/* ============================================================
   VamusAI — warm editorial theme
   Cream canvas, a serif display face for personality, and one
   signature clay accent. The agent step-trace keeps its four
   functional colors as the one place color is allowed to work.
   ============================================================ */

:root {
  --bg: #faf8f4;
  --sidebar-bg: #f2efe8;
  --surface: #ffffff;
  --surface-2: #f0ede5;
  --surface-3: #e8e4d9;
  --border: #e6e1d4;
  --border-strong: #d8d2c0;

  --text: #24211b;
  --text-muted: #6f6a5c;
  --text-faint: #a39c88;

  --ink: #24211b;          /* primary buttons */
  --ink-hover: #3a362c;

  --accent: #b1552f;       /* signature clay accent — used sparingly */
  --accent-hover: #9a4726;
  --accent-soft: #f7e9df;

  --think: #c17a2e;
  --design: #7c5cd6;
  --code: #157f74;
  --review: #4c8c53;

  --think-soft: #fbf0e1;
  --danger: #b4432c;
  --danger-soft: #fbeee9;

  --font-display: "Fraunces", "Iowan Old Style", Georgia, serif;
  --font-body: "Inter", "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", "SFMono-Regular", Consolas, monospace;

  --sidebar-w: 272px;

  --shadow-sm: 0 1px 2px rgba(36, 33, 27, 0.06);
  --shadow-md: 0 2px 10px rgba(36, 33, 27, 0.08);
  --shadow-lg: 0 18px 50px rgba(36, 33, 27, 0.16);

  --radius: 12px;
  --radius-lg: 16px;
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.001ms !important; transition-duration: 0.001ms !important; }
}

* { box-sizing: border-box; }

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

body { overflow: hidden; }

button, textarea { font-family: inherit; }

:focus-visible { outline: 2px solid var(--ink); outline-offset: 2px; border-radius: 4px; }

/* ---------- app shell ---------- */
.app {
  display: grid;
  grid-template-columns: var(--sidebar-w) 1fr;
  height: 100vh;
  transition: grid-template-columns 0.2s ease;
}
.app.sidebar-collapsed {
  grid-template-columns: 0 1fr;
}

/* ---------- sidebar ---------- */
.sidebar {
  background: var(--sidebar-bg);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  padding: 0.85rem 0.85rem 1rem;
  overflow: hidden;
  min-width: 0;
}

.app.sidebar-collapsed .sidebar {
  padding-left: 0;
  padding-right: 0;
  border-right-color: transparent;
}

.sidebar-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.3rem 0.3rem 0.7rem 0.55rem;
}

.sidebar-topbar-icons {
  display: flex;
  align-items: center;
  gap: 0.15rem;
}

.icon-btn {
  width: 28px;
  height: 28px;
  border-radius: 7px;
  border: none;
  background: none;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 0.12s ease, color 0.12s ease;
}
.icon-btn:hover { background: var(--surface-3); color: var(--text); }

.sidebar-expand-btn {
  position: fixed;
  top: 0.9rem;
  left: 1rem;
  z-index: 15;
  width: 30px;
  height: 30px;
  border-radius: 7px;
  border: 1px solid var(--border);
  background: #ffffff;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
}
.sidebar-expand-btn:hover { color: var(--text); }
.sidebar-expand-btn[hidden] { display: none; }

.sidebar-search {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 9px;
  padding: 0.45rem 0.6rem;
  margin: 0 0.05rem 0.7rem;
  color: var(--text-faint);
}
.sidebar-search[hidden] { display: none; }
.sidebar-search input {
  border: none;
  background: none;
  outline: none;
  font-size: 0.82rem;
  color: var(--text);
  width: 100%;
}
.sidebar-search input::placeholder { color: var(--text-faint); }

.sidebar-top { margin-bottom: 1.2rem; }

.brand {
  font-family: var(--font-display);
  font-weight: 600;
  font-style: italic;
  font-size: 1.2rem;
  letter-spacing: -0.01em;
  color: var(--text);
}

