* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

/* ── Dark theme (default) ────────────────────────────────────── */
:root {
  --bg-primary:     #1a1a1a;
  --bg-secondary:   #252525;
  --bg-tertiary:    #333;
  --border:         #444;
  --text-primary:   #e0e0e0;
  --text-secondary: #888;
  --accent:         #60a5fa;
  --accent-hover:   #93c5fd;
  --success:        #10b981;
  --warning:        #f59e0b;
  --danger:         #ef4444;
}

/* ── Light theme overrides ───────────────────────────────────── */
html[data-theme="light"] {
  --bg-primary:     #f4f4f2;
  --bg-secondary:   #e8e8e5;
  --bg-tertiary:    #d8d8d4;
  --border:         #b4b4b0;
  --text-primary:   #1a1a18;
  --text-secondary: #5a5a56;
  --accent:         #2563eb;
  --accent-hover:   #1d4ed8;
  --success:        #059669;
  --warning:        #d97706;
  --danger:         #dc2626;
}

/* ── Base ────────────────────────────────────────────────────── */
body {
  font-family: "SF Mono", "Cascadia Code", "JetBrains Mono", "Fira Code",
    Monaco, "Courier New", monospace;
  background: var(--bg-primary);
  color: var(--text-primary);
  overflow: hidden;
  font-size: 13px;
}

.app {
  display: flex;
  flex-direction: column;
  height: 100vh;
}

/* ── Header ──────────────────────────────────────────────────── */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 16px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  -webkit-app-region: drag;
}

.header-left,
.header-right {
  display: flex;
  align-items: center;
  gap: 8px;
  -webkit-app-region: no-drag;
}

/* App wordmark */
.app-wordmark {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--text-primary);
  padding-right: 12px;
  border-right: 1px solid var(--border);
  margin-right: 4px;
  user-select: none;
  white-space: nowrap;
}

.header select,
.header button {
  padding: 5px 10px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: 2px;
  color: var(--text-primary);
  cursor: pointer;
  font-size: 12px;
  font-family: inherit;
}

.header button:hover {
  background: var(--border);
}

.header button.btn-delete {
  background: transparent;
  border: 1px solid var(--border);
  padding: 5px 8px;
  font-size: 13px;
}

.header button.btn-delete:hover {
  background: var(--danger);
  border-color: var(--danger);
}

.header button.btn-rename {
  background: transparent;
  border: 1px solid var(--border);
  padding: 5px 8px;
  font-size: 13px;
}

.header button.btn-rename:hover {
  background: var(--bg-tertiary);
}

.session-rename-input {
  padding: 5px 10px;
  background: var(--bg-tertiary);
  border: 1px solid var(--accent);
  border-radius: 2px;
  color: var(--text-primary);
  font-size: 12px;
  font-family: inherit;
  min-width: 140px;
  outline: none;
  box-shadow: 0 0 0 2px rgba(96, 165, 250, 0.2);
}

html[data-theme="light"] .session-rename-input {
  box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.2);
}

/* Theme toggle */
.theme-toggle {
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: lowercase;
  opacity: 0.7;
  transition: opacity 0.15s;
}

.theme-toggle:hover {
  opacity: 1;
  background: var(--bg-tertiary) !important;
}

/* Phase indicator */
.phase-indicator {
  display: flex;
  gap: 4px;
}

.phase-step {
  padding: 3px 10px;
  font-size: 11px;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  border-radius: 2px;
  background: var(--bg-tertiary);
  color: var(--text-secondary);
}

.phase-step.active {
  background: var(--accent);
  color: white;
}

.phase-step.complete {
  background: var(--success);
  color: white;
}

/* ── Branch Badge ────────────────────────────────────────────── */
.branch-badge {
  padding: 3px 10px;
  font-size: 11px;
  letter-spacing: 0.04em;
  border-radius: 2px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  cursor: pointer;
  font-family: inherit;
  white-space: nowrap;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}

.branch-badge:hover:not(:disabled) {
  background: var(--border);
  color: var(--text-primary);
  border-color: var(--accent);
}

.branch-badge.branch-copied {
  background: var(--success);
  border-color: var(--success);
  color: white;
}

