/* ── Reset & Tokens ─────────────────────────────────────── */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
:root{
  --bg:#13131f;--bg2:#1a1a2e;
  --surface:rgba(255,255,255,0.04);--surface2:rgba(255,255,255,0.08);
  --border:rgba(255,255,255,0.08);--border2:rgba(255,255,255,0.14);
  --primary:#7c6ee6;--primary-glow:rgba(124,110,230,0.3);--primary-light:#a89cf5;
  --accent:#22d3ee;--accent2:#f472b6;
  --text:#eeeef8;--text2:#8888aa;--text3:#4a4a6a;
  --success:#34d399;--error:#f87171;--warning:#fbbf24;
  --topbar-h:56px;--sidebar-w:268px;--studio-w:300px;
  --radius:12px;--radius-sm:8px;
  --font:'Inter',system-ui,sans-serif;--mono:'JetBrains Mono',monospace;
  --ease:0.22s cubic-bezier(0.4,0,0.2,1);
}
html{font-size:15px}
body{font-family:var(--font);background:var(--bg);color:var(--text);height:100dvh;overflow:hidden}

/* ── Topbar ─────────────────────────────────────────────── */
.topbar{
  height:var(--topbar-h);display:flex;align-items:center;justify-content:space-between;
  padding:0 18px;background:rgba(19,19,31,0.9);backdrop-filter:blur(20px);
  border-bottom:1px solid var(--border);position:sticky;top:0;z-index:100;
}
.topbar-left{display:flex;align-items:center;gap:12px}
.topbar-logo{width:28px;height:28px;background:linear-gradient(135deg,var(--primary),var(--accent));
  border-radius:8px;display:grid;place-items:center;color:#fff;box-shadow:0 0 16px var(--primary-glow)}
.topbar-logo svg{width:16px;height:16px}
.topbar-brand{font-weight:800;font-size:1rem;letter-spacing:-0.03em}
.topbar-divider{width:1px;height:18px;background:var(--border)}
.topbar-notebook-name{font-size:0.82rem;color:var(--text2);font-weight:500}
.topbar-right{display:flex;align-items:center;gap:10px}
.topbar-model-badge{display:flex;align-items:center;gap:6px;padding:5px 12px;border-radius:20px;
  background:var(--surface2);border:1px solid var(--border2);font-size:0.72rem;color:var(--text2);font-weight:500}
.model-dot{width:7px;height:7px;border-radius:50%;background:var(--success);box-shadow:0 0 6px var(--success)}
.topbar-icon-btn{width:32px;height:32px;border-radius:8px;background:var(--surface);border:1px solid var(--border);
  color:var(--text2);cursor:pointer;display:grid;place-items:center;transition:background var(--ease),color var(--ease)}
.topbar-icon-btn:hover{background:var(--surface2);color:var(--text)}
.topbar-icon-btn svg{width:16px;height:16px}
.topbar-avatar{width:30px;height:30px;border-radius:50%;background:linear-gradient(135deg,var(--primary),var(--accent));
  display:grid;place-items:center;font-weight:800;font-size:0.78rem;color:#fff;cursor:pointer}

/* ── App Shell ───────────────────────────────────────────── */
.app-shell{display:flex;height:calc(100dvh - var(--topbar-h));position:relative;z-index:1}

/* ── Sidebar ─────────────────────────────────────────────── */
.sidebar{
  width:var(--sidebar-w);min-width:var(--sidebar-w);
  background:rgba(19,19,31,0.95);backdrop-filter:blur(20px);
  border-right:1px solid var(--border);
  display:flex;flex-direction:column;gap:0;
  overflow-y:auto;overflow-x:hidden;
  transition:width var(--ease),min-width var(--ease),padding var(--ease);
  scrollbar-width:thin;scrollbar-color:var(--border) transparent;
}
.sidebar.collapsed{width:0;min-width:0;overflow:hidden}

