing:.05em;color:var(--muted);font-weight:700}.badge{display:inline-flex;align-items:center;gap:4px;font-size:11px;font-weight:600;padding:3px 8px;border-radius:999px}.badge.grounded{color:var(--ok);background:color-mix(in srgb,var(--ok) 14%,transparent)}.badge.ungrounded{color:var(--warn);background:color-mix(in srgb,var(--warn) 16%,transparent)}.speak-btn{margin-left:auto;background:none;border:1px solid var(--line);border-radius:8px;width:26px;height:26px;display:inline-grid;place-items:center;color:var(--muted);cursor:pointer}.speak-btn:hover{color:var(--brand);border-color:var(--brand)}.a.loading,.a.error{color:var(--muted);font-size:14px;display:flex;align-items:center;gap:8px}.a.error{color:var(--danger)}.sources{margin-top:12px;border-top:1px dashed var(--line);padding-top:10px}.sources summary{cursor:pointer;font-size:13px;font-weight:600;color:var(--brand-strong);display:flex;align-items:center;gap:6px}.sources ol{margin:10px 0 0;padding-left:18px;display:flex;flex-direction:column;gap:10px}.src-head{display:flex;flex-wrap:wrap;align-items:baseline;gap:8px;font-size:13px;color:var(--ink)}.src-head .page{color:var(--brand-strong);font-weight:600}.src-head .sim{color:var(--muted);font-size:11px}.src-snippet{margin:4px 0 0;font-size:12.5px;color:var(--muted);line-height:1.5}.src.clickable{cursor:pointer;border-radius:8px;margin:0 -8px;padding:6px 8px;transition:background .12s ease}.src.clickable:hover{background:var(--brand-soft)}.src-view{display:inline-flex;align-items:center;gap:3px;font-size:11px;font-weight:600;color:var(--brand);margin-left:auto}.pdf-modal{position:fixed;inset:0;z-index:60;background:#080f1c8c;display:flex;align-items:center;justify-content:center;padding:20px}.pdf-panel{background:var(--surface);border:1px solid var(--line);border-radius:16px;width:min(840px,100%);max-height:92vh;display:flex;flex-direction:column;overflow:hidden;box-shadow:var(--shadow)}.pdf-head{flex:none;display:flex;align-items:center;justify-content:space-between;padding:14px 18px;border-bottom:1px solid var(--line)}.pdf-title{display:flex;align-items:baseline;gap:10px;font-size:14px;color:var(--ink)}.pdf-title span{color:var(--brand-strong);font-weight:600;font-size:13px}.pdf-close{background:none;border:none;cursor:pointer;color:var(--muted);display:inline-flex}.pdf-close:hover{color:var(--ink)}.pdf-body{flex:1;min-height:0;overflow:auto;padding:16px;display:flex;justify-content:center;background:var(--bg)}.pdf-status{display:flex;align-items:center;gap:8px;color:var(--muted);font-size:14px;padding:48px 20px}.pdf-status.error{color:var(--danger)}.pdf-canvas-wrap{position:relative}.pdf-canvas-wrap canvas{display:block;border:1px solid var(--line);box-shadow:0 4px 18px #0000001f}.pdf-hl{position:absolute;background:#facc1552;outline:1.5px solid rgba(234,179,8,.7);border-radius:2px;pointer-events:none}.stream.case{gap:12px}.bubble{max-width:85%;padding:11px 14px;border-radius:14px;font-size:15px;line-height:1.55;position:relative}.bubble.ai{align-self:flex-start;background:var(--ai-bubble);border:1px solid var(--ai-border);border-bottom-left-radius:4px;color:var(--ink);padding-bottom:30px}.bubble.ai .speak-btn{position:absolute;bottom:6px;left:12px;background:transparent}.bubble.student{align-self:flex-end;background:var(--brand);color:var(--on-brand);border-bottom-right-radius:4px}.case-actions{flex:none;display:flex;flex-wrap:wrap;gap:8px;padding:10px 16px 0;max-width:860px;width:100%;margin:0 auto}.ghost{font:inherit;font-size:13px;font-weight:600;display:inline-flex;align-items:center;gap:6px;color:var(--brand-strong);background:var(--brand-soft);border:1px