:root {
  --bg: #0f1115;
  --bg-elev: #161922;
  --bg-elev-2: #1d2230;
  --border: #262b39;
  --border-strong: #353c4d;
  --text: #e8eaed;
  --text-dim: #9aa0ad;
  --text-mute: #6b7180;
  --accent: #6e7cff;
  --accent-hover: #8290ff;
  --accent-soft: rgba(110, 124, 255, 0.12);
  --danger: #e05656;
  --success: #4ec9a0;
  --warning: #d8a64f;
  --user-bubble: #232838;
  --code-bg: #0c0e14;
  --tool-bg: #1a2034;
  --tool-border: #2a3454;
  --radius: 10px;
  --radius-sm: 6px;
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SF Mono", Menlo, Monaco, Consolas, "Roboto Mono", monospace;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 15px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

button {
  font-family: inherit;
  font-size: 14px;
  cursor: pointer;
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  transition: background 0.12s, border-color 0.12s, color 0.12s;
}
button:hover { background: var(--bg-elev-2); border-color: var(--border-strong); }
button.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: white;
}
button.primary:hover { background: var(--accent-hover); border-color: var(--accent-hover); }
button.ghost { background: transparent; border-color: var(--border); }
button.danger { background: var(--danger); border-color: var(--danger); color: white; }
button.danger:hover { background: #c14444; border-color: #c14444; }
button.icon { padding: 6px 8px; }

input, textarea, select {
  font-family: inherit;
  font-size: 14px;
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 8px 10px;
  width: 100%;
}
input:focus, textarea:focus, select:focus {
  outline: none;
  border-color: var(--accent);
}

code, pre { font-family: var(--font-mono); }

/* ============ Layout ============ */
#app {
  display: grid;
  grid-template-columns: 260px 1fr;
  height: 100vh;
  width: 100vw;
  overflow: hidden;
}

/* ============ Sidebar ============ */
#sidebar {
  background: var(--bg-elev);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  min-width: 0;
}
.sidebar-header {
  padding: 14px;
  border-bottom: 1px solid var(--border);
}
.sidebar-header button { width: 100%; }
.chat-list {
  flex: 1;
  overflow-y: auto;
  padding: 8px;
}
.chat-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 13.5px;
  color: var(--text-dim);
  margin-bottom: 2px;
}
.chat-item:hover { background: var(--bg-elev-2); color: var(--text); }
.chat-item.active { background: var(--accent-soft); color: var(--text); }
.chat-item-title {
  flex: 1;
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
}
.chat-item-delete {
  visibility: hidden;
  background: none;
  border: none;
  padding: 2px 6px;
  color: var(--text-mute);
  font-size: 14px;
}
.chat-item:hover .chat-item-delete { visibility: visible; }
.chat-item-delete:hover { color: var(--danger); background: none; }

.sidebar-footer {
  padding: 10px;
  border-top: 1px solid var(--border);
}
.sidebar-footer button { width: 100%; }

/* ============ Main ============ */
#main {
  display: flex;
  flex-direction: column;
  min-width: 0;
  height: 100vh;
}
#topbar {
  padding: 12px 24px;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--bg);
}
#chat-title {
  font-weight: 500;
  font-size: 15px;
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
}
.topbar-right { display: flex; gap: 8px; align-items: center; }
.indicator {
  font-size: 12px;
  color: var(--text-dim);
  padding: 4px 10px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--bg-elev);
}
.indicator.ok { color: var(--success); border-color: rgba(78, 201, 160, 0.3); }
.indicator.warn { color: var(--warning); border-color: rgba(216, 166, 79, 0.3); }

/* ============ Messages ============ */
.messages {
  flex: 1;
  overflow-y: auto;
  padding: 24px 0;
}
.empty-state {
  text-align: center;
  margin-top: 20vh;
  color: var(--text-dim);
}
.empty-state h1 { font-size: 28px; margin: 0 0 8px; color: var(--text); }
.empty-state p { font-size: 14px; }

