:root {
  --bg: #f6f6f4;
  --panel: #ffffff;
  --panel-2: #efefec;
  --border: #e0e0db;
  --text: #1c1d1f;
  --muted: #6b6d72;
  --accent: #3b5bdb;
  --accent-soft: #e7ecfd;
  --gold: #a87b16;
  --gold-soft: #faf3e1;
  --danger: #c92a2a;
  --code-bg: #f1f1ee;
  --shadow: 0 1px 2px rgba(0,0,0,.05), 0 4px 16px rgba(0,0,0,.04);
  --radius: 12px;
  --sidebar-w: 270px;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #14161a; --panel: #1c1f24; --panel-2: #24282e; --border: #2f343b;
    --text: #e6e7e9; --muted: #9298a1; --accent: #7c93f5; --accent-soft: #252c45;
    --gold: #e0b450; --gold-soft: #2e2817; --danger: #ff6b6b; --code-bg: #24282e;
    --shadow: 0 1px 2px rgba(0,0,0,.3); color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --bg: #14161a; --panel: #1c1f24; --panel-2: #24282e; --border: #2f343b;
  --text: #e6e7e9; --muted: #9298a1; --accent: #7c93f5; --accent-soft: #252c45;
  --gold: #e0b450; --gold-soft: #2e2817; --danger: #ff6b6b; --code-bg: #24282e;
  --shadow: 0 1px 2px rgba(0,0,0,.3); color-scheme: dark;
}

* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
body {
  background: var(--bg); color: var(--text);
  font: 15px/1.55 -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, sans-serif;
  -webkit-font-smoothing: antialiased;
}
.hidden { display: none !important; }
.muted { color: var(--muted); }
.error-text { color: var(--danger); font-size: 13px; min-height: 0; }
button { font: inherit; color: inherit; cursor: pointer; }
select, input, textarea { font: inherit; color: var(--text); }

.btn {
  border: 1px solid var(--border); background: var(--panel); border-radius: 9px;
  padding: 8px 14px; transition: background .15s, border-color .15s;
}
.btn:hover { background: var(--panel-2); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn.primary:hover { filter: brightness(1.08); }
.btn.primary:disabled { opacity: .45; cursor: default; }
.btn.danger { background: var(--danger); border-color: var(--danger); color: #fff; }
.btn.small { padding: 5px 10px; font-size: 13px; }
.icon-btn { border: 0; background: none; font-size: 20px; padding: 4px 8px; border-radius: 8px; }
.icon-btn:hover { background: var(--panel-2); }
.link { border: 0; background: none; color: var(--muted); padding: 0; font-size: 13px; }
.link:hover { color: var(--text); }

/* ─── Login ─── */
.login { min-height: 100%; display: grid; place-items: center; padding: 16px; }
.login-card {
  width: 100%; max-width: 340px; background: var(--panel); border: 1px solid var(--border);
  border-radius: 16px; padding: 32px 24px; box-shadow: var(--shadow);
  display: flex; flex-direction: column; gap: 12px; text-align: center;
}
.login-logo { font-size: 40px; }
.login-card h1 { margin: 0; font-size: 22px; }
.login-card p { margin: 0 0 8px; }
.login-card input {
  padding: 11px 12px; border: 1px solid var(--border); border-radius: 9px; background: var(--bg);
}

/* ─── Layout ─── */
.app { display: flex; height: 100%; height: 100dvh; }
.sidebar {
  width: var(--sidebar-w); flex: none; background: var(--panel); border-right: 1px solid var(--border);
  display: flex; flex-direction: column; min-height: 0;
}
.sidebar-head { display: flex; align-items: center; justify-content: space-between; padding: 14px 12px; }
.brand { font-weight: 650; }
.conv-list { flex: 1; overflow-y: auto; padding: 0 8px; }
.conv-item {
  display: flex; align-items: center; gap: 6px; padding: 8px 10px; border-radius: 8px;
  cursor: pointer; font-size: 14px;
}
.conv-item:hover { background: var(--panel-2); }
.conv-item.active { background: var(--accent-soft); }
.conv-item .t { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.conv-item .m { font-size: 12px; opacity: .7; }
.conv-item .del { visibility: hidden; border: 0; background: none; color: var(--muted); padding: 0 4px; }
.conv-item:hover .del { visibility: visible; }
.conv-group { font-size: 11px; text-transform: uppercase; letter-spacing: .05em; color: var(--muted); padding: 12px 10px 4px; }
.sidebar-foot { padding: 12px; border-top: 1px solid var(--border); }
.scrim { display: none; }

