/* ============ Theme: warm light, artisan ============ */
:root {
  --bg: #fbf7f0;
  --bg-2: #f4ede0;
  --surface: #ffffff;
  --surface-2: #fbf6ec;
  --line: #ebe2cf;
  --line-2: #dccfae;
  --ink: #2a2620;
  --ink-2: #5d564b;
  --ink-3: #9a9082;
  --accent: #d97757;
  --accent-2: #b8542f;
  --accent-soft: #f4d9c5;
  --olive: #6b7a4a;
  --user-bg: #2a2620;
  --user-fg: #fbf7f0;
  --ok: #6b7a4a;
  --warn: #c9892b;
  --err: #b8462f;
  --shadow-sm: 0 1px 2px rgba(70, 50, 30, 0.04);
  --shadow: 0 8px 24px rgba(70, 50, 30, 0.06);
  --serif: "Noto Serif SC", "Songti SC", Georgia, serif;
  --sans: "Inter", -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
}
* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
html { color-scheme: light; }
body {
  font-family: var(--sans);
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  background-image:
    radial-gradient(at 20% 8%, rgba(217,119,87,0.06), transparent 50%),
    radial-gradient(at 92% 95%, rgba(107,122,74,0.06), transparent 55%);
  background-attachment: fixed;
}
button { font-family: inherit; cursor: pointer; }
a { color: inherit; }
input, textarea, select, button { color: inherit; font-size: inherit; }

.app { display: grid; grid-template-columns: 264px 1fr; height: 100dvh; }

/* ============ Sidebar ============ */
.sidebar {
  display: flex; flex-direction: column;
  background: var(--surface-2);
  border-right: 1px solid var(--line);
  min-width: 0;
}
.sidebar-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 18px 16px 14px;
}
.brand { display: flex; gap: 11px; align-items: center; min-width: 0; }
.logo {
  width: 34px; height: 34px;
  background:
    radial-gradient(circle at 35% 30%, #f0a884 0%, transparent 50%),
    linear-gradient(135deg, var(--accent) 0%, var(--accent-2) 100%);
  border-radius: 10px;
  position: relative;
  box-shadow: 0 4px 12px rgba(217, 119, 87, 0.25);
}
.logo::after {
  content: ""; position: absolute; inset: 7px 8px;
  background: linear-gradient(135deg, transparent 30%, rgba(255,255,255,.4) 50%, transparent 70%);
  border-radius: 4px;
}
.brand-text { line-height: 1.2; min-width: 0; }
.brand-title {
  font-family: var(--serif);
  font-weight: 700; font-size: 17px;
  letter-spacing: 1px;
}
.brand-sub { font-size: 11px; color: var(--ink-3); margin-top: 2px; letter-spacing: .5px; }

.icon-btn {
  width: 36px; height: 36px;
  border-radius: 10px;
  border: 1px solid transparent;
  background: transparent;
  color: var(--ink-2);
  display: inline-flex; align-items: center; justify-content: center;
  transition: background .15s, color .15s, border-color .15s;
}
.icon-btn:hover {
  background: var(--surface); color: var(--ink); border-color: var(--line);
}

.new-chat-btn {
  margin: 0 14px 12px; padding: 10px 14px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  color: var(--ink);
  font-size: 14px; font-weight: 500;
  display: flex; align-items: center; gap: 8px;
  transition: all .15s;
  box-shadow: var(--shadow-sm);
}
.new-chat-btn:hover { border-color: var(--accent); color: var(--accent); }

.conversations { flex: 1; overflow-y: auto; padding: 4px 8px 12px; scrollbar-width: thin; }
.conv-item {
  display: flex; align-items: center; gap: 8px;
  padding: 9px 10px;
  border-radius: 10px;
  color: var(--ink-2);
  cursor: pointer;
  border: 1px solid transparent;
  user-select: none;
  transition: background .12s;
  margin-bottom: 2px;
}
.conv-item:hover { background: rgba(255,255,255,.6); color: var(--ink); }
.conv-item.active {
  background: var(--surface); border-color: var(--line); color: var(--ink);
  box-shadow: var(--shadow-sm);
}
.conv-item .conv-title {
  flex: 1; min-width: 0;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
  font-size: 14px;
}
.conv-item .conv-del {
  opacity: 0; transition: .15s;
  width: 24px; height: 24px; border-radius: 6px;
  display: inline-flex; align-items: center; justify-content: center;
  color: var(--ink-3); background: transparent; border: none;
}
.conv-item:hover .conv-del,
.conv-item.active .conv-del { opacity: 1; }
.conv-item .conv-del:hover { background: rgba(184,70,47,.1); color: var(--err); }

