/* ── Design Tokens ─────────────────────────────────────────── */
:root {
  --radius: 12px;
  --radius-sm: 8px;
  --transition: 200ms cubic-bezier(0.4, 0, 0.2, 1);
  --font: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
  --sidebar-width: 280px;
  --navbar-height: 56px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.12);
}

[data-theme="dark"] {
  --bg: #0b0d14;
  --surface: #141720;
  --surface-2: #1c2033;
  --surface-3: #252a44;
  --border: #262b44;
  --border-light: #1e2340;
  --text: #e8ecf4;
  --text-muted: #7f88a8;
  --text-dim: #4a5278;
  --primary: #7c73ff;
  --primary-hover: #6a61ee;
  --primary-soft: rgba(124, 115, 255, 0.12);
  --primary-fg: #fff;
  --sidebar-bg: #0c0e18;
  --user-bubble: linear-gradient(135deg, #2a3f7a 0%, #1e3a5f 100%);
  --user-bubble-text: #dbeafe;
  --scrollbar: #1e2340;
  --scrollbar-hover: #2d3358;
  --code-bg: #0d1117;
  --input-bg: #141720;
  --danger: #ef4444;
  --danger-hover: #dc2626;
  --danger-soft: rgba(239, 68, 68, 0.12);
  --success: #22c55e;
  --success-soft: rgba(34, 197, 94, 0.12);
  --warning: #f59e0b;
  --glow-primary: 0 0 20px rgba(124, 115, 255, 0.15);
}

[data-theme="light"] {
  --bg: #f4f6fc;
  --surface: #ffffff;
  --surface-2: #eef1f8;
  --surface-3: #e2e7f2;
  --border: #dce1ed;
  --border-light: #e8ecf4;
  --text: #0f172a;
  --text-muted: #64748b;
  --text-dim: #94a3b8;
  --primary: #6c63ff;
  --primary-hover: #5a52e0;
  --primary-soft: rgba(108, 99, 255, 0.08);
  --primary-fg: #fff;
  --sidebar-bg: #ffffff;
  --user-bubble: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
  --user-bubble-text: #ffffff;
  --scrollbar: #d1d6e4;
  --scrollbar-hover: #b8bfd0;
  --code-bg: #f1f5f9;
  --input-bg: #ffffff;
  --danger: #ef4444;
  --danger-hover: #dc2626;
  --danger-soft: rgba(239, 68, 68, 0.08);
  --success: #16a34a;
  --success-soft: rgba(22, 163, 74, 0.08);
  --warning: #f59e0b;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.06);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.08);
  --glow-primary: 0 0 20px rgba(108, 99, 255, 0.08);
}

/* ── Reset & Base ───────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  transition: background var(--transition), color var(--transition);
}
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }
button { cursor: pointer; border: none; background: none; font: inherit; color: inherit; }
input, textarea, select {
  font: inherit;
  color: var(--text);
  background: var(--input-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
}
input:focus, textarea:focus, select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-soft);
}
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--scrollbar); border-radius: 99px; }
::-webkit-scrollbar-thumb:hover { background: var(--scrollbar-hover); }

/* ── Layout ─────────────────────────────────────────────────── */
.app-layout {
  display: flex;
  height: 100vh;
  overflow: hidden;
}

/* ── Navbar ─────────────────────────────────────────────────── */
.navbar {
  height: var(--navbar-height);
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1.25rem;
  gap: 1rem;
  flex-shrink: 0;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}
.navbar-brand {
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--text);
  letter-spacing: -0.01em;
}
.navbar-center { display: flex; align-items: center; gap: 0.75rem; }
.navbar-right { display: flex; align-items: center; gap: 0.5rem; }
.token-badge {
  font-size: 0.7rem;
  color: var(--text-muted);
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 99px;
  padding: 3px 10px;
  white-space: nowrap;
  font-weight: 500;
  letter-spacing: 0.01em;
}

/* ── Sidebar ─────────────────────────────────────────────────── */
.sidebar {
  width: var(--sidebar-width);
  background: var(--sidebar-bg);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  overflow: hidden;
}
.sidebar-header {
  padding: 0.75rem;
  border-bottom: 1px solid var(--border);
}
.sidebar-list {
  flex: 1;
  overflow-y: auto;
  padding: 0.5rem;
}
.sidebar-list::-webkit-scrollbar { width: 4px; }
.sidebar-footer {
  padding: 0.625rem 0.75rem;
  border-top: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 0.125rem;
}
.conv-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.625rem 0.75rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition);
  position: relative;
  margin-bottom: 2px;
}
.conv-item:hover { background: var(--surface-2); }
.conv-item.active { background: var(--surface-2); }
.conv-item.active::before {
  content: '';
  position: absolute;
  left: 0;
  top: 25%;
  height: 50%;
  width: 3px;
  background: var(--primary);
  border-radius: 0 3px 3px 0;
}
.conv-item-title {
  flex: 1;
  font-size: 0.85rem;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  color: var(--text);
  font-weight: 450;
}
.conv-item-delete {
  opacity: 0;
  color: var(--text-dim);
  font-size: 0.85rem;
  padding: 2px 4px;
  border-radius: 4px;
  cursor: pointer;
  transition: opacity var(--transition), color var(--transition), background var(--transition);
}
.conv-item:hover .conv-item-delete { opacity: 1; }
.conv-item-delete:hover { color: var(--danger); background: var(--danger-soft); }