.msg {
  max-width: 760px;
  margin: 0 auto 20px;
  padding: 0 24px;
}
.msg-row { display: flex; gap: 14px; align-items: flex-start; }
.msg-avatar {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 600;
  background: var(--bg-elev-2);
  margin-top: 2px;
}
.msg.user .msg-avatar { background: var(--accent); color: white; }
.msg.assistant .msg-avatar { background: #2d3344; color: var(--text); }
.msg.tool .msg-avatar { background: var(--tool-bg); color: var(--accent); }

.msg-content {
  flex: 1;
  min-width: 0;
  word-wrap: break-word;
  overflow-wrap: anywhere;
}
.msg-content > *:first-child { margin-top: 0; }
.msg-content > *:last-child { margin-bottom: 0; }
.msg-content p { margin: 0.6em 0; }
.msg-content h1, .msg-content h2, .msg-content h3, .msg-content h4 {
  margin: 1em 0 0.4em;
  font-weight: 600;
}
.msg-content h1 { font-size: 1.4em; }
.msg-content h2 { font-size: 1.2em; }
.msg-content h3 { font-size: 1.08em; }
.msg-content ul, .msg-content ol { margin: 0.5em 0; padding-left: 1.6em; }
.msg-content li { margin: 0.2em 0; }
.msg-content blockquote {
  border-left: 3px solid var(--border-strong);
  padding-left: 12px;
  color: var(--text-dim);
  margin: 0.6em 0;
}
.msg-content a { color: var(--accent); }
.msg-content code:not(pre code) {
  background: var(--code-bg);
  padding: 1px 5px;
  border-radius: 4px;
  font-size: 0.9em;
  border: 1px solid var(--border);
}
.msg-content pre {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 12px 14px;
  overflow-x: auto;
  font-size: 13px;
  line-height: 1.5;
  margin: 0.8em 0;
}
.msg-content pre code { background: none; padding: 0; border: none; }
.msg-content table {
  border-collapse: collapse;
  margin: 0.8em 0;
}
.msg-content th, .msg-content td {
  border: 1px solid var(--border);
  padding: 6px 10px;
}
.msg-content th { background: var(--bg-elev); font-weight: 600; }

.msg-cursor {
  display: inline-block;
  width: 7px;
  height: 1em;
  background: var(--text);
  vertical-align: -2px;
  margin-left: 2px;
  animation: blink 1s steps(2, end) infinite;
}
@keyframes blink { 50% { opacity: 0; } }

/* ============ Tool calls ============ */
.tool-call {
  border: 1px solid var(--tool-border);
  background: var(--tool-bg);
  border-radius: var(--radius);
  margin: 10px 0;
  font-size: 13px;
  overflow: hidden;
}
.tool-call-header {
  padding: 8px 12px;
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  user-select: none;
}
.tool-call-header:hover { background: rgba(255,255,255,0.03); }
.tool-call-icon {
  width: 18px; height: 18px;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
}
.tool-call-name {
  font-family: var(--font-mono);
  font-size: 12.5px;
  font-weight: 500;
  color: var(--accent);
}
.tool-call-status { margin-left: auto; font-size: 12px; color: var(--text-dim); }
.tool-call.error { border-color: rgba(224, 86, 86, 0.5); }
.tool-call.error .tool-call-name { color: var(--danger); }
.tool-call.running .tool-call-status { color: var(--warning); }
.tool-call.done .tool-call-status { color: var(--success); }

.tool-call-body {
  border-top: 1px solid var(--tool-border);
  padding: 10px 12px;
  font-family: var(--font-mono);
  font-size: 12px;
}
.tool-call-body[hidden] { display: none; }
.tool-call-section { margin: 0; }
.tool-call-section + .tool-call-section { margin-top: 10px; }
.tool-call-section-label {
  color: var(--text-mute);
  text-transform: uppercase;
  font-size: 10px;
  letter-spacing: 0.06em;
  margin-bottom: 4px;
}
.tool-call-section pre {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 8px;
  white-space: pre-wrap;
  word-break: break-word;
  margin: 0;
  max-height: 360px;
  overflow: auto;
}