/* ── Main Content ─────────────────────────────────────────────── */
.main-content {
  flex: 1;
  display: flex;
  overflow: hidden;
}

/* ── Document Pane ───────────────────────────────────────────── */
.document-pane {
  flex: 1;
  display: flex;
  flex-direction: column;
  border-right: 1px solid var(--border);
  min-width: 0;
  overflow: hidden;
}

.document-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 7px 16px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  font-size: 11px;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  color: var(--text-secondary);
}

.document-header button {
  padding: 3px 8px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: 2px;
  color: var(--text-primary);
  cursor: pointer;
  font-size: 11px;
  font-family: inherit;
  letter-spacing: 0.05em;
}

.document-header button:hover {
  background: var(--border);
}

.document-content {
  flex: 1;
  overflow-y: auto;
  padding: 24px;
}

.document-content.editing {
  font-family: inherit;
  font-size: 13px;
  line-height: 1.6;
  background: var(--bg-primary);
  border: none;
  resize: none;
  color: var(--text-primary);
}

.codemirror-editor {
  flex: 1;
  overflow: hidden;
  min-height: 0;
}

.codemirror-editor .cm-editor {
  height: 100%;
  max-width: 100%;
}

.codemirror-editor .cm-scroller {
  overflow: auto !important;
}

.codemirror-editor .cm-gutters {
  background: var(--bg-secondary);
  border-right: 1px solid var(--border);
}

.document-content.rendered {
  line-height: 1.7;
}

.document-content.rendered h1 {
  font-size: 22px;
  margin: 24px 0 16px;
  letter-spacing: -0.01em;
}
.document-content.rendered h2 {
  font-size: 17px;
  margin: 20px 0 12px;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.document-content.rendered h3 {
  font-size: 14px;
  margin: 16px 0 8px;
}
.document-content.rendered p {
  margin: 8px 0;
  line-height: 1.6;
}
.document-content.rendered code {
  background: var(--bg-tertiary);
  padding: 2px 6px;
  border-radius: 2px;
  font-size: 12px;
  font-family: inherit;
}
.document-content.rendered pre {
  background: var(--bg-tertiary);
  padding: 16px;
  border-radius: 2px;
  overflow-x: auto;
  margin: 16px 0;
}
.document-content.rendered pre code {
  background: none;
  padding: 0;
}
.document-content.rendered ul,
.document-content.rendered ol {
  margin: 12px 0;
  padding-left: 24px;
}
.document-content.rendered li {
  margin-bottom: 6px;
  line-height: 1.5;
}
.document-content.rendered ul.contains-task-list {
  list-style: none;
  padding-left: 0;
}
.document-content.rendered li.task-list-item {
  display: flex;
  align-items: flex-start;
  gap: 8px;
}
.document-content.rendered li.task-list-item input[type="checkbox"] {
  margin-top: 4px;
}
.document-content.rendered table {
  width: 100%;
  border-collapse: collapse;
  margin: 16px 0;
  font-size: 12px;
}
.document-content.rendered th,
.document-content.rendered td {
  padding: 8px 12px;
  text-align: left;
  border: 1px solid var(--border);
}
.document-content.rendered th {
  background: var(--bg-tertiary);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-size: 11px;
}
.document-content.rendered tr:nth-child(even) td {
  background: var(--bg-secondary);
}
.document-content.rendered blockquote {
  border-left: 3px solid var(--accent);
  margin: 16px 0;
  padding-left: 16px;
  color: var(--text-secondary);
}
.document-content.rendered hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 24px 0;
}
.document-content.rendered a {
  color: var(--accent);
  text-decoration: none;
}
.document-content.rendered a:hover {
  text-decoration: underline;
}
.document-content.rendered .empty {
  color: var(--text-secondary);
  font-style: italic;
}

.badge {
  background: var(--accent);
  color: white;
  padding: 2px 8px;
  border-radius: 2px;
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

/* ── Chat Pane ───────────────────────────────────────────────── */
.chat-pane {
  width: 380px;
  display: flex;
  flex-direction: column;
  background: var(--bg-secondary);
}

