/* ── arena.css — AI Arena Tabs + Chat + Visualizer UI ──────── */

#arena { background: var(--bg-primary); }

.arena-wrapper {
  background: var(--glass);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: 0 20px 60px rgba(0,0,0,0.4);
}

/* ── Tab Bar ─────────────────────────────────────────────────── */
.arena-tabs {
  display: flex;
  border-bottom: 1px solid var(--border);
  background: var(--bg-secondary);
  overflow-x: auto;
  scrollbar-width: none;
}
.arena-tabs::-webkit-scrollbar { display: none; }

.arena-tab {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 14px 20px;
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
  border-bottom: 2px solid transparent;
  transition: all var(--transition);
  position: relative;
}

.arena-tab:hover {
  color: var(--text-secondary);
  background: var(--glass);
}

.arena-tab.active {
  color: var(--text-primary);
  border-bottom-color: var(--tab-color, var(--accent-cyber));
}

.arena-tab .tab-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--tab-color, var(--accent-cyber));
  transition: box-shadow var(--transition);
}
.arena-tab.active .tab-dot {
  box-shadow: 0 0 8px var(--tab-color, var(--accent-cyber));
}

/* ── Tab Panels ─────────────────────────────────────────────── */
.arena-panel {
  display: none;
  height: 600px;
  flex-direction: column;
}

.arena-panel.active { display: flex; }

/* ── Panel Header ───────────────────────────────────────────── */
.panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 20px;
  border-bottom: 1px solid var(--border);
  background: var(--bg-secondary);
  flex-shrink: 0;
}

.panel-header-left {
  display: flex;
  align-items: center;
  gap: 10px;
}

.model-selector {
  background: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-size: 0.8rem;
  padding: 4px 10px;
  cursor: pointer;
  transition: border-color var(--transition);
}
.model-selector:focus { outline: none; border-color: var(--accent-cyber); }

.panel-header-right {
  display: flex;
  align-items: center;
  gap: 8px;
}

.panel-btn {
  padding: 5px 12px;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: 6px;
  background: var(--glass);
  border: 1px solid var(--border);
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition);
}
.panel-btn:hover {
  border-color: var(--border-hover);
  color: var(--text-primary);
}

/* ── Key Input Bar ──────────────────────────────────────────── */
.key-bar {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 16px;
  background: rgba(255,200,0,0.04);
  border-bottom: 1px solid rgba(240,192,64,0.15);
  font-size: 0.8rem;
  flex-shrink: 0;
}

.key-bar.hidden { display: none; }

.key-bar-label {
  color: var(--accent-gold);
  font-weight: 600;
  white-space: nowrap;
}

.key-bar input {
  flex: 1;
  background: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 5px 10px;
  color: var(--text-primary);
  font-family: var(--font-code);
  font-size: 0.78rem;
  min-width: 0;
  transition: border-color var(--transition);
}
.key-bar input:focus { outline: none; border-color: var(--accent-cyber); }

/* ── Chat Messages ──────────────────────────────────────────── */
.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  scrollbar-width: thin;
  scrollbar-color: var(--border) transparent;
}

.chat-messages::-webkit-scrollbar { width: 4px; }
.chat-messages::-webkit-scrollbar-track { background: transparent; }
.chat-messages::-webkit-scrollbar-thumb { background: var(--border); border-radius: 2px; }

.chat-empty {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  flex: 1;
  gap: 16px;
  color: var(--text-muted);
}

.chat-empty .empty-icon { font-size: 2.5rem; opacity: 0.5; }
.chat-empty p { font-size: 0.875rem; text-align: center; max-width: 300px; }

.chat-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  margin-top: 8px;
}

.chip {
  padding: 6px 14px;
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: 100px;
  font-size: 0.78rem;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
}
.chip:hover {
  border-color: var(--accent-cyber);
  color: var(--accent-cyber);
  background: var(--accent-cyber-dim);
}

.msg {
  display: flex;
  gap: 10px;
  max-width: 85%;
  animation: msgIn 0.3s ease;
}

@keyframes msgIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.msg.user { margin-left: auto; flex-direction: row-reverse; }

.msg-avatar {
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: var(--accent-cyber-dim);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  flex-shrink: 0;
  margin-top: 2px;
}

.msg.user .msg-avatar {
  background: var(--accent-maroon);
}

.msg-bubble {
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: 12px 12px 12px 4px;
  padding: 10px 14px;
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--text-secondary);
  word-break: break-word;
}

.msg.user .msg-bubble {
  background: rgba(134,38,51,0.12);
  border-color: rgba(134,38,51,0.25);
  border-radius: 12px 12px 4px 12px;
  color: var(--text-primary);
}

.msg-bubble pre {
  background: rgba(0,0,0,0.4);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 10px;
  overflow-x: auto;
  margin: 8px 0;
  font-size: 0.8rem;
}