.sidebar-section-header{
  display:flex;align-items:center;justify-content:space-between;
  padding:14px 16px 10px;border-bottom:1px solid var(--border);flex-shrink:0;
}
.sidebar-section-title{font-weight:700;font-size:0.85rem}
.sources-count-badge{
  background:var(--primary);color:#fff;border-radius:20px;
  padding:1px 8px;font-size:0.65rem;font-weight:700;
}

/* Upload zone */
.upload-section{padding:12px;flex-shrink:0}
.drop-zone{
  border:1.5px dashed var(--border2);border-radius:var(--radius);
  padding:16px 12px;text-align:center;cursor:pointer;
  background:var(--surface);transition:border-color var(--ease),background var(--ease);
  position:relative;overflow:hidden;
}
.drop-zone:hover,.drop-zone.drag-over{border-color:var(--primary);background:rgba(124,110,230,0.07)}
.drop-zone.drag-over .drop-icon{transform:translateY(-4px) scale(1.1)}
.drop-zone-inner{display:flex;flex-direction:column;align-items:center;gap:5px;pointer-events:none}
.drop-icon{width:36px;height:36px;border-radius:10px;
  background:linear-gradient(135deg,rgba(124,110,230,0.2),rgba(34,211,238,0.1));
  display:grid;place-items:center;color:var(--primary-light);
  transition:transform var(--ease);margin-bottom:2px}
.drop-icon svg{width:18px;height:18px}
.drop-title{font-size:0.8rem;font-weight:600;color:var(--text)}
.drop-sub{font-size:0.68rem;color:var(--text3)}
.btn-browse{
  margin-top:4px;font-size:0.7rem;font-weight:600;color:var(--primary-light);
  background:rgba(124,110,230,0.15);border:1px solid rgba(124,110,230,0.3);
  border-radius:20px;padding:3px 12px;cursor:pointer;pointer-events:all;
  transition:background var(--ease);
}
.btn-browse:hover{background:rgba(124,110,230,0.3);color:#fff}

/* Upload progress */
.upload-progress{padding:8px 0}
.upload-progress-bar-track{height:4px;border-radius:2px;background:var(--border);overflow:hidden}
.upload-progress-bar{height:100%;border-radius:2px;width:0%;
  background:linear-gradient(90deg,var(--primary),var(--accent));
  transition:width 0.4s ease;animation:pglow 1.5s ease infinite}
@keyframes pglow{0%,100%{opacity:1}50%{opacity:0.65}}
.upload-progress-label{font-size:0.68rem;color:var(--text2);margin-top:6px;text-align:center}

/* Multi-select toolbar */
.multi-select-toolbar{
  display:flex;align-items:center;gap:8px;padding:6px 12px;
  background:rgba(124,110,230,0.08);border-bottom:1px solid rgba(124,110,230,0.2);flex-shrink:0;
}
.multi-select-label{font-size:0.7rem;color:var(--primary-light);font-weight:600;flex:1}
.multi-select-action-btn{font-size:0.67rem;color:var(--text2);background:none;border:none;cursor:pointer;padding:2px 6px;
  border-radius:4px;transition:color var(--ease),background var(--ease)}
.multi-select-action-btn:hover{color:var(--text);background:var(--surface2)}