.chat-list-item.is-search-hidden { display: none; }

.new-chat-btn {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--ink);
  border: none;
  color: #ffffff;
  border-radius: 10px;
  padding: 0.65rem 0.85rem;
  font-size: 0.86rem;
  font-weight: 500;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: background 0.15s ease, transform 0.1s ease;
}
.new-chat-btn:hover { background: var(--ink-hover); }
.new-chat-btn:active { transform: scale(0.99); }
.new-chat-btn span { font-size: 1.05rem; line-height: 1; font-weight: 400; }

.sidebar-section-label {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-faint);
  padding: 0.4rem 0.55rem 0.5rem;
}

.chat-list {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
}

.chat-list-item {
  text-align: left;
  background: none;
  border: none;
  color: var(--text-muted);
  padding: 0.55rem 0.6rem;
  border-radius: 8px;
  font-size: 0.85rem;
  cursor: pointer;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: background 0.12s ease, color 0.12s ease;
}
.chat-list-item:hover { background: var(--surface-3); color: var(--text); }
.chat-list-item.active { background: #ffffff; color: var(--text); box-shadow: var(--shadow-sm); font-weight: 500; }

.chat-list-empty {
  color: var(--text-faint);
  font-size: 0.8rem;
  padding: 0.6rem;
}

.sidebar-bottom {
  border-top: 1px solid var(--border);
  padding-top: 0.85rem;
  margin-top: 0.6rem;
}

.agent-key {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.35rem 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--text-muted);
  padding: 0 0.35rem;
}

.dot { width: 7px; height: 7px; border-radius: 50%; display: inline-block; margin-right: 0.2rem; }
.dot-think { background: var(--think); }
.dot-design { background: var(--design); }
.dot-code { background: var(--code); }
.dot-review { background: var(--review); }

.settings-btn {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: none;
  border: none;
  color: var(--text-muted);
  padding: 0.55rem 0.5rem;
  border-radius: 8px;
  font-size: 0.85rem;
  cursor: pointer;
  margin-top: 0.55rem;
  transition: background 0.12s ease, color 0.12s ease;
}
.settings-btn:hover { background: var(--surface-3); color: var(--text); }
.settings-btn svg { flex-shrink: 0; }

/* ---------- main column ---------- */
.main {
  display: flex;
  flex-direction: column;
  height: 100vh;
  min-width: 0;
  background: var(--bg);
}

.thread {
  flex: 1;
  overflow-y: auto;
  padding: 2.5rem 1.5rem 1rem;
}

.empty-state {
  max-width: 560px;
  margin: 16vh auto 0;
  text-align: center;
}
.empty-state h1 {
  font-family: var(--font-display);
  font-size: 2.6rem;
  font-weight: 600;
  font-style: italic;
  letter-spacing: -0.015em;
  margin: 0 0 0.85rem;
  color: var(--text);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
}
.empty-state h1 span[aria-hidden="true"] {
  font-style: normal;
  color: var(--accent);
  font-size: 0.85em;
}
.empty-state p {
  color: var(--text-muted);
  font-size: 1rem;
  line-height: 1.7;
  margin: 0;
  max-width: 460px;
  margin-left: auto;
  margin-right: auto;
}

/* ---------- messages ---------- */
.msg {
  max-width: 740px;
  margin: 0 auto 2.25rem;
}

.msg-user { display: flex; justify-content: flex-end; margin-bottom: 1.15rem; }
.msg-user-bubble {
  background: var(--surface-2);
  border-radius: 18px 18px 6px 18px;
  padding: 0.7rem 1.05rem;
  max-width: 80%;
  font-size: 0.94rem;
  line-height: 1.55;
  white-space: pre-wrap;
}

.msg-assistant { font-size: 0.96rem; line-height: 1.7; color: var(--text); }

.stream-live {
  white-space: pre-wrap;
}
.stream-live::after {
  content: "▍";
  display: inline-block;
  color: var(--think);
  animation: blink 1s step-start infinite;
  margin-left: 1px;
}
@keyframes blink { 50% { opacity: 0; } }