.sidebar-footer {
  border-top: 1px solid var(--line);
  padding: 14px 16px 16px;
  display: flex; flex-direction: column; gap: 10px;
}
.model-picker { display: flex; flex-direction: column; gap: 6px; }
.model-picker label { font-size: 11px; color: var(--ink-3); letter-spacing: .5px; }
.model-picker select {
  appearance: none; -webkit-appearance: none;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 9px 32px 9px 12px;
  font-size: 13px; color: var(--ink);
  background-image:
    linear-gradient(45deg, transparent 50%, var(--ink-3) 50%),
    linear-gradient(135deg, var(--ink-3) 50%, transparent 50%);
  background-position: right 14px center, right 9px center;
  background-size: 5px 5px, 5px 5px;
  background-repeat: no-repeat;
  transition: border-color .15s;
}
.model-picker select:focus { outline: none; border-color: var(--accent); }
.footer-row { display: flex; justify-content: space-between; align-items: center; gap: 8px; }

.text-btn {
  background: transparent;
  border: 1px solid var(--line);
  color: var(--ink-2);
  padding: 6px 10px;
  border-radius: 8px;
  font-size: 12px;
  transition: .15s;
}
.text-btn:hover { color: var(--ink); border-color: var(--line-2); background: var(--surface); }

.status { display: flex; align-items: center; gap: 7px; font-size: 11px; color: var(--ink-3); }
.dot {
  width: 7px; height: 7px; border-radius: 50%;
  background: var(--warn);
}
.dot.ok { background: var(--ok); box-shadow: 0 0 0 3px rgba(107,122,74,.2); }
.dot.err { background: var(--err); box-shadow: 0 0 0 3px rgba(184,70,47,.2); }

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

.topbar {
  display: flex; align-items: center; gap: 10px;
  padding: 14px 22px;
  border-bottom: 1px solid var(--line);
  background: rgba(251,247,240,.85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}
.topbar .title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: 16px;
  flex: 1; min-width: 0;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.only-mobile { display: none; }

/* user chip in topbar */
.user-chip {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 5px 10px 5px 5px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  cursor: pointer;
  transition: border-color .15s, background .15s;
  user-select: none;
  flex-shrink: 0;
}
.user-chip:hover { border-color: var(--line-2); background: var(--surface-2); }
.user-avatar {
  width: 26px; height: 26px; border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: white;
  font-size: 12px; font-weight: 600;
  font-family: var(--serif);
  display: inline-flex; align-items: center; justify-content: center;
  flex-shrink: 0;
}
.user-name {
  font-size: 13px; color: var(--ink);
  max-width: 100px;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}

/* user menu popover */
.user-menu {
  position: fixed;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 10px;
  box-shadow: 0 12px 36px rgba(70,50,30,.12);
  z-index: 30;
  min-width: 160px;
  display: none;
}
.user-menu.show { display: block; }
.user-menu-name {
  padding: 6px 10px 10px;
  font-size: 12px; color: var(--ink-3);
  border-bottom: 1px solid var(--line);
  margin-bottom: 6px;
  word-break: break-all;
}
.user-menu-item {
  display: block; width: 100%; text-align: left;
  background: transparent; border: 0;
  padding: 8px 10px; border-radius: 8px;
  font-size: 13px; color: var(--ink-2);
  cursor: pointer; font-family: inherit;
}
.user-menu-item:hover { background: var(--surface-2); color: var(--err); }

/* ============ Chat ============ */
.chat {
  flex: 1; overflow-y: auto;
  padding: 36px 22px 28px;
  scroll-behavior: smooth;
  scrollbar-gutter: stable;
}

