*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:                      #ffffff;
  --surface:                 #f8f9fb;
  --surface2:                #f0f2f5;
  --border:                  #e2e5eb;
  --accent:                  #2563eb;
  --accent2:                 #7c3aed;
  --text:                    #1a1d23;
  --muted:                   #8a93a8;
  --muted-accessible:        #6b7280;
  --user-bg:                 #eff6ff;
  --user-border:             #bfdbfe;
  --bot-bg:                  #f3f4f6;
  --bot-border:              #e5e7eb;
  --success:                 #16a34a;
  --error:                   #e55;
  --radius:                  12px;
  --font-ui:                 'Syne', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono:               'JetBrains Mono', 'Fira Code', 'Cascadia Code', monospace;
  --sidebar-width:           180px;
  --sidebar-collapsed-width: 56px;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-ui);
  min-height: 100vh;
  overflow-x: hidden;
}

::-webkit-scrollbar { width: 4px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 4px; }

.app { display: flex; height: 100vh; }

/* ── Sidebar ── */
.sidebar {
  width: var(--sidebar-width);
  min-width: var(--sidebar-collapsed-width);
  background: var(--surface);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  padding: 12px 14px 20px;
  gap: 6px;
  transition: width 0.25s ease;
  overflow: hidden;
}

.sidebar.collapsed {
  width: var(--sidebar-collapsed-width);
  padding-left: 8px;
  padding-right: 8px;
}

/* ── Sidebar header (toggle row) ── */
.sidebar-header {
  display: flex;
  justify-content: flex-end;
  margin-bottom: 10px;
}

.sidebar.collapsed .sidebar-header {
  justify-content: center;
}

.sidebar-toggle {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: none;
  cursor: pointer;
  font-size: 20px;
  color: var(--muted);
  line-height: 1;
  padding: 4px 6px;
  border-radius: 6px;
  transition: background 0.15s, color 0.15s;
}

.sidebar-toggle:hover {
  background: var(--surface2);
  color: var(--text);
}

/* ── Shared sidebar button style ── */
.sidebar-btn {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  font-weight: 700;
  padding: 10px 14px;
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.15s;
  user-select: none;
  text-decoration: none;
  width: 100%;
  position: relative;
}

.sidebar-btn-accent {
  color: var(--accent);
  background: color-mix(in srgb, var(--accent) 8%, transparent);
  border: 1px solid color-mix(in srgb, var(--accent) 20%, transparent);
}

.sidebar-btn-accent:hover {
  background: #e8e8e8;
  border-color: #aaaaaa;
}

.sidebar-btn-muted {
  color: var(--text);
  background: transparent;
  border: 1px solid var(--muted);
}

.sidebar-btn-muted:hover {
  background: color-mix(in srgb, var(--muted) 10%, transparent);
  border-color: var(--muted);
  color: var(--text);
}

.sidebar-btn-active {
  color: var(--bg);
  background: var(--text);
  border: 1px solid var(--text);
  font-weight: 600;
}

.sidebar-btn-active:hover {
  background: color-mix(in srgb, var(--text) 80%, transparent);
  border-color: color-mix(in srgb, var(--text) 80%, transparent);
  color: var(--bg);
}

/* ── Button text/icon collapse behaviour ── */
.btn-text {
  transition: opacity 0.2s ease;
}

.sidebar.collapsed .btn-text {
  display: none;
}

.sidebar.collapsed .sidebar-btn {
  justify-content: center;
  padding: 10px;
  width: auto;
  height: 40px;
  margin: 4px auto;
  border-radius: 8px;
}

/* ── Tooltips ── */
.btn-tooltip {
  display: none;
  position: fixed;
  left: calc(var(--sidebar-collapsed-width) + 8px);
  background: var(--text);
  color: var(--bg);
  font-size: 12px;
  font-weight: 600;
  padding: 5px 10px;
  border-radius: 6px;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.15s ease;
  z-index: 1000;
}

/* Sidebar button tooltips — only visible when collapsed */
.sidebar.collapsed .sidebar-btn .btn-tooltip {
  display: block;
}

.sidebar.collapsed .sidebar-btn:hover .btn-tooltip {
  opacity: 1;
}

/* Toggle button tooltip — always visible on hover regardless of state */
.sidebar-toggle .btn-tooltip {
  display: block;
}