/* ── Main Chat Area ─────────────────────────────────────────── */
.chat-wrapper {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
.messages-area {
  flex: 1;
  overflow-y: auto;
  padding: 1.5rem 1rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}
.messages-area::-webkit-scrollbar { width: 6px; }
.message {
  max-width: 768px;
  width: 100%;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  animation: messageIn 0.25s ease-out;
}
@keyframes messageIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}
.message.user { align-items: flex-end; }
.message.assistant { align-items: flex-start; }
.message-bubble {
  padding: 0.75rem 1.125rem;
  border-radius: var(--radius);
  font-size: 0.9375rem;
  line-height: 1.65;
  max-width: 85%;
  word-break: break-word;
  position: relative;
}
.message.user .message-bubble {
  background: var(--user-bubble);
  color: var(--user-bubble-text);
  border: none;
  border-bottom-right-radius: 4px;
  box-shadow: var(--shadow-sm);
}
.message.assistant .message-bubble {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text);
  border-bottom-left-radius: 4px;
  box-shadow: var(--shadow-sm);
}
.message-bubble pre {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.875rem 1rem;
  overflow-x: auto;
  margin: 0.625rem 0;
  font-size: 0.85rem;
}
.message-bubble code {
  font-family: var(--font-mono);
  font-size: 0.875em;
}
.message-bubble p { margin-bottom: 0.625rem; }
.message-bubble p:last-child { margin-bottom: 0; }
.message-bubble ul, .message-bubble ol { padding-left: 1.25rem; margin-bottom: 0.5rem; }
.message-bubble li { margin-bottom: 0.25rem; }
.message-bubble blockquote {
  border-left: 3px solid var(--primary);
  padding-left: 0.75rem;
  color: var(--text-muted);
  margin: 0.5rem 0;
}
.message-bubble table {
  border-collapse: collapse;
  margin: 0.5rem 0;
  font-size: 0.875rem;
  width: 100%;
}
.message-bubble th, .message-bubble td {
  border: 1px solid var(--border);
  padding: 0.375rem 0.625rem;
  text-align: left;
}
.message-bubble th { background: var(--surface-2); font-weight: 600; }
.message-image {
  max-width: 280px;
  max-height: 280px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  margin-bottom: 0.5rem;
  object-fit: cover;
}
.streaming-cursor::after {
  content: '▌';
  animation: blink 0.8s step-end infinite;
  margin-left: 1px;
}
@keyframes blink { 50% { opacity: 0; } }

/* ── Input Bar ───────────────────────────────────────────────── */
.input-bar {
  padding: 0.75rem 1rem 1rem;
  background: var(--bg);
  border-top: 1px solid var(--border);
}
.input-inner {
  max-width: 768px;
  margin: 0 auto;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  display: flex;
  align-items: flex-end;
  gap: 0.5rem;
  padding: 0.5rem 0.5rem 0.5rem 1rem;
  transition: border-color var(--transition), box-shadow var(--transition);
  box-shadow: var(--shadow-sm);
}
.input-inner:focus-within {
  border-color: var(--primary);
  box-shadow: var(--glow-primary);
}
.input-image-preview {
  display: none;
  max-height: 80px;
  border-radius: var(--radius-sm);
  margin-bottom: 0.375rem;
  object-fit: cover;
}
.message-input {
  flex: 1;
  background: none;
  border: none;
  resize: none;
  min-height: 24px;
  max-height: 160px;
  font-size: 0.9375rem;
  line-height: 1.5;
  padding: 0;
  outline: none;
  color: var(--text);
}
.message-input::placeholder { color: var(--text-dim); }
.input-actions {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  flex-shrink: 0;
}

/* ── Buttons ─────────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.375rem;
  padding: 0.5rem 1rem;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 500;
  transition: all var(--transition);
  cursor: pointer;
  white-space: nowrap;
}
.btn-primary {
  background: var(--primary);
  color: var(--primary-fg);
}
.btn-primary:hover { background: var(--primary-hover); transform: translateY(-1px); }
.btn-primary:active { transform: translateY(0); }
.btn-primary:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}
.btn-ghost {
  background: transparent;
  color: var(--text-muted);
  border: 1px solid transparent;
}
.btn-ghost:hover { background: var(--surface-2); color: var(--text); }
.btn-danger {
  background: var(--danger);
  color: #fff;
}
.btn-danger:hover { background: var(--danger-hover); }
.btn-icon {
  width: 36px;
  height: 36px;
  padding: 0;
  border-radius: var(--radius-sm);
  font-size: 1rem;
  flex-shrink: 0;
}
.btn-new-chat {
  width: 100%;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.625rem;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 600;
  background: var(--primary);
  color: var(--primary-fg);
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  transition: all var(--transition);
}
.btn-new-chat:hover { background: var(--primary-hover); transform: translateY(-1px); }
.btn-new-chat:active { transform: translateY(0); }
.btn-sidebar-link {
  width: 100%;
  justify-content: flex-start;
  gap: 0.5rem;
  padding: 0.5rem 0.75rem;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  color: var(--text-muted);
  transition: all var(--transition);
}
.btn-sidebar-link:hover { background: var(--surface-2); color: var(--text); }