/* ---------- routing indicator ---------- */
.routing-indicator {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  color: var(--text-muted);
  font-size: 0.86rem;
  padding: 0.3rem 0.1rem;
  margin-bottom: 0.4rem;
}
.routing-indicator::before {
  content: "";
  width: 13px;
  height: 13px;
  border-radius: 50%;
  border: 2px solid var(--border-strong);
  border-top-color: var(--think);
  flex-shrink: 0;
  animation: spin 0.7s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* ---------- steps (agent trace — the signature element) ---------- */
.steps {
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
  margin-bottom: 1rem;
  padding: 0.35rem;
  background: var(--sidebar-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.steps[hidden] { display: none; }

.step { border-radius: 8px; }

.step-toggle {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  background: none;
  border: none;
  color: var(--text-muted);
  padding: 0.45rem 0.55rem;
  border-radius: 8px;
  cursor: pointer;
  width: 100%;
  text-align: left;
  font-size: 0.85rem;
  transition: background 0.12s ease, color 0.12s ease;
}
.step-toggle:hover { background: var(--surface-3); color: var(--text); }

.step-spinner {
  width: 13px;
  height: 13px;
  border-radius: 50%;
  border: 2px solid var(--border-strong);
  border-top-color: var(--think);
  flex-shrink: 0;
  display: none;
  animation: spin 0.7s linear infinite;
}

.step-check {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
  display: none;
  align-items: center;
  justify-content: center;
  font-size: 0.6rem;
  font-weight: 700;
  border-radius: 50%;
  color: #ffffff;
}

.step[data-state="running"] .step-spinner { display: inline-block; }
.step[data-state="running"] .step-label { color: var(--text); font-weight: 500; }

.step[data-state="done"] .step-check { display: inline-flex; }
.step[data-state="error"] .step-check {
  display: inline-flex;
  background: var(--danger);
  font-size: 0;
}
.step[data-state="error"] .step-check::before { content: "!"; font-size: 0.6rem; }

.step-check.c-think { background: var(--think); }
.step-check.c-design { background: var(--design); }
.step-check.c-code { background: var(--code); }
.step-check.c-review { background: var(--review); }

.step-label {
  flex: 1;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.01em;
}

.step-chevron {
  color: var(--text-faint);
  transition: transform 0.15s ease;
  flex-shrink: 0;
}
.step.is-open .step-chevron { transform: rotate(180deg); }

.step-body {
  margin: 0.25rem 0.45rem 0.55rem 2rem;
  padding: 0.8rem 1rem;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 10px;
  font-size: 0.86rem;
  line-height: 1.6;
  color: var(--text-muted);
  max-height: 340px;
  overflow-y: auto;
  box-shadow: var(--shadow-sm);
}

/* ---------- final answer ---------- */
.answer { color: var(--text); }
.answer p { margin: 0 0 0.9rem; }
.answer ul, .answer ol { margin: 0 0 0.9rem; padding-left: 1.35rem; }
.answer li { margin-bottom: 0.35rem; }
.answer h3, .answer h4 {
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--text);
  margin: 1.4rem 0 0.55rem;
}
.answer strong { font-weight: 600; }
.answer code {
  font-family: var(--font-mono);
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 5px;
  padding: 0.1rem 0.4rem;
  font-size: 0.84em;
}
.answer .code-file {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  color: var(--text-muted);
  margin: 1.1rem 0 0.4rem;
}
.answer pre {
  background: #fbfbfa;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem 1.1rem;
  overflow-x: auto;
  margin: 0 0 0.9rem;
  box-shadow: var(--shadow-sm);
}
.answer pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: 0.82rem;
  line-height: 1.6;
  color: var(--text);
}

.answer-actions { margin-top: 0.6rem; }
.copy-btn {
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-muted);
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.42rem 0.85rem;
  cursor: pointer;
  transition: color 0.12s ease, border-color 0.12s ease, box-shadow 0.12s ease;
}
.copy-btn:hover { color: var(--text); border-color: var(--border-strong); box-shadow: var(--shadow-sm); }