.sidebar-toggle:hover .btn-tooltip {
  opacity: 1;
}

/* ── Sidebar footer ── */
.sidebar-footer {
  margin-top: auto;
  padding-top: 14px;
  font-size: 11px;
  color: var(--muted);
  font-family: var(--font-mono);
  padding-left: 4px;
  line-height: 1.8;
}

.sidebar.collapsed #user-id {
  display: none;
}

/* ── Status dot ── */
.status-dot {
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--success);
  margin-right: 6px;
  box-shadow: 0 0 5px var(--success);
}

.status-dot--error {
  background: var(--error);
  box-shadow: 0 0 5px var(--error);
}

/* ── New chat button ── */
.new-chat-btn {
  display: flex;
  font-size: 14px;
  font-weight: 700;
  padding: 10px 14px;
  border-radius: var(--radius);
  cursor: pointer;
  color: var(--accent);
  background: color-mix(in srgb, var(--accent) 8%, transparent);
  border: 1px solid color-mix(in srgb, var(--accent) 20%, transparent);
  transition: all 0.15s;
  user-select: none;
}

.new-chat-btn:hover {
  background: color-mix(in srgb, var(--accent) 14%, transparent);
  border-color: color-mix(in srgb, var(--accent) 35%, transparent);
  transform: scale(1.08);
}

/* ── Main ── */
.main { flex: 1; display: flex; flex-direction: column; overflow: hidden; }

.topbar {
  height: 56px;
  min-height: 56px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  padding: 0 28px;
  background: var(--bg);
  justify-content: space-between;
}

.topbar-title { font-size: 15px; font-weight: 700; color: var(--text); }

.topbar-user {
  display: flex;
  align-items: center;
}

#user-id {
  font-size: 0.8em;
  opacity: 0.7;
  text-align: right;
}

/* ── Chat ── */
.chat-view { flex: 1; display: flex; flex-direction: column; overflow: hidden; background: var(--bg); }

.messages {
  flex: 1;
  overflow-y: auto;
  padding: 28px 40px;
  display: flex;
  flex-direction: column;
  gap: 18px;
}

/* ── Messages ── */
.msg { display: flex; gap: 12px; animation: fadeUp 0.2s ease; max-width: 820px; }
.msg.user { align-self: flex-end; flex-direction: row-reverse; }
.msg.bot  { align-self: flex-start; }

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}

.avatar {
  width: 32px; height: 32px; min-width: 32px;
  border-radius: 9px;
  display: flex; align-items: center; justify-content: center;
  font-size: 14px; font-weight: 800;
}

.avatar.user { background: var(--accent2); color: #fff; }
.avatar.bot {
  background: color-mix(in srgb, var(--accent) 10%, white);
  color: var(--accent);
  border: 1px solid color-mix(in srgb, var(--accent) 20%, transparent);
  font-size: 17px;
}

.bubble {
  padding: 12px 16px;
  border-radius: var(--radius);
  font-size: 16px;
  line-height: 1.5;
  max-width: 680px;
}

.msg.user .bubble {
  background: var(--user-bg);
  border: 1px solid var(--user-border);
  border-top-right-radius: 2px;
  color: var(--text);
}

.msg.bot .bubble {
  background: var(--bot-bg);
  border: 1px solid var(--bot-border);
  border-top-left-radius: 2px;
  color: var(--text);
}

.bubble-time { font-size: 10px; color: var(--muted); font-family: var(--font-mono); margin-top: 5px; }
.msg.user .bubble-time { text-align: right; }

/* Markdown */
.bubble p { margin-bottom: 8px; }
.bubble p:last-child { margin-bottom: 0; }
.bubble ul, .bubble ol { padding-left: 20px; margin-bottom: 8px; }
.bubble li { margin-bottom: 3px; }
.bubble h1, .bubble h2, .bubble h3 { font-size: 14px; font-weight: 700; margin: 10px 0 5px; color: var(--accent); }
.bubble code { font-family: var(--font-mono); font-size: 12px; background: rgba(0,0,0,0.06); padding: 2px 5px; border-radius: 4px; }
.bubble pre { background: var(--surface2); border: 1px solid var(--border); border-radius: 8px; padding: 12px; overflow-x: auto; margin: 8px 0; }
.bubble pre code { background: none; padding: 0; }

