:root {
  color-scheme: light dark;
  --bg: #0b0c0f;
  --surface: #12151a;
  --border: #2a2f3a;
  --text: #e6e9ef;
  --muted: #9aa3b2;
  --accent: #4f8cff;
}

* {
  box-sizing: border-box;
}

html, body {
  height: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji", "Segoe UI Emoji";
}

.app-header, .app-footer {
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}

.app-footer {
  border-top: 1px solid var(--border);
  border-bottom: none;
}

.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  gap: 16px;
}

.app-title {
  margin: 0;
  font-size: 16px;
  font-weight: 600;
}

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

.filename-label {
  color: var(--muted);
  font-size: 12px;
}

.filename-input {
  height: 32px;
  padding: 0 10px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text);
  min-width: 180px;
}

.btn {
  height: 32px;
  padding: 0 12px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: #1a1f29;
  color: var(--text);
  cursor: pointer;
}

.btn.primary {
  background: var(--accent);
  border-color: transparent;
  color: white;
}

.btn.tab {
  background: transparent;
  border-color: var(--border);
}

.btn.tab[aria-selected="true"] {
  background: #1a1f29;
  border-color: var(--accent);
}

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  height: calc(100vh - 112px);
}

.pane {
  min-width: 0;
  min-height: 0;
}

.editor-pane {
  border-right: 1px solid var(--border);
}

#editor {
  width: 100%;
  height: 100%;
  border: none;
  outline: none;
  padding: 16px;
  resize: none;
  color: var(--text);
  background: transparent;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  font-size: 14px;
  line-height: 1.6;
}

.preview-pane {
  overflow: auto;
}

#preview {
  padding: 16px 20px 48px;
}

/* Minimal Markdown styles */
.markdown-body h1, .markdown-body h2, .markdown-body h3,
.markdown-body h4, .markdown-body h5, .markdown-body h6 {
  margin: 1.2em 0 0.6em;
}

.markdown-body p, .markdown-body ul, .markdown-body ol, .markdown-body pre, .markdown-body blockquote {
  margin: 0.6em 0;
}

.markdown-body code, .markdown-body pre {
  background: #0f1218;
  border: 1px solid var(--border);
  border-radius: 6px;
}

.markdown-body code {
  padding: 2px 6px;
}

.markdown-body pre {
  padding: 12px;
  overflow: auto;
}

.app-footer {
  padding: 10px 16px;
  color: var(--muted);
  font-size: 12px;
}

@media (max-width: 900px) {
  .split {
    grid-template-columns: 1fr;
    height: calc(100vh - 160px);
  }
  .editor-pane {
    border-right: none;
    border-bottom: 1px solid var(--border);
  }
  .mobile-tabs { display: flex; gap: 6px; }
  .preview-pane, .editor-pane { display: none; }
  .split[data-view="editor"] .editor-pane { display: block; }
  .split[data-view="preview"] .preview-pane { display: block; }
  .split[data-view="both"] .editor-pane, .split[data-view="both"] .preview-pane { display: block; }
}