.main { flex: 1; display: flex; flex-direction: column; min-width: 0; min-height: 0; }
.topbar {
  display: flex; align-items: center; gap: 10px; padding: 10px 16px;
  border-bottom: 1px solid var(--border); background: var(--panel);
}
#menu { display: none; }
.conv-title { flex: 1; font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.modes { display: flex; background: var(--panel-2); border-radius: 10px; padding: 3px; flex: none; }
.mode { border: 0; background: none; padding: 6px 12px; border-radius: 8px; font-size: 14px; color: var(--muted); }
.mode.active { background: var(--panel); color: var(--text); box-shadow: var(--shadow); }

/* ─── Config bar ─── */
.config {
  display: flex; flex-wrap: wrap; align-items: center; gap: 8px; padding: 10px 16px;
  border-bottom: 1px solid var(--border); background: var(--bg);
}
.pick {
  display: inline-flex; align-items: center; gap: 4px; background: var(--panel);
  border: 1px solid var(--border); border-radius: 10px; padding: 3px 4px 3px 8px;
}
.pick .n { font-size: 12px; color: var(--muted); font-weight: 600; }
.pick select { border: 0; background: transparent; padding: 4px 2px; max-width: 200px; }
.pick .x { border: 0; background: none; color: var(--muted); padding: 0 6px; font-size: 16px; }
.chip {
  display: inline-flex; align-items: center; gap: 6px; padding: 5px 11px; border-radius: 999px;
  border: 1px solid var(--border); background: var(--panel); font-size: 14px; user-select: none;
}
.chip.on { background: var(--accent-soft); border-color: var(--accent); }
.chip.chair { background: var(--gold-soft); border-color: var(--gold); cursor: default; }
.config .label { font-size: 13px; color: var(--muted); }
.config .sep { width: 1px; height: 22px; background: var(--border); margin: 0 4px; }

/* ─── Thread ─── */
.thread { flex: 1; overflow-y: auto; padding: 20px 16px 8px; }
.empty { max-width: 560px; margin: 10vh auto 0; text-align: center; }
.empty-icon { font-size: 44px; }
.empty h2 { margin: 8px 0; }
.turn { max-width: 1400px; margin: 0 auto 28px; }
.user-msg {
  max-width: 760px; margin: 0 0 14px auto; width: fit-content; background: var(--accent-soft);
  padding: 10px 14px; border-radius: 14px 14px 4px 14px; white-space: pre-wrap; word-wrap: break-word;
}
.answers { display: grid; gap: 12px; }
.answers.cols-1 { grid-template-columns: minmax(0, 900px); justify-content: center; }
.answers.cols-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.answers.cols-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.answers.cols-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.phase { text-align: center; color: var(--muted); font-size: 13px; margin: 14px 0 10px; }
.synthesis-wrap { display: grid; grid-template-columns: minmax(0, 900px); justify-content: center; margin-top: 12px; }