/* ── Typing ── */
.typing { display: flex; align-items: center; gap: 4px; padding: 4px 0; }
.typing span { width: 6px; height: 6px; border-radius: 50%; background: var(--muted); animation: bounce 1.2s infinite; }
.typing span:nth-child(2) { animation-delay: 0.2s; }
.typing span:nth-child(3) { animation-delay: 0.4s; }

@keyframes bounce {
  0%, 60%, 100% { transform: translateY(0); opacity: 0.4; }
  30% { transform: translateY(-6px); opacity: 1; }
}

/* ── Input bar ── */
.input-bar {
  padding: 16px 40px;
  background: var(--bg);
  display: flex;
  gap: 10px;
  align-items: center;
}

.input-wrap { flex: 1; }

.chat-input {
  width: 100%;
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-family: var(--font-ui);
  font-size: 16px;
  padding: 12px 16px;
  resize: none;
  outline: none;
  transition: border-color 0.15s, box-shadow 0.15s;
  min-height: 46px;
  max-height: 140px;
  overflow-y: auto;
  box-sizing: border-box;
}

.chat-input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 12%, transparent);
}

.chat-input::placeholder { color: var(--muted); }

.chat-input:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  background: var(--surface2);
}

.send-btn {
  width: 46px; height: 46px; min-width: 46px;
  border-radius: var(--radius); border: none; cursor: pointer;
  background: var(--accent); color: #fff;
  font-size: 18px; font-weight: 800;
  display: flex; align-items: center; justify-content: center;
  transition: all 0.15s;
}

.send-btn:hover { background: color-mix(in srgb, var(--accent) 85%, black); transform: scale(1.04); }
.send-btn:disabled { opacity: 0.3; cursor: not-allowed; transform: none; }

/* ── Welcome ── */
.welcome {
  flex: 1; display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  gap: 10px; padding: 40px; text-align: center;
}

.welcome-icon { font-size: 44px; margin-bottom: 6px; }
.welcome h2 { font-size: 26px; font-weight: 800; color: var(--text); }
.welcome h2 span { color: var(--accent); }
.welcome p { color: var(--muted-accessible); font-size: 14px; max-width: 360px; line-height: 1.6; }

.suggestion-chips { display: flex; flex-wrap: wrap; gap: 8px; justify-content: center; margin-top: 16px; }

.chip {
  padding: 8px 16px;
  border-radius: 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  font-size: 14px;
  cursor: pointer;
  color: var(--text);
  transition: all 0.15s;
}

.chip:hover { border-color: var(--accent); color: var(--accent); background: color-mix(in srgb, var(--accent) 6%, white); }

/* ── Chat wrapper ── */
.chat-wrapper {
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  height: 100vh;
  overflow: hidden;
  z-index: 1;
}

.chat-wrapper .app { height: 100%; }
.chat-wrapper .msg { padding: 0; background: none; }
.chat-wrapper .main { min-width: 0; }
.chat-wrapper .sidebar { padding-left: 14px; padding-right: 14px; }

.messages .msg {
  padding: 0 !important;
  background: #ffffff !important;
  background-color: #ffffff !important;
}

/* ── Disclaimer ── */
.disclaimer-bar {
  text-align: center;
  font-size: 11px;
  color: var(--muted-accessible);
  font-family: var(--font-mono);
  padding: 0 40px 18px;
  background: var(--bg);
}

/* ── Misc ── */
.signin-prompt {
  margin: 12px 0;
  display: flex;
  justify-content: center;
}

.chat-logo {
  height: 80px;
  width: auto;
  opacity: 0.75;
  transition: opacity 0.3s;
}

.chat-logo:hover { opacity: 1.0; }

.chip-rate-limit {
  font-size: 0.8em;
  opacity: 0.7;
  color: var(--warning);
  padding: 8px 12px;
}

/* ── Responsive ── */
@media (max-width: 768px) {
  .sidebar { width: var(--sidebar-collapsed-width); }
  .btn-text { display: none; }
  .sidebar-btn { justify-content: center; }
  .sidebar-toggle { display: none; }
}

@media (max-width: 700px) {
  .messages { padding: 16px; }
  .input-bar { padding: 12px 16px; }
}