/* Docs list */
.docs-list{display:flex;flex-direction:column;gap:4px;padding:8px;flex:1}
.docs-empty{display:flex;flex-direction:column;align-items:center;gap:6px;
  padding:24px 12px;color:var(--text3);font-size:0.75rem;text-align:center}
.docs-empty svg{width:28px;height:28px;opacity:0.35}
.docs-empty-sub{font-size:0.68rem;color:var(--text3);margin-top:2px}
.doc-item{
  display:flex;align-items:center;gap:8px;padding:9px 10px;border-radius:var(--radius-sm);
  border:1px solid transparent;cursor:pointer;
  transition:background var(--ease),border-color var(--ease);
  animation:slideIn 0.2s ease;
}
@keyframes slideIn{from{opacity:0;transform:translateX(-10px)}to{opacity:1;transform:translateX(0)}}
.doc-item:hover{background:var(--surface);border-color:var(--border)}
.doc-item.selected{background:rgba(124,110,230,0.1);border-color:var(--primary)}
.doc-checkbox{
  width:16px;height:16px;border-radius:4px;border:1.5px solid var(--border2);
  background:var(--surface);cursor:pointer;flex-shrink:0;
  display:grid;place-items:center;transition:border-color var(--ease),background var(--ease);
}
.doc-checkbox.checked{background:var(--primary);border-color:var(--primary)}
.doc-checkbox.checked::after{content:'';width:9px;height:6px;
  border-left:2px solid #fff;border-bottom:2px solid #fff;
  transform:rotate(-45deg) translate(1px,-1px)}
.doc-file-icon{font-size:1.1rem;flex-shrink:0}
.doc-info{flex:1;overflow:hidden}
.doc-name{font-size:0.76rem;font-weight:500;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.doc-meta{font-size:0.62rem;color:var(--text3);margin-top:1px}
.doc-delete{
  width:22px;height:22px;border-radius:6px;background:transparent;border:none;
  cursor:pointer;color:var(--text3);display:grid;place-items:center;flex-shrink:0;
  transition:color var(--ease),background var(--ease);opacity:0;
}
.doc-item:hover .doc-delete{opacity:1}
.doc-delete:hover{color:var(--error);background:rgba(248,113,113,0.12)}
.doc-delete svg{width:12px;height:12px}

/* Active query pill */
.active-query-pill{
  display:flex;align-items:center;gap:7px;margin:8px;padding:8px 12px;
  border-radius:var(--radius-sm);background:rgba(124,110,230,0.12);
  border:1px solid rgba(124,110,230,0.3);font-size:0.72rem;color:var(--primary-light);font-weight:500;
}
.active-query-pill svg{width:13px;height:13px;flex-shrink:0}

/* ── Chat Main ────────────────────────────────────────────── */
.chat-main{flex:1;display:flex;flex-direction:column;overflow:hidden;min-width:0}
.chat-header{
  display:flex;align-items:center;gap:12px;padding:12px 18px;
  border-bottom:1px solid var(--border);background:rgba(19,19,31,0.7);
  backdrop-filter:blur(16px);flex-shrink:0;
}
.chat-header-title{font-weight:700;font-size:0.88rem;flex:1}
.chat-header-right{display:flex;align-items:center;gap:6px}
.btn-icon-sm{
  width:32px;height:32px;border-radius:8px;background:var(--surface);
  border:1px solid var(--border);color:var(--text2);cursor:pointer;
  display:grid;place-items:center;transition:background var(--ease),color var(--ease);
}
.btn-icon-sm:hover{background:var(--surface2);color:var(--text)}
.btn-icon-sm svg{width:15px;height:15px}

/* Messages */
.messages-area{
  flex:1;overflow-y:auto;padding:24px 20px;
  display:flex;flex-direction:column;
  scrollbar-width:thin;scrollbar-color:var(--border) transparent;
}
.messages-list{display:flex;flex-direction:column;gap:20px;padding-top:4px}

/* Welcome */
.welcome-state{
  flex:1;display:flex;flex-direction:column;
  align-items:center;justify-content:center;text-align:center;gap:14px;padding:40px 20px;
}
.welcome-graphic{position:relative;width:90px;height:90px;margin-bottom:6px}
.welcome-rings{position:absolute;inset:0}
.ring{position:absolute;border-radius:50%;border:1px solid var(--primary);animation:ringPulse 3s ease-in-out infinite}
.ring-1{inset:0;opacity:0.3}
.ring-2{inset:12px;opacity:0.2;animation-delay:0.5s}
.ring-3{inset:24px;opacity:0.1;animation-delay:1s}
@keyframes ringPulse{0%,100%{transform:scale(1);opacity:0.3}50%{transform:scale(1.06);opacity:0.6}}
.welcome-icon{position:absolute;inset:0;display:grid;place-items:center;color:var(--primary-light)}
.welcome-icon svg{width:36px;height:36px}
.welcome-title{font-size:1.5rem;font-weight:800;letter-spacing:-0.03em}
.welcome-sub{font-size:0.84rem;color:var(--text2);max-width:420px;line-height:1.65}
.welcome-chips{display:flex;flex-wrap:wrap;gap:8px;justify-content:center;margin-top:4px}
.chip{padding:4px 12px;border-radius:20px;font-size:0.72rem;font-weight:500;
  background:var(--surface2);border:1px solid var(--border2);color:var(--text2)}

