:root {
  --bg: #f6f7f9;
  --panel: #ffffff;
  --panel-2: #f0f2f5;
  --border: #dfe3e8;
  --text: #14181f;
  --muted: #6b7480;
  --accent: #2f6df6;
  --accent-soft: #e8effe;
  --user-bg: #2f6df6;
  --user-fg: #ffffff;
  --code-bg: #f3f4f7;
  --danger: #c0392b;
  --danger-bg: #fdecea;
  --ok: #2eb872;
  --radius: 12px;
}

[data-theme="dark"] {
  --bg: #0f1115;
  --panel: #161a21;
  --panel-2: #1d222b;
  --border: #2a3140;
  --text: #e6e9ee;
  --muted: #98a2b3;
  --accent: #6f9bff;
  --accent-soft: #1c2740;
  --user-bg: #2f5bd0;
  --user-fg: #ffffff;
  --code-bg: #11151c;
  --danger: #ff8a80;
  --danger-bg: #341c1c;
  --ok: #3ddc97;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font: 15px/1.55 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

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

/* ---------------- sidebar ---------------- */

.sidebar {
  width: 290px;
  flex: 0 0 290px;
  background: var(--panel);
  border-right: 1px solid var(--border);
  padding: 18px 16px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  overflow-y: auto;
}
/* On desktop the sidebar simply disappears; on mobile it slides (see below). */
@media (min-width: 761px) {
  .sidebar.collapsed { display: none; }
}

.brand { display: flex; align-items: center; gap: 10px; }
.brand h1 { font-size: 17px; margin: 0; letter-spacing: -0.2px; }
.brand p { margin: 0; font-size: 12px; color: var(--muted); }

.dot {
  width: 9px; height: 9px; border-radius: 50%;
  background: var(--muted); flex: 0 0 auto;
}
.dot.ok { background: var(--ok); }
.dot.bad { background: var(--danger); }

.field { display: flex; flex-direction: column; gap: 6px; }
.field-label {
  display: flex; justify-content: space-between; align-items: center;
  font-size: 12px; font-weight: 600; color: var(--muted);
  text-transform: uppercase; letter-spacing: 0.04em;
}
.field-label b { color: var(--text); font-variant-numeric: tabular-nums; }

select, textarea, input[type="number"] {
  width: 100%;
  background: var(--panel-2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 9px;
  padding: 8px 10px;
  font: inherit;
  font-size: 14px;
}
select:focus, textarea:focus, input:focus {
  outline: 2px solid var(--accent-soft);
  border-color: var(--accent);
}
textarea { resize: vertical; }
input[type="range"] { width: 100%; accent-color: var(--accent); }

.meta { font-size: 11.5px; color: var(--muted); }

.link {
  background: none; border: none; padding: 0; cursor: pointer;
  color: var(--accent); font: inherit; font-size: 11px; text-transform: none;
}
.link:hover { text-decoration: underline; }

.spacer { flex: 1; }

button.secondary {
  background: var(--panel-2);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 9px;
  padding: 9px;
  font: inherit;
  cursor: pointer;
}
button.secondary:hover { background: var(--accent-soft); border-color: var(--accent); }

/* ---------------- main ---------------- */

.main { flex: 1; display: flex; flex-direction: column; min-width: 0; }

.topbar {
  display: flex; align-items: center; gap: 12px;
  padding: 12px 20px;
  border-bottom: 1px solid var(--border);
  background: var(--panel);
}
.topbar-title { display: flex; align-items: baseline; gap: 10px; min-width: 0; }
.topbar-title strong { font-size: 14px; }
.icon {
  background: none; border: 1px solid var(--border); color: var(--text);
  border-radius: 8px; width: 32px; height: 32px; cursor: pointer; font-size: 14px;
}
.icon:hover { background: var(--panel-2); }

.banner {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin: 12px 20px 0;
  padding: 10px 12px;
  border-radius: 9px;
  font-size: 13px;
  background: var(--danger-bg);
  color: var(--danger);
  border: 1px solid currentColor;
  word-break: break-word;
}
.banner > span { flex: 1; }
.banner-close {
  background: none;
  border: none;
  color: inherit;
  cursor: pointer;
  font-size: 18px;
  line-height: 1;
  padding: 0 2px;
  opacity: 0.7;
}
.banner-close:hover { opacity: 1; }
.banner.info {
  background: var(--accent-soft);
  color: var(--accent);
}
.hidden { display: none !important; }

.messages {
  flex: 1;
  overflow-y: auto;
  padding: 24px 20px 8px;
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.empty { margin: auto; text-align: center; color: var(--muted); }
.empty h2 { margin: 0 0 6px; font-size: 20px; color: var(--text); }
.empty p { margin: 0; font-size: 14px; }

.msg { display: flex; gap: 12px; max-width: 860px; width: 100%; margin: 0 auto; }
.msg .who {
  flex: 0 0 30px; height: 30px; border-radius: 8px;
  display: grid; place-items: center;
  font-size: 11px; font-weight: 700;
  background: var(--panel-2); color: var(--muted);
  border: 1px solid var(--border);
}
.msg.user .who { background: var(--user-bg); color: var(--user-fg); border-color: transparent; }
.msg .bubble { min-width: 0; flex: 1; }
.msg .bubble > *:first-child { margin-top: 0; }
.msg .bubble > *:last-child { margin-bottom: 0; }

.msg p { margin: 0 0 10px; white-space: pre-wrap; word-wrap: break-word; }
.msg ul, .msg ol { margin: 0 0 10px; padding-left: 22px; }
.msg li { margin: 2px 0; }
.msg h1, .msg h2, .msg h3 { margin: 14px 0 8px; line-height: 1.3; }
.msg h1 { font-size: 19px; } .msg h2 { font-size: 17px; } .msg h3 { font-size: 15px; }