.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 16px;
}

.message {
  margin-bottom: 10px;
  padding: 9px 13px;
  border-radius: 4px;
  max-width: 90%;
  font-size: 13px;
  line-height: 1.5;
  white-space: pre-wrap;
}

.message.user {
  background: var(--accent);
  margin-left: auto;
  color: white;
}

.message.assistant {
  background: var(--bg-tertiary);
}

.message.loading {
  color: var(--text-secondary);
  font-style: italic;
}

.chat-input {
  display: flex;
  gap: 8px;
  padding: 12px;
  border-top: 1px solid var(--border);
}

.chat-input input {
  flex: 1;
  padding: 9px 13px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: 2px;
  color: var(--text-primary);
  font-size: 13px;
  font-family: inherit;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.chat-input input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 2px rgba(96, 165, 250, 0.2);
}

html[data-theme="light"] .chat-input input:focus {
  box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.2);
}

.chat-input button {
  padding: 9px 15px;
  background: var(--accent);
  border: none;
  border-radius: 2px;
  color: white;
  cursor: pointer;
  font-size: 12px;
  font-family: inherit;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  transition: background 0.15s;
}

.chat-input button:hover:not(:disabled) {
  background: var(--accent-hover);
}

.chat-input button:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

/* ── Action Bar ──────────────────────────────────────────────── */
.action-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 16px;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
}

.action-bar-left,
.action-bar-right {
  display: flex;
  align-items: center;
  gap: 16px;
}

.token-indicator {
  display: flex;
  align-items: center;
  gap: 8px;
}

.token-bar {
  width: 100px;
  height: 4px;
  background: var(--bg-tertiary);
  border-radius: 1px;
  overflow: hidden;
}

.token-fill {
  height: 100%;
  transition: width 0.3s ease;
}

.token-label {
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-secondary);
}

.permission-toggle {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 11px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--text-secondary);
  cursor: pointer;
}

.permission-toggle input {
  cursor: pointer;
}

.btn-secondary {
  padding: 6px 14px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border);
  border-radius: 2px;
  color: var(--text-primary);
  cursor: pointer;
  font-size: 12px;
  font-family: inherit;
  letter-spacing: 0.05em;
  transition: background 0.15s;
}

.btn-secondary:hover:not(:disabled) {
  background: var(--border);
}

.btn-secondary:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.btn-primary {
  padding: 6px 18px;
  background: var(--accent);
  border: none;
  border-radius: 2px;
  color: white;
  cursor: pointer;
  font-weight: 600;
  font-size: 12px;
  font-family: inherit;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  transition: background 0.15s;
}

.btn-primary:hover:not(:disabled) {
  background: var(--accent-hover);
}

.btn-primary:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.implementing-status {
  color: var(--success);
  font-size: 11px;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

/* ── Error Bar ───────────────────────────────────────────────── */
.error-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 16px;
  background: var(--danger);
  color: white;
  font-size: 12px;
  letter-spacing: 0.03em;
}

.error-bar button {
  background: none;
  border: none;
  color: white;
  font-size: 16px;
  cursor: pointer;
  padding: 0 4px;
}

.error-bar button:hover {
  opacity: 0.8;
}

/* ── Onboarding ──────────────────────────────────────────────── */
.onboarding h1 {
  font-size: 24px;
  margin-bottom: 8px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.onboarding h2 {
  font-size: 13px;
  margin-top: 28px;
  margin-bottom: 12px;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.onboarding p {
  margin: 12px 0;
  line-height: 1.6;
}

.onboarding ol {
  margin: 12px 0 12px 24px;
}

.onboarding li {
  margin: 8px 0;
  line-height: 1.5;
}

.onboarding pre {
  background: var(--bg-tertiary);
  padding: 12px 16px;
  border-radius: 2px;
  margin: 12px 0;
}

.onboarding code {
  font-family: inherit;
  font-size: 12px;
}

.onboarding a {
  color: var(--accent);
  text-decoration: none;
}

.onboarding a:hover {
  text-decoration: underline;
}

.onboarding-tip {
  margin-top: 28px;
  padding: 16px;
  background: var(--bg-tertiary);
  border-left: 3px solid var(--accent);
  border-radius: 0 2px 2px 0;
}