:root {
  --bg:            #0f1216;
  --bg-elev:       #161a22;
  --bg-elev-2:     #1d2230;
  --border:        #262c3a;
  --border-strong: #374055;
  --text:          #e8ebf2;
  --text-dim:      #9aa3b7;
  --text-muted:    #6b7487;
  --accent:        #7aa2ff;
  --accent-strong: #6e8fff;
  --accent-dim:    #3a4769;
  --graph:         #7aa2ff;
  --vector:        #8fd69b;
  --danger:        #ff7a90;
  --warn:          #ffc86b;
  --code-bg:       #0b0e13;
  --shadow:        0 1px 2px rgba(0,0,0,.4), 0 4px 12px rgba(0,0,0,.25);
  --radius:        10px;
  --radius-sm:     6px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Inter", "Segoe UI", sans-serif;
  font-size: 15px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body {
  display: grid;
  grid-template-rows: auto 1fr auto;
  height: 100vh;
  overflow: hidden;
}

/* ── Top bar ─────────────────────────────────────────────────────────── */

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 24px;
  border-bottom: 1px solid var(--border);
  background: var(--bg-elev);
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 10px;
}
.brand-mark {
  color: var(--accent);
  font-size: 22px;
  line-height: 1;
}
.brand-name {
  font-weight: 700;
  font-size: 17px;
  letter-spacing: -.01em;
}
.brand-sub {
  color: var(--text-muted);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: .08em;
}

.topbar-controls {
  display: flex;
  gap: 14px;
  align-items: center;
}
.reg-label {
  display: flex;
  gap: 8px;
  align-items: center;
  color: var(--text-dim);
  font-size: 13px;
}
.reg-label select {
  background: var(--bg-elev-2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 6px 10px;
  font: inherit;
}

/* ── Chat area ───────────────────────────────────────────────────────── */

.chat {
  overflow-y: auto;
  padding: 28px 24px 48px;
  scroll-behavior: smooth;
}
.chat > * + * { margin-top: 28px; }

.empty-state {
  max-width: 720px;
  margin: 80px auto 0;
  text-align: center;
  color: var(--text-dim);
}
.empty-state h1 {
  color: var(--text);
  font-size: 28px;
  margin: 0 0 16px;
  font-weight: 600;
  letter-spacing: -.01em;
}
.empty-state p {
  margin: 0 0 32px;
  font-size: 15px;
}
.empty-state strong { color: var(--text); }
.suggestions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}
.suggestion {
  text-align: left;
  background: var(--bg-elev);
  border: 1px solid var(--border);
  color: var(--text-dim);
  padding: 12px 14px;
  border-radius: var(--radius);
  font: inherit;
  cursor: pointer;
  transition: border-color .15s, background .15s, color .15s;
}
.suggestion:hover {
  border-color: var(--border-strong);
  color: var(--text);
  background: var(--bg-elev-2);
}

.message {
  max-width: 820px;
  margin: 0 auto;
}
.message + .message { margin-top: 32px; }
.message.user {
  display: flex;
  justify-content: flex-end;
}
.message.user .bubble {
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  padding: 10px 16px;
  border-radius: 18px;
  max-width: 70%;
  color: var(--text);
}

.message.assistant {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 18px 18px;
  box-shadow: var(--shadow);
}

/* ── Backend toggle pill ─────────────────────────────────────────────── */

.backend-toggle {
  display: inline-flex;
  gap: 0;
  border: 1px solid var(--border-strong);
  border-radius: 999px;
  padding: 3px;
  background: var(--bg-elev-2);
  font-size: 12px;
  margin-bottom: 12px;
}
.backend-toggle button {
  background: transparent;
  color: var(--text-dim);
  border: 0;
  padding: 6px 14px;
  border-radius: 999px;
  cursor: pointer;
  font: inherit;
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  transition: background .15s, color .15s;
}
.backend-toggle button .dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--text-muted);
  display: inline-block;
}
.backend-toggle button[data-backend="graph"] .dot   { background: var(--graph); }
.backend-toggle button[data-backend="vector"] .dot  { background: var(--vector); }
.backend-toggle button.active {
  background: var(--bg);
  color: var(--text);
  box-shadow: inset 0 0 0 1px var(--border);
}
.backend-toggle button[data-state="streaming"] .dot {
  animation: pulse 1.2s ease-in-out infinite;
}
.backend-toggle button[data-state="refused"] .dot {
  background: var(--danger);
}
.backend-toggle button[data-state="error"] .dot {
  background: var(--danger);
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50%      { opacity: .4; transform: scale(1.3); }
}

