:root {
  --bg: #ffffff; --side: #f6f7f9; --line: #e3e6ea; --text: #1d2228; --muted: #6b7380;
  --accent: #2563eb; --accent-soft: #e8efff; --user: #eef3ff; --danger: #c62828; --warn-bg: #fff6e0;
  --code: #f3f4f6;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #16181c; --side: #1d2025; --line: #2e333a; --text: #e6e8eb; --muted: #9aa3ae;
    --accent: #5b8cff; --accent-soft: #22304d; --user: #22304d; --danger: #ef6c6c; --warn-bg: #3a3220; --code: #23272e; }
}
* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
body { font: 15px/1.5 -apple-system, "Segoe UI", Roboto, Arial, sans-serif; background: var(--bg); color: var(--text); }
a { color: var(--accent); }
button { font: inherit; cursor: pointer; }
input, select, textarea { font: inherit; color: var(--text); background: var(--bg); border: 1px solid var(--line); border-radius: 8px; padding: 8px 10px; }
textarea { resize: vertical; }
.muted { color: var(--muted); }
.btn { background: var(--accent); color: #fff; border: 0; border-radius: 8px; padding: 8px 14px; }
.btn.small { padding: 4px 10px; font-size: 13px; }
.btn.ghost { background: transparent; color: var(--text); border: 1px solid var(--line); }
.btn.danger { background: transparent; color: var(--danger); border: 1px solid var(--danger); }
.btn:disabled { opacity: .5; cursor: default; }
.icon-btn { background: transparent; border: 0; color: var(--muted); font-size: 18px; padding: 4px 8px; border-radius: 6px; }
.icon-btn:hover { background: var(--line); color: var(--text); }
.icon-btn.tiny { font-size: 13px; padding: 2px 6px; }
.link { background: none; border: 0; color: var(--accent); padding: 0 4px; font-size: 13px; }
.link:disabled { color: var(--muted); cursor: default; }
.alert { background: var(--warn-bg); border-left: 3px solid var(--danger); padding: 8px 10px; border-radius: 6px; margin: 8px 0; }
.note { background: var(--warn-bg); padding: 6px 10px; border-radius: 6px; margin-top: 8px; font-size: 13px; }
.check { display: flex; gap: 8px; align-items: center; }
.grow { flex: 1; }

/* вход */
.login-page { display: grid; place-items: center; min-height: 100%; background: var(--side); padding: 16px; }
.login-box { background: var(--bg); border: 1px solid var(--line); border-radius: 14px; padding: 28px; width: 100%; max-width: 360px; display: grid; gap: 14px; }
.login-box h1 { margin: 0 0 4px; font-size: 22px; }
.login-box label { display: grid; gap: 4px; }
.login-box label.check { display: flex; }
.login-box button { padding: 10px; }

/* раскладка */
.layout { display: flex; height: 100vh; height: 100dvh; }
.sidebar { width: 290px; flex: none; background: var(--side); border-right: 1px solid var(--line); display: flex; flex-direction: column; }
.side-head { display: flex; justify-content: space-between; align-items: center; padding: 14px 14px 8px; }
.branches { flex: 1; overflow-y: auto; padding: 0 8px 8px; }
.branch { margin-bottom: 4px; }
.branch-row { display: flex; align-items: center; }
.branch-name { flex: 1; text-align: left; background: none; border: 0; color: var(--text); padding: 7px 6px; border-radius: 6px; font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.branch.active > .branch-row .branch-name { color: var(--accent); }
.branch-name:hover { background: var(--line); }
.convs { padding-left: 14px; }
.conv { display: flex; align-items: center; border-radius: 6px; }
.conv .conv-title { flex: 1; padding: 6px 8px; cursor: pointer; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: 14px; }
.conv.new { background: none; border: 0; color: var(--accent); padding: 6px 8px; font-size: 13px; width: 100%; text-align: left; }
.conv:hover { background: var(--line); }
.conv.active { background: var(--accent-soft); }
.conv .conv-tools { display: none; }
.conv:hover .conv-tools, .conv.active .conv-tools { display: flex; }
.side-foot { border-top: 1px solid var(--line); padding: 10px 14px; font-size: 13px; }
.side-foot .warn { color: var(--danger); }
.foot-links { display: flex; gap: 14px; margin-top: 6px; flex-wrap: wrap; }
.backdrop { display: none; }

.main { flex: 1; display: flex; flex-direction: column; min-width: 0; overflow: hidden; }
.topbar { display: flex; align-items: center; gap: 10px; padding: 8px 14px; border-bottom: 1px solid var(--line); min-height: 52px; }
#menuBtn { display: none; }
.top-title { flex: 1; min-width: 0; font-weight: 600; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.top-tools { display: flex; align-items: center; gap: 10px; }
.top-tools select { max-width: 240px; padding: 5px 8px; font-size: 13px; }
.switch { display: flex; align-items: center; gap: 6px; font-size: 13px; white-space: nowrap; }