solid transparent;padding:8px 12px;border-radius:999px;cursor:pointer}.ghost:hover:not(:disabled){border-color:var(--brand)}.ghost:disabled{opacity:.45;cursor:not-allowed}.composer{flex:none;padding:14px 16px;max-width:860px;width:100%;margin:0 auto}.composer-row{display:flex;align-items:center;gap:6px}.mic-error{font-size:12.5px;color:var(--danger);margin-bottom:8px}.composer input{flex:1;font:inherit;font-size:15px;padding:12px 14px;border:1px solid var(--line);border-radius:12px;background:var(--surface);color:var(--ink);outline:none}.composer input:focus{border-color:var(--brand)}.icon-btn{flex:none;width:42px;height:44px;display:inline-grid;place-items:center;background:var(--surface);border:1px solid var(--line);border-radius:12px;color:var(--muted);cursor:pointer}.icon-btn:hover:not(:disabled){color:var(--brand);border-color:var(--brand)}.icon-btn.rec{color:#fff;background:var(--danger);border-color:var(--danger);animation:pulse 1.2s infinite}@keyframes pulse{0%,to{opacity:1}50%{opacity:.6}}.composer .send{flex:none;width:46px;height:44px;display:inline-grid;place-items:center;background:var(--brand);color:var(--on-brand);border:none;border-radius:12px;cursor:pointer}.composer .send:disabled,.icon-btn:disabled{opacity:.45;cursor:not-allowed}.attach-preview{position:relative;width:72px;margin-bottom:8px}.attach-preview img{width:72px;height:72px;object-fit:cover;border-radius:10px;border:1px solid var(--line)}.attach-preview button{position:absolute;top:-7px;right:-7px;width:20px;height:20px;border-radius:50%;background:var(--ink);color:var(--bg);border:none;display:grid;place-items:center;cursor:pointer}.primary{display:inline-flex;align-items:center;justify-content:center;gap:6px;font:inherit;font-weight:600;background:var(--brand);color:var(--on-brand);border:none;border-radius:12px;padding:0 18px;min-height:44px;cursor:pointer}.primary:hover:not(:disabled){background:var(--brand-strong)}.primary:disabled{opacity:.5;cursor:not-allowed}.case-intro .start-case{margin:6px auto 0;padding:0 26px;min-height:48px;font-size:15px}.start-error{color:var(--danger);font-size:13px;margin-top:12px}.md>:first-child{margin-top:0}.md>:last-child{margin-bottom:0}.md p{margin:0 0 10px;line-height:1.6}.md ul,.md ol{margin:0 0 10px;padding-left:20px}.md li{margin:3px 0;line-height:1.55}.md strong{font-weight:700}.md h1,.md h2,.md h3{font-size:16px;margin:12px 0 6px}.md hr{border:none;border-top:1px solid var(--line);margin:12px 0}.md code{background:var(--surface-2);padding:1px 5px;border-radius:5px;font-size:.9em}.dots{display:inline-flex;gap:4px}.dots i{width:6px;height:6px;border-radius:50%;background:var(--brand);animation:blink 1.2s infinite ease-in-out both}.dots i:nth-child(2){animation-delay:.2s}.dots i:nth-child(3){animation-delay:.4s}@keyframes blink{0%,80%,to{opacity:.25}40%{opacity:1}}.disclaimer{flex:none;font-size:11px;color:var(--muted);text-align:center;padding:8px 16px;background:var(--surface);border-top:1px solid var(--line)}@media(max-width:860px){.landing-features{grid-template-columns:1fr}}@media(max-width:820px){.topbar{display:flex}.sidebar{position:fixed;inset:0 auto 0 0;z-index:40;transform:translate(-100%);transition:transform .2s ease;box-shadow:0 0 40px #0000004d}.sidebar.open{transform:translate(0)}.scrim{display:block;position:fixed;inset:0;background:#080f1c80;z-index:30}.stream{padding:14px}.q,.a,.bubble{max-width:100%}.case-start{flex-direction:column}.composer{padding:10px 12px}}