.card {
  background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius);
  box-shadow: var(--shadow); display: flex; flex-direction: column; min-width: 0;
}
.card.synthesis { border-color: var(--gold); background: linear-gradient(var(--gold-soft), var(--panel) 120px); }
.card-head {
  display: flex; align-items: center; gap: 8px; padding: 9px 14px; border-bottom: 1px solid var(--border);
  font-size: 13px;
}
.card-head .who { font-weight: 650; font-size: 14px; }
.card-head .model { color: var(--muted); }
.card-head .status { margin-left: auto; color: var(--muted); display: flex; align-items: center; gap: 6px; }
.dot { width: 7px; height: 7px; border-radius: 50%; background: var(--muted); }
.dot.running { background: var(--accent); animation: pulse 1s infinite ease-in-out; }
.dot.queued { background: var(--gold); }
.dot.error { background: var(--danger); }
.dot.done { background: #2f9e44; }
@keyframes pulse { 50% { opacity: .3; } }
.card-body { padding: 4px 14px 10px; overflow-wrap: anywhere; }
.card-body:empty::before { content: "…"; color: var(--muted); display: block; padding: 8px 0; }
.card-err { margin: 0 14px 10px; padding: 8px 10px; border-radius: 8px; background: color-mix(in srgb, var(--danger) 12%, transparent); color: var(--danger); font-size: 13px; white-space: pre-wrap; }
.tools { margin: 0 14px 10px; font-size: 12.5px; color: var(--muted); }
.tools summary { cursor: pointer; }
.tools ul { margin: 6px 0 0; padding-left: 18px; }
.tools code { font-size: 12px; }
.card-foot { padding: 0 14px 10px; font-size: 12px; color: var(--muted); display: flex; gap: 10px; }
.card-foot .copy { margin-left: auto; }

/* markdown */
.md > :first-child { margin-top: 8px; }
.md > :last-child { margin-bottom: 4px; }
.md p, .md ul, .md ol { margin: 8px 0; }
.md ul, .md ol { padding-left: 22px; }
.md h1, .md h2, .md h3, .md h4 { margin: 16px 0 6px; line-height: 1.3; }
.md h1 { font-size: 1.3em; } .md h2 { font-size: 1.18em; } .md h3 { font-size: 1.06em; }
.md code { background: var(--code-bg); padding: 1px 5px; border-radius: 5px; font-size: .9em; }
.md pre { background: var(--code-bg); padding: 10px 12px; border-radius: 8px; overflow-x: auto; }
.md pre code { background: none; padding: 0; }
.md table { border-collapse: collapse; display: block; overflow-x: auto; font-size: .93em; }
.md th, .md td { border: 1px solid var(--border); padding: 5px 9px; text-align: left; }
.md blockquote { margin: 8px 0; padding: 2px 12px; border-left: 3px solid var(--border); color: var(--muted); }
.md a { color: var(--accent); }
.md hr { border: 0; border-top: 1px solid var(--border); }

/* ─── Composer ─── */
.composer { padding: 10px 16px calc(12px + env(safe-area-inset-bottom)); background: var(--bg); }
.composer-inner {
  max-width: 900px; margin: 0 auto; display: flex; align-items: flex-end; gap: 8px;
  background: var(--panel); border: 1px solid var(--border); border-radius: 14px; padding: 8px;
  box-shadow: var(--shadow);
}
.composer-inner:focus-within { border-color: var(--accent); }
#input {
  flex: 1; border: 0; outline: 0; resize: none; background: transparent; padding: 6px 6px;
  max-height: 40vh; line-height: 1.45;
}
.send { width: 40px; height: 40px; padding: 0; border-radius: 10px; flex: none; }
.composer .error-text { max-width: 900px; margin: 6px auto 0; }

/* ─── Mobile ─── */
@media (max-width: 1100px) {
  .answers.cols-3, .answers.cols-4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 760px) {
  #menu { display: block; }
  .sidebar {
    position: fixed; inset: 0 auto 0 0; z-index: 20; transform: translateX(-100%);
    transition: transform .2s; box-shadow: var(--shadow);
  }
  .app.nav-open .sidebar { transform: none; }
  .app.nav-open .scrim { display: block; position: fixed; inset: 0; background: rgba(0,0,0,.35); z-index: 10; }
  .topbar { flex-wrap: wrap; padding: 8px 12px; }
  .modes { order: 3; width: 100%; }
  .mode { flex: 1; }
  .config { padding: 8px 12px; }
  .thread { padding: 14px 12px 8px; }
  .answers.cols-2, .answers.cols-3, .answers.cols-4 { grid-template-columns: minmax(0, 1fr); }
  .composer { padding: 8px 12px calc(10px + env(safe-area-inset-bottom)); }
  .pick select { max-width: 140px; }
}