/* ── Select ──────────────────────────────────────────────────── */
.model-select {
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 5px 10px;
  font-size: 0.8rem;
  color: var(--text);
  max-width: 220px;
  cursor: pointer;
  font-weight: 500;
}

/* ── Settings Drawer ─────────────────────────────────────────── */
.drawer-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  z-index: 40;
  animation: fadeIn 0.15s ease;
}
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
.drawer-overlay.open { display: flex; align-items: center; justify-content: center; }
.drawer {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 1.5rem;
  width: 420px;
  max-width: 95vw;
  display: flex;
  flex-direction: column;
  gap: 1.125rem;
  box-shadow: var(--shadow-lg);
  animation: slideUp 0.2s ease-out;
}
@keyframes slideUp {
  from { opacity: 0; transform: translateY(12px) scale(0.98); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}
.drawer h3 { font-size: 1.05rem; font-weight: 600; }
.drawer label {
  font-size: 0.8rem;
  color: var(--text-muted);
  display: block;
  margin-bottom: 5px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
.drawer textarea {
  width: 100%;
  padding: 0.625rem 0.75rem;
  min-height: 90px;
  resize: vertical;
  line-height: 1.5;
}
.range-row { display: flex; align-items: center; gap: 0.75rem; }
.range-row span { font-size: 0.8rem; min-width: 20px; color: var(--text-muted); }
input[type=range] {
  accent-color: var(--primary);
  background: none;
  border: none;
  width: 100%;
  padding: 0;
}
input[type=range]:focus { box-shadow: none; }

/* ── Login Page ──────────────────────────────────────────────── */
.login-page {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  background: radial-gradient(ellipse at center top, var(--primary-soft) 0%, transparent 60%);
}
.login-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 2.5rem 2rem;
  width: 100%;
  max-width: 380px;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  box-shadow: var(--shadow-lg);
}
.login-card h1 { font-size: 1.5rem; font-weight: 700; text-align: center; letter-spacing: -0.02em; }
.login-card p { font-size: 0.875rem; color: var(--text-muted); text-align: center; }
.login-card input[type=password] { width: 100%; padding: 0.75rem 1rem; font-size: 0.925rem; }
.login-card .btn-primary { padding: 0.75rem; font-size: 0.925rem; }
.error-msg {
  font-size: 0.825rem;
  color: var(--danger);
  text-align: center;
  min-height: 1.2em;
}

/* ── Admin Panel ─────────────────────────────────────────────── */
.admin-layout {
  max-width: 960px;
  margin: 2rem auto;
  padding: 0 1rem;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}
.admin-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.admin-header h1 { font-size: 1.5rem; font-weight: 700; letter-spacing: -0.02em; }
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}
.card-header {
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.card-header h2 { font-size: 1rem; font-weight: 600; }
.card-body { padding: 1.25rem; }
.card-body input[type=text], .card-body input[type=url], .card-body input[type=password] {
  padding: 0.625rem 0.75rem;
  font-size: 0.9rem;
}
table { width: 100%; border-collapse: collapse; font-size: 0.875rem; }
th {
  text-align: left;
  padding: 0.625rem 1rem;
  color: var(--text-muted);
  font-weight: 500;
  border-bottom: 1px solid var(--border);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
td { padding: 0.75rem 1rem; border-bottom: 1px solid var(--border-light); color: var(--text); }
tr:last-child td { border-bottom: none; }
tr:hover td { background: var(--surface-2); }
.badge {
  display: inline-flex;
  padding: 2px 10px;
  border-radius: 99px;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.01em;
}
.badge-green { background: var(--success-soft); color: var(--success); }
.badge-red { background: var(--danger-soft); color: var(--danger); }
.badge-purple { background: var(--primary-soft); color: var(--primary); }
.key-mono { font-family: var(--font-mono); font-size: 0.8rem; color: var(--text-muted); }

/* ── Empty State ─────────────────────────────────────────────── */
.empty-state {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  color: var(--text-muted);
  text-align: center;
  padding: 2rem;
}
.empty-state-icon { font-size: 3rem; opacity: 0.4; }
.empty-state h3 { font-size: 1.15rem; font-weight: 600; color: var(--text); }
.empty-state p { font-size: 0.875rem; max-width: 320px; line-height: 1.5; }

/* ── Responsive ──────────────────────────────────────────────── */
@media (max-width: 640px) {
  .sidebar { width: 200px; }
  :root { --sidebar-width: 200px; }
  .model-select { max-width: 120px; }
  .admin-layout { margin: 1rem auto; }
}
@media (max-width: 480px) {
  .sidebar { display: none; }
  .messages-area { padding: 1rem 0.75rem; }
  .card-body { padding: 1rem; }
  th, td { padding: 0.5rem 0.625rem; }
}