/* Messages */
.message{display:flex;gap:10px;animation:msgIn 0.28s ease}
@keyframes msgIn{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}
.message.user{flex-direction:row-reverse}
.msg-avatar{width:32px;height:32px;border-radius:10px;display:grid;place-items:center;flex-shrink:0;font-size:0.78rem;font-weight:700}
.message.user .msg-avatar{background:linear-gradient(135deg,var(--primary),var(--accent));color:#fff}
.message.assistant .msg-avatar{background:linear-gradient(135deg,rgba(124,110,230,0.2),rgba(34,211,238,0.1));border:1px solid var(--border2);color:var(--primary-light)}
.message.assistant .msg-avatar svg{width:16px;height:16px}
.msg-body{max-width:74%;display:flex;flex-direction:column;gap:6px}
.message.user .msg-body{align-items:flex-end}
.msg-bubble{padding:11px 16px;border-radius:14px;font-size:0.875rem;line-height:1.7}
.message.user .msg-bubble{background:linear-gradient(135deg,var(--primary),#5c51cc);color:#fff;border-bottom-right-radius:4px;box-shadow:0 4px 20px var(--primary-glow)}
.message.assistant .msg-bubble{background:rgba(255,255,255,0.05);border:1px solid var(--border2);color:var(--text);border-bottom-left-radius:4px}
.msg-time{font-size:0.62rem;color:var(--text3)}
.stream-cursor{display:inline-block;width:2px;height:1em;background:var(--primary-light);margin-left:2px;vertical-align:text-bottom;animation:blink 0.8s step-end infinite}
@keyframes blink{0%,100%{opacity:1}50%{opacity:0}}

/* Markdown inside bubbles */
.msg-bubble h1,.msg-bubble h2,.msg-bubble h3{font-size:0.92rem;font-weight:700;margin:10px 0 5px;color:var(--primary-light)}
.msg-bubble ul,.msg-bubble ol{padding-left:20px;margin:6px 0}
.msg-bubble li{margin:3px 0}
.msg-bubble code{font-family:var(--mono);font-size:0.76rem;background:rgba(255,255,255,0.08);padding:1px 5px;border-radius:4px}
.msg-bubble strong{font-weight:600;color:var(--primary-light)}
.msg-bubble p+p{margin-top:8px}

/* Sources accordion */
.sources-wrap{margin-top:4px}
.sources-toggle{display:flex;align-items:center;gap:5px;font-size:0.68rem;color:var(--text3);cursor:pointer;background:none;border:none;padding:0;transition:color var(--ease)}
.sources-toggle:hover{color:var(--primary-light)}
.sources-toggle svg{width:11px;height:11px;transition:transform var(--ease)}
.sources-toggle.open svg{transform:rotate(180deg)}
.sources-list{display:none;flex-direction:column;gap:5px;margin-top:7px}
.sources-list.open{display:flex}
.source-chunk{padding:7px 10px;border-radius:6px;background:rgba(255,255,255,0.03);border:1px solid var(--border);font-size:0.7rem;color:var(--text2);line-height:1.5;font-family:var(--mono)}
.source-score{font-size:0.62rem;color:var(--accent);margin-bottom:3px;display:block}