/* Welcome */
.welcome {
  max-width: 720px; margin: 6vh auto 0;
  text-align: center;
  padding: 0 8px;
}
.welcome-art {
  margin: 0 auto 24px;
  width: 200px; height: 60px;
  color: var(--accent);
}
.welcome-art svg { width: 100%; height: 100%; }
.welcome h1 {
  font-family: var(--serif);
  font-size: clamp(26px, 4vw, 38px);
  font-weight: 700;
  margin: 0 0 10px;
  letter-spacing: 1px;
  color: var(--ink);
}
.welcome h1 .hl {
  color: var(--accent);
  font-style: italic;
  font-weight: 500;
}
.welcome-sub {
  color: var(--ink-3);
  margin: 0 0 36px;
  font-size: 13px;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  position: relative;
  display: inline-block;
}
.welcome-sub::before, .welcome-sub::after {
  content: ""; position: absolute; top: 50%;
  width: 30px; height: 1px; background: var(--line-2);
}
.welcome-sub::before { right: calc(100% + 14px); }
.welcome-sub::after { left: calc(100% + 14px); }

.prompts {
  display: grid; gap: 10px;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  max-width: 560px;
  margin: 0 auto;
}
.prompt-card {
  text-align: left;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 14px 16px;
  transition: .2s;
  display: flex; align-items: center; gap: 10px;
  color: var(--ink-2);
  font-size: 14px;
  box-shadow: var(--shadow-sm);
}
.prompt-card:hover {
  border-color: var(--accent);
  color: var(--ink);
  transform: translateY(-1px);
  box-shadow: var(--shadow);
}
.prompt-emoji {
  font-size: 16px; color: var(--accent);
  flex-shrink: 0;
}
.prompt-card em { font-style: normal; font-size: 13px; }

/* Messages */
.messages {
  max-width: 760px; margin: 0 auto;
  display: flex; flex-direction: column;
  gap: 24px;
}
.msg { display: flex; gap: 12px; align-items: flex-start; }
.msg.user { flex-direction: row-reverse; }
.avatar {
  flex: 0 0 auto;
  width: 30px; height: 30px;
  border-radius: 50%;
  display: inline-flex; align-items: center; justify-content: center;
  font-size: 12px; font-weight: 600;
  font-family: var(--serif);
  background: var(--surface);
  color: var(--ink);
  border: 1px solid var(--line);
}
.msg.assistant .avatar {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: white;
  border: none;
  box-shadow: 0 2px 8px rgba(217, 119, 87, 0.25);
}
.msg.user .avatar {
  background: var(--ink);
  color: var(--bg);
  border: none;
}

.bubble {
  max-width: min(680px, calc(100% - 50px));
  padding: 12px 16px;
  border-radius: 14px;
  line-height: 1.75;
  word-wrap: break-word;
  overflow-wrap: anywhere;
  font-size: 15px;
}
.msg.assistant .bubble {
  background: var(--surface);
  border: 1px solid var(--line);
  color: var(--ink);
  box-shadow: var(--shadow-sm);
}
.msg.user .bubble {
  background: var(--ink);
  color: var(--user-fg);
  border-radius: 14px 14px 4px 14px;
}
.msg.assistant .bubble { border-radius: 14px 14px 14px 4px; }

.bubble p { margin: 0 0 10px; }
.bubble p:last-child { margin: 0; }
.bubble h1, .bubble h2, .bubble h3 {
  font-family: var(--serif);
  margin: 16px 0 8px;
  line-height: 1.3;
}
.bubble h1 { font-size: 20px; }
.bubble h2 { font-size: 18px; }
.bubble h3 { font-size: 16px; }
.bubble ul, .bubble ol { padding-left: 22px; margin: 8px 0; }
.bubble li { margin: 4px 0; }
.bubble blockquote {
  margin: 10px 0; padding: 6px 14px;
  border-left: 3px solid var(--accent);
  background: var(--accent-soft);
  border-radius: 4px;
  color: var(--ink-2);
}
.msg.user .bubble blockquote {
  border-left-color: var(--bg);
  background: rgba(255,255,255,.1);
  color: var(--bg);
}
.bubble code {
  background: var(--bg-2);
  color: var(--accent-2);
  padding: 1px 6px;
  border-radius: 4px;
  font-family: ui-monospace, "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: .9em;
}
.msg.user .bubble code {
  background: rgba(255,255,255,.15);
  color: var(--bg);
}
.bubble pre {
  background: var(--surface-2);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0;
  margin: 12px 0;
  overflow: hidden;
}
.msg.user .bubble pre {
  background: rgba(255,255,255,.1);
  border-color: rgba(255,255,255,.2);
}
.bubble pre code {
  display: block;
  padding: 14px 16px;
  background: transparent;
  color: var(--ink);
  border-radius: 0;
  font-size: 13px;
  line-height: 1.6;
  overflow-x: auto;
}
.code-toolbar {
  display: flex; align-items: center; justify-content: space-between;
  padding: 7px 12px;
  background: var(--bg-2);
  border-bottom: 1px solid var(--line);
  font-size: 11px; color: var(--ink-3);
  letter-spacing: .5px;
}
.code-toolbar .lang { text-transform: lowercase; }
.copy-btn {
  background: transparent; border: 1px solid var(--line);
  color: var(--ink-2);
  border-radius: 6px;
  padding: 3px 9px;
  font-size: 11px;
  transition: .15s;
}
.copy-btn:hover { color: var(--accent); border-color: var(--accent); }
.copy-btn.copied { color: var(--ok); border-color: var(--ok); }