.error-msg {
  color: var(--danger);
  font-size: 0.86rem;
  margin: 0 0 0.55rem;
}
.retry-btn {
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--danger);
  background: var(--danger-soft);
  border: 1px solid transparent;
  border-radius: 8px;
  padding: 0.42rem 0.85rem;
  cursor: pointer;
  transition: border-color 0.12s ease;
}
.retry-btn:hover { border-color: var(--danger); }

/* ---------- composer ---------- */
.composer-wrap {
  padding: 0.5rem 1.5rem 1.4rem;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0), var(--bg) 45%);
}

.composer {
  max-width: 740px;
  margin: 0 auto;
  display: flex;
  align-items: flex-end;
  gap: 0.4rem;
  background: #ffffff;
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 0.55rem 0.65rem 0.55rem 0.55rem;
  box-shadow: var(--shadow-md);
  transition: box-shadow 0.15s ease, border-color 0.15s ease;
}
.composer:focus-within {
  border-color: var(--ink);
  box-shadow: 0 4px 16px rgba(36, 33, 27, 0.12);
}

.composer-input {
  flex: 1;
  resize: none;
  background: none;
  border: none;
  color: var(--text);
  font-size: 0.95rem;
  line-height: 1.55;
  padding: 0.42rem 0;
  max-height: 200px;
}
.composer-input::placeholder { color: var(--text-faint); }
.composer-input:focus { outline: none; }

.send-btn {
  flex-shrink: 0;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  border: none;
  background: var(--ink);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 0.15s ease, transform 0.1s ease, opacity 0.15s ease;
}
.send-btn:hover:not(:disabled) { background: var(--ink-hover); transform: translateY(-1px); }
.send-btn:disabled { opacity: 0.35; cursor: default; }

/* ---------- inline model picker (composer) ---------- */
.model-picker {
  position: relative;
  flex-shrink: 0;
}

.model-picker-btn {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  background: var(--surface-2);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 999px;
  padding: 0.4rem 0.5rem 0.4rem 0.7rem;
  font-size: 0.78rem;
  font-weight: 500;
  cursor: pointer;
  white-space: nowrap;
  transition: background 0.12s ease, border-color 0.12s ease;
}
.model-picker-btn:hover { border-color: var(--border-strong); background: var(--surface-3); }
.model-picker-btn svg { flex-shrink: 0; transition: transform 0.15s ease; opacity: 0.6; }
.model-picker.is-open .model-picker-btn svg { transform: rotate(180deg); }

.model-picker-btn-effort {
  color: var(--text-faint);
  font-weight: 500;
  padding-left: 0.4rem;
  border-left: 1px solid var(--border-strong);
}

.model-picker-menu {
  position: absolute;
  bottom: calc(100% + 0.5rem);
  right: 0;
  width: 260px;
  background: #ffffff;
  border: 1px solid var(--border-strong);
  border-radius: 14px;
  box-shadow: var(--shadow-lg);
  padding: 0.4rem;
  z-index: 20;
  overflow: hidden;
}
.model-picker-menu[hidden] { display: none; }

.model-picker-panel[hidden] { display: none; }

.model-picker-option {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  background: none;
  border: none;
  border-radius: 8px;
  padding: 0.55rem 0.6rem;
  text-align: left;
  cursor: pointer;
  transition: background 0.12s ease;
}
.model-picker-option:hover:not(.is-disabled) { background: var(--surface-2); }
.model-picker-option.is-disabled { opacity: 0.4; cursor: not-allowed; }

.model-picker-option-text {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.05rem;
  min-width: 0;
}
.model-picker-option-name {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 0.4rem;
}
.model-picker-option-sub {
  font-size: 0.72rem;
  color: var(--text-faint);
}
.model-picker-option-badge {
  font-size: 0.62rem;
  font-weight: 600;
  color: var(--text-faint);
  background: var(--surface-3);
  border-radius: 5px;
  padding: 0.1rem 0.35rem;
  text-transform: none;
}

.model-picker-check {
  flex-shrink: 0;
  color: var(--accent);
  opacity: 0;
}
.model-picker-option.is-selected .model-picker-check { opacity: 1; }

.model-picker-divider {
  height: 1px;
  background: var(--border);
  margin: 0.35rem 0.4rem;
}