/* Typing */
.typing-bubble{display:flex;align-items:center;gap:5px;padding:12px 16px;border-radius:14px;border-bottom-left-radius:4px;background:rgba(255,255,255,0.05);border:1px solid var(--border2);width:fit-content}
.dot{width:6px;height:6px;border-radius:50%;background:var(--primary);animation:bounce 1.2s ease infinite}
.dot:nth-child(2){animation-delay:0.2s}
.dot:nth-child(3){animation-delay:0.4s}
@keyframes bounce{0%,80%,100%{transform:scale(0.7);opacity:0.4}40%{transform:scale(1);opacity:1}}

/* Error */
.msg-error{display:flex;align-items:center;gap:8px;padding:10px 14px;border-radius:8px;background:rgba(248,113,113,0.08);border:1px solid rgba(248,113,113,0.25);font-size:0.8rem;color:var(--error)}

/* ── Input Area ───────────────────────────────────────────── */
.input-area{padding:14px 20px 18px;background:rgba(19,19,31,0.8);backdrop-filter:blur(20px);border-top:1px solid var(--border);flex-shrink:0}
.input-wrap{max-width:820px;margin:0 auto}
.suggestions-row{display:flex;gap:7px;flex-wrap:wrap;margin-bottom:10px}
.suggestion-chip{padding:4px 12px;border-radius:20px;font-size:0.7rem;color:var(--text2);background:var(--surface);border:1px solid var(--border);cursor:pointer;transition:border-color var(--ease),color var(--ease);white-space:nowrap}
.suggestion-chip:hover{border-color:var(--primary);color:var(--primary-light)}
.input-row{display:flex;gap:10px;align-items:flex-end}
.question-input{
  flex:1;padding:12px 16px;background:rgba(255,255,255,0.05);border:1px solid var(--border2);
  border-radius:var(--radius);color:var(--text);font-family:var(--font);font-size:0.875rem;
  resize:none;line-height:1.5;max-height:150px;overflow-y:auto;outline:none;
  transition:border-color var(--ease),box-shadow var(--ease);
}
.question-input:focus{border-color:var(--primary);box-shadow:0 0 0 3px var(--primary-glow)}
.question-input::placeholder{color:var(--text3)}
.question-input:disabled{opacity:0.4;cursor:not-allowed}
.btn-send{
  width:44px;height:44px;border-radius:var(--radius);
  background:linear-gradient(135deg,var(--primary),#5c51cc);
  border:none;color:#fff;cursor:pointer;display:grid;place-items:center;flex-shrink:0;
  box-shadow:0 4px 18px var(--primary-glow);
  transition:transform var(--ease),box-shadow var(--ease),opacity var(--ease);
}
.btn-send:hover:not(:disabled){transform:translateY(-2px);box-shadow:0 8px 26px var(--primary-glow)}
.btn-send:disabled{opacity:0.35;cursor:not-allowed}
.btn-send svg{width:17px;height:17px}
.input-hint{font-size:0.65rem;color:var(--text3);text-align:center;margin-top:8px}
.disclaimer{font-size:0.65rem;color:var(--text3);text-align:center;padding:6px 0 10px}