.msg code {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 5px;
  padding: 1px 5px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 13px;
}
.msg pre {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 12px 14px;
  overflow-x: auto;
  margin: 0 0 10px;
}
.msg pre code { background: none; border: none; padding: 0; font-size: 13px; }

.msg.error .bubble { color: var(--danger); }

/* chain-of-thought from reasoning models */
.reasoning {
  margin: 0 0 10px;
  border: 1px dashed var(--border);
  border-radius: 9px;
  background: var(--panel-2);
}
.reasoning summary {
  cursor: pointer;
  padding: 7px 11px;
  font-size: 12px;
  font-weight: 600;
  color: var(--muted);
  list-style: none;
  user-select: none;
}
.reasoning summary::-webkit-details-marker { display: none; }
.reasoning summary::before { content: "▸ "; }
.reasoning[open] summary::before { content: "▾ "; }
.reasoning summary:hover { color: var(--text); }
.reasoning-body {
  padding: 0 12px 11px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--muted);
  white-space: pre-wrap;
  word-wrap: break-word;
  max-height: 320px;
  overflow-y: auto;
}

.cursor::after {
  content: "▍";
  animation: blink 1s steps(2, start) infinite;
  color: var(--accent);
}
@keyframes blink { to { visibility: hidden; } }

/* capability chips */
.chips { display: flex; flex-wrap: wrap; gap: 6px; }
.chip {
  font-size: 11px; padding: 3px 8px; border-radius: 20px;
  border: 1px solid var(--border); background: var(--panel-2);
  color: var(--muted); cursor: default;
}
.chip.on { border-color: var(--accent); color: var(--accent); background: var(--accent-soft); }

/* memory panel */
.mem-list { display: flex; flex-direction: column; gap: 4px; max-height: 190px; overflow-y: auto; }
.mem {
  display: flex; align-items: flex-start; gap: 6px;
  font-size: 12px; line-height: 1.4;
  background: var(--panel-2); border: 1px solid var(--border);
  border-radius: 7px; padding: 5px 7px;
}
.mem span { flex: 1; word-break: break-word; }
.mem-del {
  background: none; border: none; color: var(--muted);
  cursor: pointer; font-size: 14px; line-height: 1; padding: 0 2px;
}
.mem-del:hover { color: var(--danger); }
.mem-add { display: flex; gap: 6px; align-items: center; margin-top: 6px; }
.mem-add input {
  flex: 1; background: var(--panel-2); color: var(--text);
  border: 1px solid var(--border); border-radius: 7px;
  padding: 6px 8px; font: inherit; font-size: 12px;
}

/* tool activity */
.activity { display: flex; flex-direction: column; gap: 4px; margin: 0 0 10px; }
.act {
  display: flex; align-items: center; gap: 8px;
  font-size: 12px; color: var(--muted);
  background: var(--panel-2); border: 1px solid var(--border);
  border-radius: 7px; padding: 5px 9px;
}
.act-spin {
  width: 12px; text-align: center; flex: 0 0 12px;
  color: var(--accent); font-size: 11px;
}
.act.running .act-spin::after {
  content: "◐"; display: inline-block; animation: spin 1s linear infinite;
}
.act.done { opacity: 0.65; }
.act.done .act-spin { color: var(--ok); }
@keyframes spin { to { transform: rotate(360deg); } }

.msg a { color: var(--accent); }

/* ---------------- composer ---------------- */

.composer {
  display: flex;
  gap: 10px;
  align-items: flex-end;
  padding: 14px 20px 20px;
  max-width: 900px;
  width: 100%;
  margin: 0 auto;
}
.composer textarea {
  flex: 1;
  max-height: 220px;
  border-radius: var(--radius);
  padding: 11px 14px;
  background: var(--panel);
}
.composer button {
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  padding: 11px 20px;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  height: 44px;
}
.composer button:disabled { opacity: 0.5; cursor: not-allowed; }
.composer button.stop { background: var(--danger); }

/* ---------------- mobile ---------------- */

.backdrop { display: none; }

@media (max-width: 760px) {
  /* Sidebar becomes an overlay drawer that slides in from the left. */
  .sidebar {
    position: fixed;
    top: 0; left: 0; bottom: 0;
    width: min(86vw, 310px);
    flex: none;
    z-index: 30;
    transform: translateX(0);
    transition: transform 0.25s ease;
    box-shadow: 4px 0 28px rgba(0, 0, 0, 0.34);
    padding-bottom: 28px;
  }
  /* Stays laid out so the transform can animate - never display:none here. */
  .sidebar.collapsed {
    display: flex;
    transform: translateX(-100%);
  }

  .backdrop {
    display: block;
    position: fixed;
    inset: 0;
    z-index: 20;
    background: rgba(0, 0, 0, 0.45);
    opacity: 1;
    transition: opacity 0.25s ease;
  }
  .backdrop.hidden { opacity: 0; pointer-events: none; }

  /* Tighter chrome so the conversation gets the space. */
  .topbar { padding: 10px 12px; }
  .messages { padding: 16px 12px 4px; }
  .composer { padding: 10px 12px 14px; gap: 8px; }
  .composer button { padding: 11px 16px; }
  .banner { margin: 10px 12px 0; }
  .msg { gap: 9px; }
  .icon { width: 38px; height: 38px; font-size: 16px; }
}

/* Keep the send button reachable above mobile browser chrome. */
@supports (height: 100dvh) {
  .app { height: 100dvh; }
}