:root {
  color-scheme: light;
  --bg: #f3f4f6;
  --panel: #ffffff;
  --text: #1f2937;
  --muted: #6b7280;
  --brand: #000000;
  --border: #e5e7eb;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.site-header {
  padding: 24px 16px;
  text-align: center;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
}

.site-header h1 {
  margin: 0;
  font-size: 24px;
  letter-spacing: -0.5px;
}

.layout {
  flex: 1;
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 24px;
  padding: 24px;
  max-width: 1400px;
  margin: 0 auto;
  width: 100%;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  height: calc(100vh - 120px);
}

.panel-header {
  padding: 16px;
  border-bottom: 1px solid var(--border);
  background: #f9fafb;
}

.panel-header h2 {
  margin: 0;
  font-size: 16px;
  font-weight: 600;
}

.chat-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.chat-header p {
  margin: 4px 0 0;
  font-size: 13px;
  color: var(--muted);
}

.persona-list {
  padding: 12px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.persona-card {
  text-align: left;
  background: #fff;
  border: 1px solid var(--border);
  padding: 12px;
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.2s;
}

.persona-card:hover {
  background: #f9fafb;
  border-color: #d1d5db;
}

.persona-card.active {
  background: #000;
  border-color: #000;
  color: #fff;
}

.persona-card.active p,
.persona-card.active .tag {
  color: rgba(255, 255, 255, 0.8);
}

.persona-card h3 {
  margin: 0 0 4px;
  font-size: 15px;
}

.persona-card p {
  margin: 0 0 8px;
  font-size: 12px;
  color: var(--muted);
}

.tags {
  display: flex;
  gap: 4px;
  flex-wrap: wrap;
}

.tag {
  font-size: 10px;
  background: #f3f4f6;
  padding: 2px 6px;
  border-radius: 4px;
  color: #4b5563;
}

.persona-card.active .tag {
  background: rgba(255, 255, 255, 0.2);
  color: #fff;
}

.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
  background: #fff;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.message {
  display: flex;
  flex-direction: column;
  gap: 4px;
  max-width: 80%;
}

.message:nth-child(even) {
  align-self: flex-end;
  align-items: flex-end;
}

.message .meta {
  font-size: 11px;
  color: #9ca3af;
  margin: 0 4px;
}

.bubble {
  padding: 10px 14px;
  border-radius: 12px;
  font-size: 14px;
  line-height: 1.5;
  background: #f3f4f6;
  color: #1f2937;
}

.bubble.user {
  background: #000;
  color: #fff;
}

.quick-replies {
  padding: 12px 16px 0;
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.quick-buttons button {
  background: #fff;
  border: 1px solid var(--border);
  padding: 6px 12px;
  border-radius: 100px;
  font-size: 12px;
  cursor: pointer;
  transition: all 0.2s;
}

.quick-buttons button:hover {
  border-color: #000;
  color: #000;
}

.chat-input {
  padding: 16px;
  display: flex;
  gap: 10px;
}

.chat-input input {
  flex: 1;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 14px;
  outline: none;
}

.chat-input input:focus {
  border-color: #000;
}

.chat-input button {
  background: #000;
  color: #fff;
  border: none;
  padding: 0 20px;
  border-radius: 8px;
  font-weight: 500;
  cursor: pointer;
}

.chat-input button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.ghost-btn {
  background: transparent;
  border: 1px solid var(--border);
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 12px;
  cursor: pointer;
}

.ghost-btn:hover {
  border-color: #000;
}

@media (max-width: 768px) {
  .layout {
    grid-template-columns: 1fr;
    padding: 12px;
    height: auto;
    display: flex;
    flex-direction: column;
  }

  .panel {
    height: auto;
    min-height: auto;
  }
  
  .panel.personas {
    max-height: 240px;
  }
  
  .panel.chat {
    height: 600px;
  }
}