/* BOS-X Surface — lean, self-contained styles (no build step, no deps).
   A two-pane demo shell: chat + streaming transcript on the left, live preview
   iframe on the right. Maps to ARCHITECTURE §2 (Surface). */

:root {
  --bg: #0c0d12;
  --bg-elev: #14161f;
  --bg-elev-2: #1b1e2b;
  --border: #262a3a;
  --border-soft: #1f2333;
  --text: #e7e9f2;
  --text-dim: #9aa0b5;
  --text-faint: #6b7186;
  --accent: #6d5cff;
  --accent-soft: #8b7dff;
  --ok: #34d399;
  --warn: #fbbf24;
  --err: #f87171;
  --radius: 12px;
  --radius-sm: 8px;
  --mono: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 14px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

.app {
  display: grid;
  grid-template-columns: 232px minmax(340px, 440px) 1fr;
  height: 100vh;
  overflow: hidden;
}

/* ── "Built apps" history rail (far left) ──────────────────────────────── */
.history {
  display: flex;
  flex-direction: column;
  min-width: 0;
  background: var(--bg);
  border-right: 1px solid var(--border);
}
.history__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 15px 14px 12px;
  border-bottom: 1px solid var(--border-soft);
}
.history__title {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.9px;
  color: var(--text-faint);
  font-weight: 600;
}
.history__refresh {
  background: transparent;
  border: 1px solid var(--border-soft);
  color: var(--text-faint);
  border-radius: var(--radius-sm);
  width: 24px; height: 22px;
  cursor: pointer;
  font-size: 13px;
  line-height: 1;
  transition: all 0.15s;
}
.history__refresh:hover { border-color: var(--accent); color: var(--text); }
.history__refresh.is-spinning { animation: spin 0.7s linear infinite; }

.history__list {
  flex: 1;
  overflow-y: auto;
  padding: 8px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  scrollbar-width: thin;
  scrollbar-color: var(--border) transparent;
}
.history__list::-webkit-scrollbar { width: 8px; }
.history__list::-webkit-scrollbar-thumb { background: var(--border); border-radius: 4px; }

.history__empty {
  margin: auto;
  text-align: center;
  color: var(--text-faint);
  font-size: 12px;
  padding: 20px 8px;
}

.history-item {
  text-align: left;
  display: flex;
  flex-direction: column;
  gap: 6px;
  width: 100%;
  background: var(--bg-elev);
  border: 1px solid var(--border-soft);
  border-left: 2px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 9px 10px;
  cursor: pointer;
  color: var(--text-dim);
  font-family: inherit;
  transition: border-color 0.15s, background 0.15s, transform 0.1s;
}
.history-item:hover { border-color: var(--border); border-left-color: var(--accent-soft); background: var(--bg-elev-2); transform: translateX(1px); }
.history-item.is-active {
  border-left-color: var(--accent);
  background: var(--bg-elev-2);
  box-shadow: inset 0 0 0 1px rgba(109, 92, 255, 0.25);
}
.history-item__prompt {
  font-size: 12.5px;
  line-height: 1.35;
  color: var(--text);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  word-break: break-word;
}
.history-item__meta {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}
.history-item__badge {
  font-family: var(--mono);
  font-size: 9.5px;
  letter-spacing: 0.2px;
  color: var(--accent-soft);
  background: rgba(109, 92, 255, 0.12);
  border: 1px solid rgba(109, 92, 255, 0.28);
  border-radius: 999px;
  padding: 1px 7px;
  white-space: nowrap;
}
.history-item__time {
  font-size: 10.5px;
  color: var(--text-faint);
  white-space: nowrap;
}

/* ── Chat pane ─────────────────────────────────────────────────────────── */
.chat {
  display: flex;
  flex-direction: column;
  min-width: 0;
  border-right: 1px solid var(--border);
  background: var(--bg-elev);
}

.chat__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 18px;
  border-bottom: 1px solid var(--border-soft);
}

.brand { display: flex; align-items: center; gap: 10px; }
.brand__mark {
  display: grid;
  place-items: center;
  width: 30px; height: 30px;
  border-radius: var(--radius-sm);
  background: linear-gradient(140deg, var(--accent), #4a3fd6);
  color: #fff;
  font-family: var(--mono);
  font-weight: 700;
  box-shadow: 0 2px 12px rgba(109, 92, 255, 0.35);
}
.brand__text { display: flex; flex-direction: column; line-height: 1.1; }
.brand__text strong { font-size: 15px; letter-spacing: 0.2px; }
.brand__text small { color: var(--text-faint); font-size: 11px; }