/* ── Studio Panel ─────────────────────────────────────────── */
.studio-panel{
  width:var(--studio-w);min-width:var(--studio-w);
  background:rgba(19,19,31,0.95);border-left:1px solid var(--border);
  padding:14px;display:flex;flex-direction:column;gap:16px;overflow-y:auto;
  scrollbar-width:thin;scrollbar-color:var(--border) transparent;
}
.studio-header{display:flex;align-items:center;justify-content:space-between;padding-bottom:10px;border-bottom:1px solid var(--border)}
.studio-title{font-weight:700;font-size:0.88rem}
.studio-empty{display:flex;flex-direction:column;align-items:center;gap:8px;padding:24px 12px;color:var(--text3);font-size:0.75rem;text-align:center}
.studio-empty svg{width:28px;height:28px;opacity:0.3}
.studio-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-sm);padding:12px}
.studio-card-label{font-size:0.62rem;font-weight:600;letter-spacing:0.08em;text-transform:uppercase;color:var(--text3);margin-bottom:4px}
.studio-card-value{font-size:0.8rem;font-weight:500;color:var(--text);word-break:break-all}
.studio-stats-grid{display:grid;grid-template-columns:1fr 1fr;gap:8px}
.studio-stat{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius-sm);padding:10px 12px}
.studio-stat-val{font-size:1.1rem;font-weight:700;color:var(--primary-light)}
.studio-stat-label{font-size:0.62rem;color:var(--text3);margin-top:2px}
.studio-pipeline{}
.pipeline-steps{display:flex;flex-direction:column;gap:7px}
.step{display:flex;align-items:flex-start;gap:8px}
.step-num{width:18px;height:18px;border-radius:50%;background:linear-gradient(135deg,var(--primary),var(--accent));font-size:0.58rem;font-weight:700;color:#fff;display:grid;place-items:center;flex-shrink:0;box-shadow:0 0 8px var(--primary-glow)}
.step-text{font-size:0.69rem;color:var(--text2);line-height:1.5;padding-top:2px}
.step-text code{font-family:var(--mono);font-size:0.65rem;background:rgba(255,255,255,0.07);padding:1px 4px;border-radius:3px}
.studio-sources{}
.studio-chunks-list{display:flex;flex-direction:column;gap:7px}
.studio-chunk-item{padding:8px;border-radius:6px;background:var(--surface);border:1px solid var(--border);font-size:0.68rem;color:var(--text2);line-height:1.5}
.studio-chunk-meta{font-size:0.6rem;color:var(--accent);margin-bottom:4px;display:flex;justify-content:space-between}
.studio-chunk-text{color:var(--text2);font-family:var(--mono);font-size:0.65rem;display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}

/* ── Toast ────────────────────────────────────────────────── */
.toast-container{position:fixed;bottom:22px;right:22px;z-index:999;display:flex;flex-direction:column;gap:8px}
.toast{
  display:flex;align-items:center;gap:10px;padding:11px 16px;border-radius:10px;min-width:240px;
  background:rgba(22,22,38,0.97);backdrop-filter:blur(20px);
  border:1px solid var(--border2);color:var(--text);
  font-size:0.8rem;font-weight:500;box-shadow:0 8px 30px rgba(0,0,0,0.5);
  animation:toastIn 0.3s cubic-bezier(0.175,0.885,0.32,1.275);
}
.toast.hide{animation:toastOut 0.25s ease forwards}
@keyframes toastIn{from{opacity:0;transform:translateX(28px)}to{opacity:1;transform:translateX(0)}}
@keyframes toastOut{from{opacity:1;transform:translateX(0)}to{opacity:0;transform:translateX(28px)}}
.toast-icon{font-size:0.95rem}
.toast.success .toast-icon::before{content:'✓'}
.toast.error .toast-icon::before{content:'✕'}
.toast.info .toast-icon::before{content:'ℹ'}
.toast.success{border-color:rgba(52,211,153,0.3)}
.toast.error{border-color:rgba(248,113,113,0.3)}

/* ── Scrollbars ───────────────────────────────────────────── */
::-webkit-scrollbar{width:4px}
::-webkit-scrollbar-track{background:transparent}
::-webkit-scrollbar-thumb{background:var(--border2);border-radius:2px}
::-webkit-scrollbar-thumb:hover{background:var(--text3)}

/* ── Responsive ───────────────────────────────────────────── */
@media(max-width:1100px){.studio-panel{display:none}}
@media(max-width:700px){
  :root{--sidebar-w:260px}
  .sidebar{position:absolute;left:0;top:0;bottom:0;z-index:50;box-shadow:4px 0 24px rgba(0,0,0,0.4)}
  .sidebar.collapsed{transform:translateX(-100%);width:var(--sidebar-w)}
  .messages-area{padding:16px 14px}
  .input-area{padding:12px 14px 14px}
  .msg-body{max-width:88%}
}