.msg-bubble p { margin-bottom: 8px; color: inherit; }
.msg-bubble p:last-child { margin-bottom: 0; }
.msg-bubble strong { color: var(--text-primary); }

.typing-indicator {
  display: flex;
  gap: 4px;
  align-items: center;
  padding: 6px 0;
}

.typing-indicator span {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--text-muted);
  animation: typingDot 1.4s infinite;
}

.typing-indicator span:nth-child(2) { animation-delay: 0.2s; }
.typing-indicator span:nth-child(3) { animation-delay: 0.4s; }

@keyframes typingDot {
  0%, 60%, 100% { transform: translateY(0); opacity: 0.4; }
  30% { transform: translateY(-4px); opacity: 1; }
}

/* ── Chat Input ─────────────────────────────────────────────── */
.chat-input-area {
  padding: 14px 16px;
  border-top: 1px solid var(--border);
  flex-shrink: 0;
  background: var(--bg-secondary);
}

.chat-input-row {
  display: flex;
  gap: 10px;
  align-items: flex-end;
}

.chat-input {
  flex: 1;
  background: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 10px 14px;
  color: var(--text-primary);
  font-size: 0.875rem;
  resize: none;
  min-height: 44px;
  max-height: 120px;
  transition: border-color var(--transition);
  scrollbar-width: thin;
}
.chat-input:focus { outline: none; border-color: var(--accent-cyber); }
.chat-input::placeholder { color: var(--text-muted); }

.send-btn {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: var(--accent-cyber);
  border: none;
  color: var(--bg-primary);
  font-size: 1rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
  flex-shrink: 0;
}
.send-btn:hover { background: #fff; transform: scale(1.05); }
.send-btn:disabled { background: var(--text-muted); cursor: not-allowed; transform: none; }

/* ── Math Visualizer Panel ──────────────────────────────────── */
.visualizer-panel {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.viz-input-area {
  padding: 16px;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.viz-label {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 8px;
}

.viz-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 12px;
}

.viz-input-row {
  display: flex;
  gap: 10px;
}

.viz-input {
  flex: 1;
  background: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  color: var(--text-primary);
  font-size: 0.875rem;
  transition: border-color var(--transition);
}
.viz-input:focus { outline: none; border-color: var(--accent-cyber); }
.viz-input::placeholder { color: var(--text-muted); }

.viz-run-btn {
  padding: 10px 20px;
  background: var(--accent-cyber);
  color: var(--bg-primary);
  border: none;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 700;
  cursor: pointer;
  white-space: nowrap;
  transition: all var(--transition);
  display: flex;
  align-items: center;
  gap: 6px;
}
.viz-run-btn:hover { background: #fff; }
.viz-run-btn:disabled { background: var(--text-muted); cursor: not-allowed; }

.viz-output {
  flex: 1;
  overflow-y: auto;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  min-height: 0;
}

.viz-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  flex: 1;
  gap: 12px;
  color: var(--text-muted);
  text-align: center;
}

.viz-placeholder .big-icon { font-size: 3rem; opacity: 0.4; }

.pyodide-progress {
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 20px;
  display: none;
}

.pyodide-progress.visible { display: block; }

.progress-bar-wrap {
  height: 4px;
  background: var(--bg-primary);
  border-radius: 2px;
  overflow: hidden;
  margin: 10px 0;
}

.progress-bar-fill {
  height: 100%;
  background: var(--accent-cyber);
  border-radius: 2px;
  transition: width 0.3s ease;
}

.chart-result {
  display: none;
  flex-direction: column;
  gap: 10px;
}

.chart-result.visible { display: flex; }

.chart-result img {
  max-width: 100%;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
}

.chart-actions {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.code-collapse {
  background: var(--glass);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.code-collapse summary {
  padding: 10px 14px;
  font-size: 0.8rem;
  cursor: pointer;
  user-select: none;
  color: var(--text-secondary);
  font-weight: 600;
  list-style: none;
}
.code-collapse summary::-webkit-details-marker { display: none; }
.code-collapse summary::before {
  content: '▶ ';
  font-size: 0.65rem;
  color: var(--text-muted);
  transition: transform var(--transition);
}
.code-collapse[open] summary::before { content: '▼ '; }

.code-collapse pre {
  margin: 0;
  padding: 12px 14px;
  border-top: 1px solid var(--border);
  font-size: 0.78rem;
  overflow-x: auto;
  color: var(--accent-cyber);
}

/* ── Responsive ─────────────────────────────────────────────── */
@media (max-width: 768px) {
  .arena-panel { height: 500px; }
  .msg { max-width: 95%; }
  .panel-header { flex-wrap: wrap; gap: 8px; }
  .key-bar { flex-wrap: wrap; }
}