.model-picker-row {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: none;
  border: none;
  border-radius: 8px;
  padding: 0.55rem 0.6rem;
  cursor: pointer;
  transition: background 0.12s ease;
}
.model-picker-row:hover { background: var(--surface-2); }
.model-picker-row-label { font-size: 0.85rem; font-weight: 500; color: var(--text); }
.model-picker-row-value {
  display: flex;
  align-items: center;
  gap: 0.3rem;
  font-size: 0.8rem;
  color: var(--text-faint);
}
.model-picker-row-value svg { opacity: 0.6; }

.model-picker-back {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  background: none;
  border: none;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text);
  padding: 0.5rem 0.55rem 0.4rem;
  cursor: pointer;
}
.model-picker-back:hover { color: var(--accent); }

.model-picker-effort-desc {
  font-size: 0.74rem;
  line-height: 1.5;
  color: var(--text-faint);
  padding: 0 0.6rem 0.5rem;
}

.composer-hint {
  max-width: 740px;
  margin: 0.6rem auto 0;
  text-align: center;
  font-size: 0.72rem;
  color: var(--text-faint);
}

.suggestion-chips {
  max-width: 740px;
  margin: 0.9rem auto 0;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.5rem;
}
.suggestion-chips[hidden] { display: none; }

.suggestion-chip {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.5rem 0.9rem;
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-muted);
  cursor: pointer;
  transition: border-color 0.12s ease, color 0.12s ease, box-shadow 0.12s ease;
}
.suggestion-chip:hover {
  border-color: var(--border-strong);
  color: var(--text);
  box-shadow: var(--shadow-sm);
}
.suggestion-chip svg { flex-shrink: 0; opacity: 0.75; }

/* ---------- settings ---------- */
.settings-overlay {
  position: fixed;
  inset: 0;
  background: rgba(28, 30, 33, 0.32);
  backdrop-filter: blur(2px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 50;
  padding: 1.5rem;
}
.settings-overlay[hidden] { display: none; }

.settings-panel {
  width: 100%;
  max-width: 500px;
  max-height: 85vh;
  overflow-y: auto;
  background: #ffffff;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
}

.settings-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.15rem 1.4rem;
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  background: #ffffff;
  z-index: 1;
}
.settings-header h2 {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin: 0;
}
.settings-close {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 0.9rem;
  cursor: pointer;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.12s ease, color 0.12s ease;
}
.settings-close:hover { background: var(--surface-2); color: var(--text); }

.settings-body { padding: 1.3rem 1.4rem 1.6rem; }

.settings-section + .settings-section {
  margin-top: 1.7rem;
  padding-top: 1.7rem;
  border-top: 1px solid var(--border);
}

.settings-section h3 {
  font-family: var(--font-display);
  font-size: 0.94rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  margin: 0 0 0.35rem;
}
.settings-desc {
  color: var(--text-muted);
  font-size: 0.85rem;
  line-height: 1.55;
  margin: 0 0 1rem;
}

.effort-options {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(84px, 1fr));
  gap: 0.5rem;
}

.effort-btn {
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.7rem 0.5rem;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.2rem;
  text-align: center;
  transition: border-color 0.12s ease, background 0.12s ease, box-shadow 0.12s ease;
}
.effort-btn:hover { border-color: var(--border-strong); box-shadow: var(--shadow-sm); }
.effort-btn.is-active {
  border-color: var(--ink);
  background: var(--surface-2);
  box-shadow: inset 0 0 0 1px var(--ink);
}
.effort-name {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text);
}
.effort-sub {
  font-size: 0.68rem;
  color: var(--text-faint);
  line-height: 1.3;
}

.model-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}
.model-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.75rem 1rem;
  cursor: pointer;
  transition: border-color 0.12s ease, box-shadow 0.12s ease;
}
.model-row:hover:not(.is-disabled) { border-color: var(--border-strong); box-shadow: var(--shadow-sm); }
.model-row:has(input:checked) {
  border-color: var(--ink);
  box-shadow: inset 0 0 0 1px var(--ink);
}
.model-row.is-disabled { opacity: 0.45; cursor: not-allowed; }
.model-name { font-size: 0.89rem; font-weight: 500; }
.model-sub { font-size: 0.75rem; color: var(--text-faint); margin-top: 0.18rem; }
.model-row input[type="radio"] { accent-color: var(--ink); width: 16px; height: 16px; flex-shrink: 0; }