.bubble table { border-collapse: collapse; margin: 12px 0; width: 100%; font-size: 13px; }
.bubble th, .bubble td { border: 1px solid var(--line); padding: 7px 12px; text-align: left; }
.bubble th { background: var(--bg-2); font-weight: 600; }
.bubble a { color: var(--accent); text-decoration: underline; text-underline-offset: 2px; }

.cursor {
  display: inline-block; width: 6px; height: 14px;
  background: var(--accent); margin-left: 2px; vertical-align: -2px;
  animation: blink 1s steps(2) infinite;
}
@keyframes blink { 50% { opacity: 0; } }

.msg-actions {
  margin-top: 6px;
  display: flex; gap: 6px;
  opacity: 0; transition: opacity .15s;
}
.msg:hover .msg-actions { opacity: 1; }
.msg-actions button {
  background: transparent; border: 1px solid var(--line);
  color: var(--ink-3);
  padding: 3px 9px;
  border-radius: 6px;
  font-size: 11px;
  transition: .15s;
}
.msg-actions button:hover {
  color: var(--accent); border-color: var(--accent);
  background: var(--surface);
}

/* ============ Composer ============ */
.composer {
  padding: 14px 22px 14px;
  background: var(--bg);
  border-top: 1px solid var(--line);
}
.composer-inner {
  max-width: 760px; margin: 0 auto;
  display: flex; align-items: flex-end; gap: 10px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 10px 10px 10px 16px;
  transition: border-color .15s, box-shadow .15s;
  box-shadow: var(--shadow-sm);
}
.composer-inner:focus-within {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(217, 119, 87, 0.1);
}
.composer textarea {
  flex: 1;
  background: transparent;
  border: 0; outline: 0;
  resize: none;
  max-height: 200px;
  min-height: 24px;
  font-size: 15px;
  line-height: 1.5;
  padding: 4px 0;
  font-family: inherit;
}
.composer textarea::placeholder { color: var(--ink-3); }

.send-btn {
  width: 36px; height: 36px;
  border-radius: 50%;
  border: 0;
  background: var(--ink);
  color: var(--bg);
  display: inline-flex; align-items: center; justify-content: center;
  transition: transform .15s, background .15s;
  flex-shrink: 0;
}
.send-btn:hover { background: var(--accent); }
.send-btn:disabled {
  background: var(--line-2);
  color: var(--ink-3);
  cursor: not-allowed;
}
.send-btn.streaming { background: var(--err); }

.footnote {
  text-align: center;
  margin-top: 8px;
  font-size: 11px;
  color: var(--ink-3);
  letter-spacing: .5px;
}

/* ============ Dialog ============ */
.dialog {
  border: 0; padding: 0;
  background: transparent;
  color: var(--ink);
}
.dialog::backdrop {
  background: rgba(42, 38, 32, 0.4);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
}
.dialog-inner {
  width: min(520px, 92vw);
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 22px 22px 16px;
  box-shadow: 0 24px 60px rgba(70,50,30,.18);
}
.dialog-inner h2 {
  font-family: var(--serif);
  margin: 0 0 18px;
  font-size: 19px;
  font-weight: 700;
}
.dialog .row {
  display: flex; flex-direction: column; gap: 6px;
  margin-bottom: 14px;
}
.dialog .row > span {
  font-size: 13px; color: var(--ink-2);
  display: flex; justify-content: space-between;
}
.dialog .row > span small { color: var(--ink-3); font-weight: normal; }
.dialog input[type="number"], .dialog textarea {
  background: var(--surface-2);
  border: 1px solid var(--line);
  color: var(--ink);
  border-radius: 10px;
  padding: 9px 12px;
  font-size: 14px;
  font-family: inherit;
  resize: vertical;
}
.dialog input[type="number"]:focus, .dialog textarea:focus {
  outline: none;
  border-color: var(--accent);
}
.dialog input[type="range"] { accent-color: var(--accent); }
.dialog-actions { display: flex; justify-content: flex-end; gap: 8px; margin-top: 12px; }
.primary-btn {
  background: var(--ink);
  color: var(--bg);
  border: 0;
  padding: 8px 18px;
  border-radius: 10px;
  font-weight: 500;
  font-size: 13px;
  transition: background .15s;
}
.primary-btn:hover { background: var(--accent); }