.status {
  display: flex; align-items: center; gap: 7px;
  padding: 5px 10px;
  background: var(--bg-elev-2);
  border: 1px solid var(--border-soft);
  border-radius: 999px;
  font-size: 12px;
  color: var(--text-dim);
}
.status__dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--text-faint);
  transition: background 0.2s;
}
.status[data-state="running"] .status__dot { background: var(--warn); animation: pulse 1.2s infinite; }
.status[data-state="done"] .status__dot { background: var(--ok); }
.status[data-state="error"] .status__dot { background: var(--err); }
@keyframes pulse { 0%,100% { opacity: 1; } 50% { opacity: 0.35; } }

/* ── Transcript ────────────────────────────────────────────────────────── */
.transcript {
  flex: 1;
  overflow-y: auto;
  padding: 18px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  scrollbar-width: thin;
  scrollbar-color: var(--border) transparent;
}
.transcript::-webkit-scrollbar { width: 8px; }
.transcript::-webkit-scrollbar-thumb { background: var(--border); border-radius: 4px; }

.empty {
  margin: auto;
  text-align: center;
  max-width: 320px;
  color: var(--text-dim);
}
.empty__art { font-size: 30px; color: var(--accent); opacity: 0.6; margin-bottom: 10px; }
.empty__examples { display: flex; flex-wrap: wrap; gap: 8px; justify-content: center; margin-top: 16px; }
.chip {
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  color: var(--text-dim);
  padding: 6px 11px;
  border-radius: 999px;
  font-size: 12px;
  cursor: pointer;
  transition: all 0.15s;
}
.chip:hover { border-color: var(--accent); color: var(--text); transform: translateY(-1px); }

/* message bubbles */
.msg { display: flex; flex-direction: column; gap: 4px; max-width: 92%; }
.msg--user { align-self: flex-end; align-items: flex-end; }
.msg--agent { align-self: flex-start; }
.msg__role {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: var(--text-faint);
  padding: 0 4px;
}
.msg__body {
  padding: 10px 13px;
  border-radius: var(--radius);
  white-space: pre-wrap;
  word-break: break-word;
  font-size: 13.5px;
}
.msg--user .msg__body {
  background: linear-gradient(140deg, var(--accent), #5648d8);
  color: #fff;
  border-bottom-right-radius: 4px;
}
.msg--agent .msg__body {
  background: var(--bg-elev-2);
  border: 1px solid var(--border-soft);
  border-bottom-left-radius: 4px;
}
.msg--agent .msg__body::after {
  content: "▍";
  color: var(--accent-soft);
  animation: blink 1s step-start infinite;
}
.msg--agent.is-done .msg__body::after { content: none; }
@keyframes blink { 50% { opacity: 0; } }

/* event log entries (tool calls, status, usage) */
.event {
  align-self: flex-start;
  max-width: 92%;
  display: flex;
  gap: 8px;
  align-items: flex-start;
  font-family: var(--mono);
  font-size: 11.5px;
  color: var(--text-dim);
  background: var(--bg-elev-2);
  border: 1px solid var(--border-soft);
  border-left: 2px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 7px 10px;
}
.event__icon { flex-shrink: 0; opacity: 0.8; }
.event__text { min-width: 0; word-break: break-word; }
.event__text b { color: var(--text); font-weight: 600; }
.event--tool { border-left-color: var(--accent); }
.event--tool-ok { border-left-color: var(--ok); }
.event--tool-err { border-left-color: var(--err); color: var(--err); }
.event--status { border-left-color: var(--warn); }
.event--usage { border-left-color: #5b8def; opacity: 0.75; }
.event--terminal { border-left-color: var(--ok); color: var(--text); }
.event--error { border-left-color: var(--err); color: var(--err); background: rgba(248,113,113,0.08); }

/* ── Composer ──────────────────────────────────────────────────────────── */
.composer {
  border-top: 1px solid var(--border-soft);
  padding: 12px 14px 14px;
  background: var(--bg-elev);
}
.composer__input {
  width: 100%;
  resize: none;
  max-height: 160px;
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-family: var(--sans);
  font-size: 14px;
  padding: 11px 13px;
  outline: none;
  transition: border-color 0.15s;
}
.composer__input:focus { border-color: var(--accent); }
.composer__input::placeholder { color: var(--text-faint); }