.messages { flex: 1; overflow-y: auto; padding: 18px 16px 8px; }
.empty { max-width: 520px; margin: 12vh auto; text-align: center; }
.msg { max-width: 820px; margin: 0 auto 16px; }
.msg.user .bubble { background: var(--user); border-radius: 14px; padding: 10px 14px; margin-left: auto; width: fit-content; max-width: 85%; }
.msg.assistant .bubble { padding: 2px 0; }
.text.plain { white-space: pre-wrap; word-wrap: break-word; }
.text { overflow-wrap: anywhere; }
.text p { margin: 0 0 10px; }
.text pre { background: var(--code); padding: 10px; border-radius: 8px; overflow-x: auto; }
.text code { background: var(--code); padding: 1px 4px; border-radius: 4px; font-size: 13px; }
.text table { border-collapse: collapse; display: block; overflow-x: auto; }
.text th, .text td { border: 1px solid var(--line); padding: 4px 8px; }
.status { color: var(--muted); font-size: 13px; font-style: italic; }
.status:empty { display: none; }
.tag { font-size: 12px; color: var(--accent); margin-bottom: 4px; }
.meta { font-size: 12px; color: var(--muted); margin-top: 6px; display: flex; flex-wrap: wrap; align-items: center; gap: 2px; }
.msg.user .meta { justify-content: flex-end; }
.sources { font-size: 13px; margin: 8px 0 0; padding-left: 22px; }
.sources a { word-break: break-word; }
.att-img { margin: 8px 0 0; display: inline-block; margin-right: 8px; }
.att-img img { max-width: 160px; max-height: 160px; border-radius: 8px; display: block; border: 1px solid var(--line); }
.att-img.big img { max-width: min(512px, 100%); max-height: 512px; }
.att-img figcaption { font-size: 13px; margin-top: 4px; }
.att-doc { display: inline-block; margin: 8px 8px 0 0; font-size: 13px; }

.composer { border-top: 1px solid var(--line); padding: 8px 14px calc(10px + env(safe-area-inset-bottom)); }
.composer > * { max-width: 820px; margin-left: auto; margin-right: auto; }
.modes { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 6px; }
.modes button { background: none; border: 1px solid var(--line); color: var(--muted); border-radius: 16px; padding: 3px 12px; font-size: 13px; }
.modes button.on { background: var(--accent-soft); border-color: var(--accent); color: var(--accent); }
.chips { display: flex; flex-wrap: wrap; gap: 6px; }
.chips:not(:empty) { margin-bottom: 6px; }
.chip { background: var(--side); border: 1px solid var(--line); border-radius: 14px; padding: 2px 6px 2px 10px; font-size: 13px; }
.chip button { background: none; border: 0; color: var(--muted); }
.input-row { display: flex; align-items: flex-end; gap: 6px; }
.input-row textarea { flex: 1; resize: none; max-height: 220px; border-radius: 12px; padding: 10px 12px; }
.attach { cursor: pointer; padding: 8px; }
.send { border-radius: 12px; padding: 9px 14px; }
.hint { font-size: 12px; margin-top: 4px; }
.hint:empty { display: none; }

dialog { border: 1px solid var(--line); border-radius: 14px; padding: 0; width: min(560px, calc(100vw - 32px)); background: var(--bg); color: var(--text); }
dialog form { padding: 20px; display: grid; gap: 12px; }
dialog h3 { margin: 0; }
dialog label { display: grid; gap: 4px; }
dialog label.check { display: flex; }
dialog::backdrop { background: rgba(0, 0, 0, .35); }
.dialog-actions { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }

/* настройки */
.page { max-width: 860px; margin: 0 auto; padding: 16px; }
.page h1 { font-size: 22px; }
.page section { border: 1px solid var(--line); border-radius: 12px; padding: 16px; margin-bottom: 16px; }
.page h2 { font-size: 17px; margin: 0 0 10px; }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.form-grid label { display: grid; gap: 4px; font-size: 14px; }
.form-grid small { color: var(--muted); }
.tbl { width: 100%; border-collapse: collapse; font-size: 14px; }
.tbl th, .tbl td { border-bottom: 1px solid var(--line); padding: 6px 4px; text-align: left; }
.tbl input { width: 100px; padding: 4px 6px; }
.tbl-wrap { overflow-x: auto; }
.ok { background: var(--accent-soft); padding: 8px 10px; border-radius: 6px; }

@media (max-width: 760px) {
  .sidebar { position: fixed; z-index: 20; top: 0; bottom: 0; left: 0; transform: translateX(-100%); transition: transform .2s; width: 82vw; max-width: 320px; }
  body.menu-open .sidebar { transform: none; }
  body.menu-open .backdrop { display: block; position: fixed; inset: 0; background: rgba(0, 0, 0, .35); z-index: 10; }
  #menuBtn { display: block; }
  .topbar { flex-wrap: wrap; padding: 6px 10px; }
  .top-title { flex-basis: calc(100% - 60px); }
  .top-tools { width: 100%; min-width: 0; }
  .top-tools select { flex: 1; max-width: none; }
  .switch span { font-size: 12px; }
  .messages { padding: 12px 10px 6px; }
  .msg.user .bubble { max-width: 92%; }
  .form-grid { grid-template-columns: 1fr; }
  .conv .conv-tools { display: flex; }
}