.spinner {
  width: 12px; height: 12px;
  border: 2px solid var(--border-strong);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  display: inline-block;
  vertical-align: middle;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ============ Composer ============ */
.composer {
  border-top: 1px solid var(--border);
  padding: 16px 24px 20px;
  display: flex;
  gap: 10px;
  align-items: flex-end;
  background: var(--bg);
}
.composer textarea {
  flex: 1;
  resize: none;
  max-height: 200px;
  line-height: 1.4;
  padding: 12px 14px;
  border-radius: var(--radius);
  background: var(--bg-elev);
  border: 1px solid var(--border);
}
.composer textarea:focus { border-color: var(--accent); }
.composer button { padding: 10px 18px; height: fit-content; }

/* ============ Modal ============ */
.modal { position: fixed; inset: 0; display: flex; align-items: center; justify-content: center; z-index: 50; }
.modal[hidden] { display: none; }
.modal-backdrop {
  position: absolute; inset: 0;
  background: rgba(0, 0, 0, 0.55);
}
.modal-window {
  position: relative;
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  width: 720px;
  max-width: calc(100vw - 32px);
  max-height: 86vh;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow);
}
.modal-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.modal-header h2 { margin: 0; font-size: 16px; font-weight: 600; }
.close-btn { background: none; border: none; font-size: 18px; padding: 4px 8px; color: var(--text-dim); }
.close-btn:hover { color: var(--text); background: none; }

.modal-tabs {
  display: flex;
  padding: 0 12px;
  border-bottom: 1px solid var(--border);
  gap: 4px;
}
.tab {
  background: none;
  border: none;
  padding: 12px 14px;
  color: var(--text-dim);
  border-bottom: 2px solid transparent;
  border-radius: 0;
  font-size: 13.5px;
}
.tab:hover { color: var(--text); background: none; }
.tab.active { color: var(--text); border-bottom-color: var(--accent); }

.modal-body { padding: 20px; overflow-y: auto; flex: 1; }
.tab-panel { display: none; }
.tab-panel.active { display: block; }

.hint { color: var(--text-dim); font-size: 13px; margin: 0 0 14px; }
.hint code { background: var(--code-bg); padding: 1px 5px; border-radius: 4px; font-size: 12px; }

.modal-footer {
  padding: 14px 20px;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: flex-end;
}

.field { display: flex; flex-direction: column; gap: 6px; margin-bottom: 14px; }
.field > span { font-size: 12px; color: var(--text-dim); font-weight: 500; }
.row { display: flex; gap: 14px; }
.row .field { flex: 1; }

/* Cards for providers/MCP */
.entity-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px;
  margin-bottom: 12px;
}
.entity-card-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
}
.entity-card-name { font-weight: 600; font-size: 14px; }
.entity-card-actions { display: flex; gap: 6px; align-items: center; }
.entity-status { font-size: 12px; color: var(--text-dim); }
.entity-status.ok { color: var(--success); }
.entity-status.err { color: var(--danger); }

.toggle {
  position: relative;
  display: inline-block;
  width: 36px; height: 20px;
}
.toggle input { opacity: 0; width: 0; height: 0; }
.toggle .slider {
  position: absolute; inset: 0;
  background: var(--border-strong);
  border-radius: 999px;
  transition: 0.2s;
  cursor: pointer;
}
.toggle .slider::before {
  content: '';
  position: absolute;
  width: 14px; height: 14px;
  left: 3px; top: 3px;
  background: white;
  border-radius: 50%;
  transition: 0.2s;
}
.toggle input:checked + .slider { background: var(--accent); }
.toggle input:checked + .slider::before { transform: translateX(16px); }

.active-radio {
  display: flex; align-items: center; gap: 6px;
  font-size: 12px; color: var(--text-dim);
}
.active-radio input { width: auto; }

.tools-list {
  display: flex; flex-wrap: wrap; gap: 4px;
  margin-top: 8px;
}
.tool-chip {
  background: var(--bg-elev-2);
  padding: 2px 8px;
  border-radius: 999px;
  font-size: 11px;
  font-family: var(--font-mono);
  color: var(--text-dim);
}

/* Scrollbars */
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 5px; }
::-webkit-scrollbar-thumb:hover { background: #4a536b; }

@media (max-width: 720px) {
  #app { grid-template-columns: 1fr; }
  #sidebar { display: none; }
  .msg { padding: 0 16px; }
  .composer { padding: 12px 16px 16px; }
}