:root {
  --bg: #0b1020;
  --card: #121a2b;
  --muted: #b0bec5;
  --text: #e5e7eb;
  --primary: #38bdf8;
  --accent: #22c55e;
  --warning: #f59e0b;
  --border: #1f2937;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  overflow-wrap: break-word;
  word-wrap: break-word;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 24px;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 20px;
}

h1, h2, h3 { margin-top: 0; }
.muted { color: var(--muted); }

input, button, textarea, select {
  font: inherit;
}

input, textarea {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px 12px;
  background: #0f172a;
  color: var(--text);
}

button {
  border: none;
  border-radius: 10px;
  padding: 10px 16px;
  background: var(--primary);
  color: #02111b;
  font-weight: 700;
  cursor: pointer;
  transition: opacity 0.2s;
}
button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}
button.secondary {
  background: #334155;
  color: var(--text);
}
button.ghost {
  background: transparent;
  border: 1px solid #475569;
  color: var(--muted);
}

.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.layout {
  display: grid;
  grid-template-columns: 38% 62%;
  gap: 16px;
  min-height: calc(100vh - 100px);
}

.left-panel, .right-panel {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 16px;
  overflow-wrap: break-word;
  word-wrap: break-word;
  min-width: 0;
}

.chat-box {
  height: 58vh;
  overflow-y: auto;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 12px;
  background: #0f172a;
}

.msg {
  margin-bottom: 10px;
  padding: 10px;
  border-radius: 10px;
  line-height: 1.55;
  white-space: pre-wrap;
  overflow-wrap: break-word;
  word-wrap: break-word;
}
.msg.user {
  background: rgba(56, 189, 248, 0.15);
  border: 1px solid rgba(56, 189, 248, 0.35);
}
.msg.assistant {
  background: rgba(34, 197, 94, 0.12);
  border: 1px solid rgba(34, 197, 94, 0.35);
}
/* Markdown-rendered elements inside messages */
.msg strong { color: #fbbf24; font-weight: 700; }
.msg em { color: var(--primary); font-style: italic; }

.row { display: flex; gap: 10px; margin-top: 10px; }
.row > * { flex: 1; }

.badge {
  display: inline-block;
  background: rgba(245, 158, 11, 0.15);
  color: #fbbf24;
  border: 1px solid rgba(245, 158, 11, 0.35);
  border-radius: 999px;
  padding: 3px 10px;
  font-size: 12px;
  flex-shrink: 0;
}

.provider-badge {
  display: inline-block;
  background: rgba(34, 197, 94, 0.12);
  color: #86efac;
  border: 1px solid rgba(34, 197, 94, 0.3);
  border-radius: 999px;
  padding: 3px 10px;
  font-size: 11px;
  flex-shrink: 0;
}

.image-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}
.image-grid img {
  width: 100%;
  aspect-ratio: 4/3;
  object-fit: cover;
  border-radius: 8px;
  border: 1px solid var(--border);
}

a { color: var(--primary); }

/* Activity header */
.activity-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
  flex-wrap: wrap;
  gap: 8px;
}
.activity-header h2 { margin: 0; font-size: 1.25rem; }
.header-badges { display: flex; gap: 8px; align-items: center; flex-shrink: 0; }

/* Back link */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  color: var(--muted);
  text-decoration: none;
  font-size: 13px;
  margin-bottom: 10px;
}
.back-link:hover { color: var(--primary); }

/* Spinner */
.spinner {
  display: inline-block;
  width: 16px;
  height: 16px;
  border: 2px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  vertical-align: middle;
  margin-right: 6px;
}
@keyframes spin { to { transform: rotate(360deg); } }

/* Skeleton loader */
.skeleton {
  background: linear-gradient(90deg, #1e293b 25%, #334155 50%, #1e293b 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s infinite;
  border-radius: 6px;
  height: 14px;
  margin-bottom: 8px;
}
.skeleton.wide { width: 90%; }
.skeleton.medium { width: 65%; }
.skeleton.short { width: 40%; }
@keyframes shimmer { 0% { background-position: 200% 0; } 100% { background-position: -200% 0; } }

/* --- RESPONSIVE: MOBILE --- */
@media (max-width: 900px) {
  html, body {
    overflow-x: hidden;
    width: 100%;
  }

  /* Nuclear containment: ALL block-level elements constrained */
  .container,
  .layout,
  .left-panel,
  .right-panel,
  .chat-box,
  .msg,
  .row,
  .card,
  .activity-header,
  .input-area,
  .image-grid,
  p {
    max-width: 100%;
    box-sizing: border-box;
  }

  .container {
    padding: 10px;
    width: 100%;
  }

  h1 {
    font-size: 1.1rem;
    overflow-wrap: break-word;
    word-break: break-word;
  }

  .layout {
    display: flex;
    flex-direction: column;
    gap: 12px;
    width: 100%;
    min-height: auto;
  }

  .grid-2 { grid-template-columns: 1fr; }

  .left-panel {
    max-height: 28vh;
    overflow-y: auto;
    overflow-x: hidden;
    padding: 12px;
    width: 100%;
  }

  .right-panel {
    display: flex;
    flex-direction: column;
    padding: 12px;
    width: 100%;
    overflow: hidden;
  }

  .chat-box {
    height: 38vh;
    min-height: 180px;
    flex: 1;
    padding: 8px;
    width: 100%;
    overflow-x: hidden;
    overflow-y: auto;
  }

  .msg {
    padding: 8px;
    font-size: 0.88rem;
    line-height: 1.45;
    white-space: normal;
    overflow-wrap: break-word;
    word-break: break-word;
  }

  .muted {
    overflow-wrap: break-word;
    word-break: break-word;
  }

  /* Activity header: stack vertically on mobile */
  .activity-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
    width: 100%;
  }
  .activity-header h2 {
    font-size: 1rem;
    overflow-wrap: break-word;
    word-break: break-word;
  }
  .header-badges {
    align-self: flex-start;
  }

  .image-grid {
    grid-template-columns: 1fr 1fr 1fr;
    gap: 4px;
    width: 100%;
  }
  .image-grid img {
    aspect-ratio: 1;
  }

  /* Buttons: ensure all 3 fit in one row */
  .row {
    flex-wrap: nowrap;
    gap: 6px;
    width: 100%;
  }
  .row > button {
    min-width: 0;
    padding: 8px 4px;
    font-size: 0.78rem;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }
  .row > textarea {
    font-size: 0.88rem;
    width: 100%;
  }

  /* Keep input area always visible */
  .input-area {
    position: sticky;
    bottom: 0;
    background: var(--card);
    padding-top: 6px;
    z-index: 10;
    width: 100%;
  }

  /* Card on home */
  .card {
    padding: 16px;
    width: 100%;
  }
  .card p.muted {
    font-size: 0.85rem;
  }
}

/* --- RESPONSIVE: TABLET --- */
@media (min-width: 901px) and (max-width: 1100px) {
  .layout { grid-template-columns: 35% 65%; }
}