/* ============ Scrollbar ============ */
::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-thumb { background: rgba(70,50,30,.12); border-radius: 8px; }
::-webkit-scrollbar-thumb:hover { background: rgba(70,50,30,.22); }
::-webkit-scrollbar-track { background: transparent; }

/* ============ Mobile (≤ 820px) ============ */
.scrim {
  position: fixed; inset: 0;
  background: rgba(42,38,32,.4);
  z-index: 25;
  opacity: 0; pointer-events: none;
  transition: opacity .2s;
  backdrop-filter: blur(2px);
}
.scrim.show { opacity: 1; pointer-events: auto; }

@media (max-width: 820px) {
  .app { grid-template-columns: 1fr; }

  .sidebar {
    position: fixed; inset: 0 auto 0 0;
    width: min(280px, 84vw);
    z-index: 30;
    transform: translateX(-100%);
    transition: transform .25s ease;
    box-shadow: 14px 0 40px rgba(70,50,30,.15);
  }
  .sidebar.open { transform: translateX(0); }

  .only-mobile { display: inline-flex; }

  .topbar {
    padding: 12px 14px;
    position: sticky; top: 0; z-index: 5;
    gap: 8px;
  }
  .topbar .title { font-size: 15px; flex: 1; min-width: 0; }
  .user-name { display: none; }
  .user-chip { padding: 4px; }

  .chat {
    padding: 22px 14px 16px;
    -webkit-overflow-scrolling: touch;
  }

  .welcome { margin-top: 5vh; padding: 0 4px; }
  .welcome-art { width: 160px; height: 50px; margin-bottom: 18px; }
  .welcome h1 { font-size: 26px; margin-bottom: 8px; }
  .welcome-sub { margin-bottom: 28px; font-size: 11px; }
  .welcome-sub::before, .welcome-sub::after { width: 22px; }

  .prompts {
    grid-template-columns: 1fr;
    gap: 8px;
    max-width: 360px;
  }
  .prompt-card { padding: 12px 14px; font-size: 14px; }

  .messages { gap: 18px; }
  .msg { gap: 10px; }
  .avatar { width: 28px; height: 28px; font-size: 11px; }
  .bubble {
    padding: 10px 14px;
    font-size: 15px;
    max-width: calc(100% - 40px);
    line-height: 1.7;
  }
  .bubble pre code { font-size: 12.5px; padding: 12px 14px; }

  .composer {
    padding: 10px 12px calc(10px + env(safe-area-inset-bottom, 0px));
  }
  .composer-inner {
    border-radius: 14px;
    padding: 8px 8px 8px 14px;
    align-items: flex-end;
  }
  .composer textarea {
    font-size: 16px;  /* prevent iOS zoom on focus */
    line-height: 1.45;
    max-height: 140px;
  }
  .send-btn { width: 34px; height: 34px; }

  /* hide msg-actions hover (touch can't hover) - use tap to copy via long-press not implemented, just always show subtle */
  .msg-actions { opacity: 1; }
  .msg-actions button { padding: 4px 10px; font-size: 11px; }

  .footnote { font-size: 10px; margin-top: 6px; }

  .dialog-inner { padding: 18px 18px 14px; border-radius: 14px; }
  .dialog-inner h2 { font-size: 17px; margin-bottom: 14px; }
}

@media (max-width: 380px) {
  .welcome h1 { font-size: 22px; }
  .topbar { padding: 10px 12px; }
  .chat { padding: 16px 10px 12px; }
}

/* respect "prefers-reduced-motion" */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}