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

:root {
  --bg: #1a1a2e;
  --surface: #16213e;
  --border: #0f3460;
  --text: #e0e0e0;
  --text-muted: #8a8a9a;
  --accent: #e94560;
  --tab-active: #0f3460;
  --tab-hover: #1a2744;
  --font-mono: "SF Mono", "Fira Code", "Cascadia Code", Consolas, monospace;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
}

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  height: 100vh;
  overflow: hidden;
}

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

header {
  padding: 12px 20px;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

header h1 {
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
}

main {
  display: flex;
  flex: 1;
  min-height: 0;
}

.pane {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
}

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

.tabs {
  display: flex;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
  flex-shrink: 0;
}

.tab {
  padding: 8px 16px;
  border: none;
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 13px;
  font-family: var(--font-sans);
  border-bottom: 2px solid transparent;
  transition:
    color 0.15s,
    border-color 0.15s;
}

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

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

.editor {
  flex: 1;
  width: 100%;
  padding: 16px;
  border: none;
  background: var(--surface);
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 14px;
  line-height: 1.6;
  resize: none;
  outline: none;
  tab-size: 2;
}

.editor::placeholder {
  color: var(--text-muted);
}

.output {
  flex: 1;
  padding: 16px;
  overflow: auto;
  background: var(--surface);
  font-size: 14px;
  line-height: 1.6;
}

pre.output {
  font-family: var(--font-mono);
  white-space: pre-wrap;
  word-break: break-word;
}

#output-preview {
  font-family: var(--font-sans);
}

.hidden {
  display: none !important;
}

/* Preview area: basic Wikidot-like styles */
#output-preview h1,
#output-preview h2,
#output-preview h3,
#output-preview h4,
#output-preview h5,
#output-preview h6 {
  margin: 0.8em 0 0.4em;
  font-weight: 600;
}

#output-preview p {
  margin: 0.5em 0;
}

#output-preview ul,
#output-preview ol {
  padding-left: 1.5em;
  margin: 0.5em 0;
}

#output-preview blockquote {
  border-left: 3px solid var(--border);
  padding-left: 12px;
  margin: 0.5em 0;
  color: var(--text-muted);
}

#output-preview table {
  border-collapse: collapse;
  margin: 0.5em 0;
}

#output-preview th,
#output-preview td {
  border: 1px solid var(--border);
  padding: 4px 8px;
}

#output-preview code {
  background: rgba(255, 255, 255, 0.06);
  padding: 2px 4px;
  border-radius: 3px;
  font-family: var(--font-mono);
  font-size: 0.9em;
}

#output-preview pre {
  background: rgba(255, 255, 255, 0.04);
  padding: 12px;
  border-radius: 4px;
  overflow-x: auto;
}

#output-preview a {
  color: var(--accent);
  text-decoration: none;
}

#output-preview a:hover {
  text-decoration: underline;
}

#output-preview hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 1em 0;
}

.error {
  color: var(--accent);
  font-style: italic;
}