/* ── Thinking drawer ─────────────────────────────────────────────────── */

.thinking {
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg-elev-2);
  margin-bottom: 14px;
  overflow: hidden;
}
.thinking-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 12px;
  cursor: pointer;
  color: var(--text-dim);
  font-size: 13px;
  user-select: none;
}
.thinking-header:hover { color: var(--text); }
.thinking-header .chev {
  font-size: 10px;
  transition: transform .15s;
  display: inline-block;
  margin-right: 6px;
}
.thinking[data-open="true"] .thinking-header .chev {
  transform: rotate(90deg);
}
.thinking-header .counters {
  color: var(--text-muted);
  font-size: 12px;
  font-variant-numeric: tabular-nums;
}
.thinking-body {
  display: none;
  padding: 0 12px 10px 30px;
  color: var(--text-dim);
  font-size: 13px;
  border-top: 1px solid var(--border);
}
.thinking[data-open="true"] .thinking-body { display: block; padding-top: 10px; }
.thinking-step {
  margin: 0;
  padding: 3px 0;
  display: flex;
  gap: 10px;
  align-items: baseline;
  animation: fade-in .2s ease-out;
}
.thinking-step .time {
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
  font-size: 11px;
  min-width: 48px;
}
.thinking-step.error { color: var(--danger); }
.thinking-step.refused { color: var(--warn); }
.thinking-step code {
  font-family: "SF Mono", "Menlo", monospace;
  color: var(--text);
  background: var(--code-bg);
  padding: 1px 4px;
  border-radius: 3px;
  font-size: 12px;
}
@keyframes fade-in {
  from { opacity: 0; transform: translateY(2px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ── Answer content ──────────────────────────────────────────────────── */

.answer {
  color: var(--text);
  font-size: 15px;
  line-height: 1.6;
}
.answer.refused {
  color: var(--warn);
  font-style: italic;
}
.answer .typing-cursor::after {
  content: '▍';
  color: var(--accent);
  animation: blink 1s steps(2) infinite;
  margin-left: 2px;
}
@keyframes blink { 50% { opacity: 0; } }

.answer p, .answer ol, .answer ul { margin: 0 0 10px; }
.answer ol, .answer ul { padding-left: 24px; }
.answer li { margin: 3px 0; }
.answer code {
  font-family: "SF Mono", "Menlo", monospace;
  background: var(--code-bg);
  padding: 1px 4px;
  border-radius: 3px;
  font-size: 13px;
}
.answer pre {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 12px;
  overflow-x: auto;
}
.answer pre code { background: transparent; padding: 0; }
.answer strong { color: var(--text); }
.answer h1, .answer h2, .answer h3 {
  color: var(--text);
  font-weight: 600;
  margin: 16px 0 8px;
  font-size: 16px;
}

/* Inline citation styling — [Article 6(1)], [Section 4] etc. */
.answer a.cite,
.answer .cite {
  color: var(--accent);
  background: rgba(122,162,255,0.08);
  border: 1px solid rgba(122,162,255,0.25);
  padding: 0 5px;
  border-radius: 4px;
  font-size: 12px;
  font-weight: 500;
  white-space: nowrap;
}

.chunks-summary {
  color: var(--text-muted);
  font-size: 12px;
  margin-top: 14px;
  padding-top: 10px;
  border-top: 1px dashed var(--border);
}

/* ── Feedback strip ──────────────────────────────────────────────────── */

.feedback {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px dashed var(--border);
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: 13px;
  color: var(--text-dim);
}
.feedback.hidden { display: none; }

.feedback-row {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.feedback-label {
  color: var(--text-muted);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: .06em;
  margin-right: 4px;
}

.thumb-group {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 2px;
}
.thumb-group .thumb-label {
  font-size: 11px;
  color: var(--text-muted);
  padding: 0 6px 0 8px;
}
.thumb-group .thumb-label[data-backend="graph"]  { color: var(--graph); }
.thumb-group .thumb-label[data-backend="vector"] { color: var(--vector); }
.thumb {
  background: transparent;
  border: 0;
  color: var(--text-dim);
  cursor: pointer;
  padding: 3px 7px;
  border-radius: 999px;
  font-size: 14px;
  transition: background .12s, color .12s;
  line-height: 1;
}
.thumb:hover { color: var(--text); background: var(--bg); }
.thumb.active[data-value="1"]  { background: rgba(143,214,155,0.18); color: var(--vector); }
.thumb.active[data-value="-1"] { background: rgba(255,122,144,0.18); color: var(--danger); }

.pref-group {
  display: inline-flex;
  gap: 0;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 2px;
  background: var(--bg-elev-2);
}
.pref-group button {
  background: transparent;
  border: 0;
  color: var(--text-dim);
  padding: 4px 12px;
  font: inherit;
  font-size: 12px;
  border-radius: 999px;
  cursor: pointer;
  transition: background .12s, color .12s;
}
.pref-group button:hover { color: var(--text); }
.pref-group button.active {
  background: var(--bg);
  color: var(--text);
  box-shadow: inset 0 0 0 1px var(--border-strong);
}

.feedback-note {
  flex: 1 1 240px;
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: var(--radius-sm);
  padding: 6px 10px;
  font: inherit;
  font-size: 13px;
  min-width: 180px;
  resize: vertical;
  min-height: 28px;
  max-height: 120px;
}
.feedback-note:focus {
  outline: none;
  border-color: var(--accent-strong);
}