.composer__row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 10px;
  gap: 10px;
}
.engine {
  display: flex; align-items: center; gap: 7px;
  font-size: 11px; color: var(--text-faint);
  text-transform: uppercase; letter-spacing: 0.5px;
}
.engine__select {
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  color: var(--text-dim);
  border-radius: var(--radius-sm);
  padding: 5px 8px;
  font-size: 12px;
  font-family: var(--sans);
  text-transform: none;
  letter-spacing: 0;
  cursor: pointer;
}

.send {
  display: inline-flex; align-items: center; gap: 8px;
  background: linear-gradient(140deg, var(--accent), #5648d8);
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  padding: 9px 20px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.12s, opacity 0.12s, box-shadow 0.12s;
  box-shadow: 0 2px 10px rgba(109, 92, 255, 0.3);
}
.send:hover:not(:disabled) { transform: translateY(-1px); box-shadow: 0 4px 16px rgba(109,92,255,0.4); }
.send:disabled { opacity: 0.55; cursor: not-allowed; }
.send__spinner {
  width: 13px; height: 13px;
  border: 2px solid rgba(255,255,255,0.4);
  border-top-color: #fff;
  border-radius: 50%;
  display: none;
  animation: spin 0.7s linear infinite;
}
.send.is-busy .send__spinner { display: inline-block; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ── Preview pane ──────────────────────────────────────────────────────── */
.preview {
  display: flex;
  flex-direction: column;
  min-width: 0;
  background: var(--bg);
}
.preview__bar {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 14px;
  border-bottom: 1px solid var(--border-soft);
  background: var(--bg-elev);
}
.preview__dots { display: flex; gap: 6px; }
.preview__dots i { width: 11px; height: 11px; border-radius: 50%; background: var(--border); display: block; }
.preview__dots i:nth-child(1) { background: #ff5f57; opacity: 0.7; }
.preview__dots i:nth-child(2) { background: #febc2e; opacity: 0.7; }
.preview__dots i:nth-child(3) { background: #28c840; opacity: 0.7; }
.preview__url {
  flex: 1;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--text-faint);
  background: var(--bg-elev-2);
  border: 1px solid var(--border-soft);
  border-radius: 999px;
  padding: 5px 12px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.preview__open {
  background: var(--bg-elev-2);
  border: 1px solid var(--border);
  color: var(--text-dim);
  border-radius: var(--radius-sm);
  width: 30px; height: 28px;
  cursor: pointer;
  font-size: 14px;
  transition: all 0.15s;
}
.preview__open:hover:not(:disabled) { border-color: var(--accent); color: var(--text); }
.preview__open:disabled { opacity: 0.4; cursor: not-allowed; }

.preview__stage { flex: 1; position: relative; background: #fff; }
.preview__placeholder {
  position: absolute; inset: 0;
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  gap: 14px;
  background: var(--bg);
  color: var(--text-faint);
  text-align: center;
  padding: 30px;
}
.preview__placeholder-icon { font-size: 44px; color: var(--border); }
.preview__placeholder p { max-width: 280px; }
.preview__frame { width: 100%; height: 100%; border: 0; background: #fff; }

/* ── Responsive ─────────────────────────────────────────────────────────── */
/* Medium: drop the preview below, keep the rail + chat side by side. */
@media (max-width: 1100px) and (min-width: 721px) {
  .app { grid-template-columns: 200px 1fr; grid-template-rows: 1fr 1fr; }
  .history { grid-row: 1 / span 2; }
  .chat { border-right: none; border-bottom: 1px solid var(--border); }
}
/* Narrow: collapse the rail to a short horizontal strip, stack chat + preview. */
@media (max-width: 720px) {
  .app { grid-template-columns: 1fr; grid-template-rows: auto 1fr 1fr; }
  .history { border-right: none; border-bottom: 1px solid var(--border); max-height: 132px; }
  .history__list { flex-direction: row; overflow-x: auto; overflow-y: hidden; }
  .history-item { min-width: 180px; }
  .chat { border-right: none; border-bottom: 1px solid var(--border); }
}