/* ---------- responsive ---------- */
@media (max-width: 820px) {
  .app { grid-template-columns: 1fr; }
  .sidebar { display: none; }
  .thread { padding: 1.5rem 1rem 1rem; }
  .composer-wrap { padding: 0.5rem 1rem 1.1rem; }
  .empty-state { margin-top: 10vh; }
  .model-picker-btn { padding: 0.4rem 0.45rem 0.4rem 0.55rem; font-size: 0.72rem; }
  .model-picker-btn span[data-role="modelPickerLabel"] { max-width: 52px; overflow: hidden; display: inline-block; text-overflow: ellipsis; white-space: nowrap; }
  .model-picker-btn-effort { display: none; }
  .model-picker-menu { width: 230px; }
}

/* ---------- toast notifications ---------- */
.toast-container {
  position: fixed;
  bottom: 1.5rem;
  left: 50%;
  transform: translateX(-50%);
  z-index: 100;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  pointer-events: none;
}

.toast {
  background: var(--ink);
  color: #ffffff;
  font-size: 0.84rem;
  font-weight: 500;
  padding: 0.65rem 1.1rem;
  border-radius: 999px;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.25s ease, transform 0.25s ease;
  white-space: nowrap;
}

.toast.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ---------- file attachments ---------- */
.attach-btn {
  flex-shrink: 0;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  border: none;
  background: none;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 0.12s ease, color 0.12s ease;
}
.attach-btn:hover { background: var(--surface-2); color: var(--text); }

.file-tray {
  max-width: 740px;
  margin: 0 auto 0.6rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}
.file-tray[hidden] { display: none; }

.file-chip {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  background: #ffffff;
  border: 1px solid var(--border-strong);
  border-radius: 10px;
  padding: 0.4rem 0.55rem;
  box-shadow: var(--shadow-sm);
  max-width: 220px;
}

.file-msg-chip {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.4rem 0.6rem;
  max-width: 240px;
  margin-bottom: 0.4rem;
}

.file-chip-icon {
  flex-shrink: 0;
  width: 32px;
  height: 32px;
  border-radius: 7px;
  background: var(--surface-2);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.68rem;
  font-weight: 700;
  color: var(--text-muted);
  overflow: hidden;
}
.file-chip-icon img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.file-chip-info { min-width: 0; flex: 1; }
.file-chip-name {
  font-size: 0.78rem;
  font-weight: 500;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.file-chip-meta {
  font-size: 0.68rem;
  color: var(--text-faint);
}

.file-chip-remove {
  flex-shrink: 0;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  border: none;
  background: none;
  color: var(--text-faint);
  font-size: 0.7rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
}
.file-chip-remove:hover { background: var(--surface-3); color: var(--text); }

.msg-user-files {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.3rem;
  margin-bottom: 0.4rem;
}
.msg-user-files[hidden] { display: none; }

/* ---------- drag & drop overlay ---------- */
.drop-overlay {
  position: fixed;
  inset: 0;
  z-index: 60;
  background: rgba(28, 30, 33, 0.06);
  backdrop-filter: blur(2px);
  display: flex;
  align-items: center;
  justify-content: center;
  pointer-events: none;
}
.drop-overlay[hidden] { display: none; }

.drop-overlay-inner {
  background: #ffffff;
  border: 2px dashed var(--ink);
  border-radius: var(--radius-lg);
  padding: 2.5rem 3rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.6rem;
  color: var(--ink);
  box-shadow: var(--shadow-lg);
}
.drop-overlay-inner p {
  margin: 0;
  font-weight: 600;
  font-size: 0.95rem;
}

/* ---------- sidebar account row ---------- */
.account-row {
  margin-top: 0.6rem;
}