.feedback-submit {
  background: var(--accent-strong);
  color: #0b0e13;
  border: 0;
  border-radius: var(--radius-sm);
  padding: 6px 14px;
  font: inherit;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
}
.feedback-submit:hover  { background: var(--accent); }
.feedback-submit:disabled {
  background: var(--accent-dim);
  color: var(--text-muted);
  cursor: not-allowed;
}

.feedback-status {
  font-size: 12px;
  color: var(--text-muted);
}
.feedback-status.ok    { color: var(--vector); }
.feedback-status.error { color: var(--danger); }

/* ── Composer ───────────────────────────────────────────────────────── */

.composer {
  border-top: 1px solid var(--border);
  background: var(--bg-elev);
  padding: 14px 24px 16px;
}
#composer-form {
  display: flex;
  gap: 8px;
  align-items: flex-end;
  max-width: 820px;
  margin: 0 auto;
}
#composer-input {
  flex: 1;
  background: var(--bg-elev-2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 12px 14px;
  font: inherit;
  resize: none;
  min-height: 44px;
  max-height: 200px;
  line-height: 1.4;
}
#composer-input:focus {
  outline: none;
  border-color: var(--accent-strong);
  box-shadow: 0 0 0 3px rgba(110,143,255,.15);
}
#composer-send, #composer-stop {
  background: var(--accent-strong);
  color: #0b0e13;
  border: 0;
  border-radius: var(--radius);
  padding: 0 18px;
  height: 44px;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  transition: background .15s;
}
#composer-send:hover { background: var(--accent); }
#composer-send:disabled {
  background: var(--accent-dim);
  color: var(--text-muted);
  cursor: not-allowed;
}
#composer-stop {
  background: var(--danger);
  color: #0b0e13;
}
.hidden { display: none !important; }

.composer-hint {
  text-align: center;
  margin-top: 8px;
  color: var(--text-muted);
  font-size: 12px;
  max-width: 820px;
  margin-left: auto;
  margin-right: auto;
}

/* ── Tight scrollbar ─────────────────────────────────────────────────── */

.chat::-webkit-scrollbar { width: 10px; }
.chat::-webkit-scrollbar-track { background: transparent; }
.chat::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 5px;
}
.chat::-webkit-scrollbar-thumb:hover { background: var(--border-strong); }

/* ── View-chunks button (inside retrieval step) ──────────────────────── */

.view-chunks-btn {
  margin-left: 8px;
  padding: 2px 8px;
  border: 1px solid var(--border-strong);
  background: var(--bg-elev-2);
  color: var(--accent);
  border-radius: 999px;
  font-size: 11px;
  cursor: pointer;
  transition: background .12s, border-color .12s;
}
.view-chunks-btn:hover {
  background: var(--accent-dim);
  border-color: var(--accent);
}

/* ── Chunks modal ────────────────────────────────────────────────────── */

.chunks-modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.62);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: 24px;
  backdrop-filter: blur(2px);
}
.chunks-modal {
  background: var(--bg-elev);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  width: min(960px, 100%);
  max-height: 90vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
.chunks-modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 18px;
  border-bottom: 1px solid var(--border);
  background: var(--bg-elev-2);
}
.chunks-modal-header h2 {
  margin: 0;
  font-size: 15px;
  font-weight: 600;
}
.chunks-modal-header .muted {
  color: var(--text-muted);
  font-weight: 400;
  font-size: 13px;
}
.chunks-modal-close {
  background: transparent;
  border: none;
  color: var(--text-dim);
  font-size: 22px;
  line-height: 1;
  cursor: pointer;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
}
.chunks-modal-close:hover {
  background: var(--bg-elev);
  color: var(--text);
}
.chunks-modal-body {
  padding: 14px 18px 18px;
  overflow-y: auto;
  flex: 1;
}
.chunk-item {
  padding: 12px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  margin-bottom: 10px;
  background: var(--bg);
}
.chunk-item:last-child { margin-bottom: 0; }
.chunk-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 10px;
  margin-bottom: 6px;
  font-size: 12px;
  color: var(--text-dim);
}
.chunk-idx {
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
}
.chunk-id {
  color: var(--accent);
  background: var(--code-bg);
  padding: 1px 6px;
  border-radius: 4px;
  font-size: 11.5px;
}
.chunk-meta-item {
  color: var(--text-muted);
  font-size: 11.5px;
}
.chunk-meta-item code {
  color: var(--text-dim);
  background: var(--code-bg);
  padding: 0 4px;
  border-radius: 3px;
}
.chunk-summary {
  color: var(--text-dim);
  font-size: 13px;
  margin-bottom: 6px;
}
.chunk-text {
  color: var(--text);
  font-size: 13.5px;
  white-space: pre-wrap;
  word-break: break-word;
  max-height: 240px;
  overflow-y: auto;
  padding: 8px 10px;
  background: var(--code-bg);
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
}
.chunk-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 8px;
}
.chunk-tag {
  font-size: 10.5px;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--accent-dim);
  color: var(--accent);
  border: 1px solid var(--border-strong);
}
.chunks-modal-body::-webkit-scrollbar,
.chunk-text::-webkit-scrollbar { width: 8px; }
.chunks-modal-body::-webkit-scrollbar-thumb,
.chunk-text::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 4px;
}