.account-login-btn {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: none;
  border: 1px solid var(--border-strong);
  color: var(--text);
  padding: 0.5rem 0.6rem;
  border-radius: 8px;
  font-size: 0.83rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.12s ease, border-color 0.12s ease;
}
.account-login-btn:hover { background: var(--surface-3); border-color: var(--text-faint); }

.account-signed-in {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.35rem 0.3rem;
}
.account-signed-in[hidden] { display: none; }

.account-avatar {
  flex-shrink: 0;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--accent);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
}

.account-email {
  flex: 1;
  min-width: 0;
  font-size: 0.8rem;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.account-logout-btn {
  flex-shrink: 0;
  width: 26px;
  height: 26px;
  border-radius: 6px;
  border: none;
  background: none;
  color: var(--text-faint);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
}
.account-logout-btn:hover { background: var(--surface-3); color: var(--text); }

/* ---------- auth modal ---------- */
.auth-overlay {
  position: fixed;
  inset: 0;
  background: rgba(36, 33, 27, 0.32);
  backdrop-filter: blur(2px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 55;
  padding: 1.5rem;
}
.auth-overlay[hidden] { display: none; }

.auth-panel {
  position: relative;
  width: 100%;
  max-width: 380px;
  background: #ffffff;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  padding: 2rem 1.75rem 1.75rem;
}

.auth-panel .settings-close {
  position: absolute;
  top: 0.9rem;
  right: 0.9rem;
}

.auth-view[hidden] { display: none; }

.auth-heading {
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 600;
  font-size: 1.4rem;
  letter-spacing: -0.01em;
  margin: 0 0 0.25rem;
  text-align: center;
  color: var(--text);
}
.auth-sub {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.85rem;
  margin: 0 0 1.4rem;
}
.auth-sub strong { color: var(--text); font-weight: 600; }

.google-btn {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  background: #ffffff;
  border: 1px solid var(--border-strong);
  border-radius: 9px;
  padding: 0.65rem;
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text);
  cursor: pointer;
  transition: background 0.12s ease, box-shadow 0.12s ease;
}
.google-btn:hover { background: var(--surface-2); box-shadow: var(--shadow-sm); }

.auth-divider {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  margin: 1.1rem 0;
  color: var(--text-faint);
  font-size: 0.75rem;
}
.auth-divider::before, .auth-divider::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--border);
}

.auth-form {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.auth-field {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}
.auth-field span:first-child {
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--text-muted);
}
.auth-field input {
  border: 1px solid var(--border-strong);
  border-radius: 8px;
  padding: 0.6rem 0.7rem;
  font-size: 0.88rem;
  font-family: var(--font-body);
  color: var(--text);
  background: #ffffff;
  transition: border-color 0.12s ease;
}
.auth-field input:focus {
  outline: none;
  border-color: var(--ink);
}
.auth-field-hint {
  font-size: 0.7rem;
  color: var(--text-faint);
}

.auth-error {
  background: var(--danger-soft);
  color: var(--danger);
  font-size: 0.8rem;
  padding: 0.55rem 0.7rem;
  border-radius: 7px;
  margin: 0;
}
.auth-error[hidden] { display: none; }

.auth-submit {
  background: var(--ink);
  color: #ffffff;
  border: none;
  border-radius: 8px;
  padding: 0.68rem;
  font-size: 0.88rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.12s ease, opacity 0.12s ease;
}
.auth-submit:hover:not(:disabled) { background: var(--ink-hover); }
.auth-submit:disabled { opacity: 0.55; cursor: default; }

.auth-switch {
  text-align: center;
  font-size: 0.82rem;
  color: var(--text-muted);
  margin: 1.2rem 0 0;
}
.auth-switch button {
  background: none;
  border: none;
  color: var(--accent);
  font-weight: 600;
  font-size: 0.82rem;
  cursor: pointer;
  padding: 0;
}
.auth-switch button:hover { text-decoration: underline; }

#verifyCode {
  text-align: center;
  font-size: 1.3rem;
  letter-spacing: 0.4em;
  font-weight: 600;
  padding-left: 0.3em;
}