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

html, body {
  height: 100%;
  overflow: hidden;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: #fff;
  color: #222;
}

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

/* ── Toolbar ── */

#toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 12px;
  height: 44px;
  flex-shrink: 0;
  border-bottom: 1px solid #e0e0e0;
  background: #fafafa;
  gap: 8px;
}

#toolbar-actions {
  display: flex;
  align-items: center;
  gap: 2px;
}

#toolbar button {
  background: none;
  border: 1px solid transparent;
  border-radius: 4px;
  padding: 5px 9px;
  font-size: 13px;
  cursor: pointer;
  color: #555;
  font-family: inherit;
  line-height: 1;
}

#toolbar button svg {
  vertical-align: middle;
}

#toolbar button:hover {
  background: #e8e8e8;
  border-color: #ddd;
}

#toolbar button:active {
  background: #ddd;
}

.toolbar-divider {
  width: 1px;
  height: 20px;
  background: #ddd;
  margin: 0 4px;
}

#toolbar-info {
  display: flex;
  align-items: center;
  gap: 12px;
}

#word-count {
  font-size: 11px;
  color: #999;
  white-space: nowrap;
}

#export-btn {
  font-size: 11px !important;
  padding: 4px 10px !important;
  border: 1px solid #ccc !important;
  border-radius: 4px;
  color: #555;
}

#export-btn:hover {
  border-color: #999 !important;
  color: #222;
}

/* ── Editor Container ── */

#editor-container {
  flex: 1;
  display: grid;
  grid-template-columns: 1fr 1px 1fr;
  overflow: hidden;
}

.panel {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  position: relative;
}

.panel-label {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: #aaa;
  padding: 6px 20px 0;
  flex-shrink: 0;
}

.mode-toggle {
  position: relative;
  display: flex;
  align-items: center;
  gap: 0;
  padding-bottom: 2px;
}

.mode-btn {
  position: relative;
  font-size: 14px;
  padding: 4px 10px;
  border: none;
  background: none;
  color: #ccc;
  cursor: pointer;
  line-height: 1;
  transition: color 250ms ease;
}

.mode-btn:hover {
  color: #888;
}

.mode-btn.active {
  color: #333;
}

.mode-btn.mode-raw {
  font-family: 'SF Mono', 'Fira Code', 'Consolas', monospace;
  font-size: 13px;
  font-weight: 500;
}

.mode-btn.mode-styled {
  font-family: Georgia, 'Times New Roman', serif;
  font-size: 15px;
  letter-spacing: -0.02em;
}

.mode-underline {
  position: absolute;
  bottom: 0;
  height: 1.5px;
  background: #333;
  transition: left 250ms ease, width 250ms ease;
  border-radius: 1px;
}

.panel-divider {
  background: #e0e0e0;
}

/* ── Markdown Panel (textarea + overlay) ── */

.editor-wrapper {
  position: relative;
  flex: 1;
  overflow: hidden;
}

#markdown-input {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  font-family: 'SF Mono', 'Fira Code', 'Consolas', 'Monaco', monospace;
  font-size: 14px;
  line-height: 1.7;
  padding: 12px 20px 20px;
  border: none;
  resize: none;
  background: transparent;
  color: transparent;
  caret-color: #333;
  z-index: 2;
  overflow: auto;
  outline: none;
  tab-size: 2;
  white-space: pre-wrap;
  word-wrap: break-word;
}

#markdown-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  font-family: 'SF Mono', 'Fira Code', 'Consolas', 'Monaco', monospace;
  font-size: 14px;
  line-height: 1.7;
  padding: 12px 20px 20px;
  pointer-events: none;
  z-index: 1;
  overflow: hidden;
  white-space: pre-wrap;
  word-wrap: break-word;
  color: #333;
  margin: 0;
}

/* Syntax highlight classes */
.md-syntax { color: #bbb; }
.md-heading-text { font-weight: 700; }
.md-bold-text { font-weight: 700; }
.md-em-text { font-style: italic; }
.md-strike-text { text-decoration: line-through; }
.md-code-text { background: #f0f0f0; border-radius: 2px; padding: 0 2px; }
.md-link-text { color: #0066cc; }
.md-link-url { color: #999; }
.md-blockquote { color: #666; }
.md-hr { color: #bbb; }

/* ── Styled Editor (contenteditable) ── */

#styled-editor {
  display: none;
  flex: 1;
  outline: none;
  padding: 12px 20px 20px;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  font-size: 15px;
  line-height: 1.7;
  overflow: auto;
  word-wrap: break-word;
  overflow-wrap: break-word;
  color: #222;
}

#markdown-panel.styled-mode .editor-wrapper {
  display: none;
}

#markdown-panel.styled-mode #styled-editor {
  display: block;
}

/* Styled mode typography — mirrors rich text panel */
#styled-editor .md-syntax {
  color: #bbb;
  font-weight: normal;
  font-style: normal;
  text-decoration: none;
}

#styled-editor .s-line-h1 { font-size: 1.8em; font-weight: 700; margin: 0.6em 0 0.4em; }
#styled-editor .s-line-h2 { font-size: 1.4em; font-weight: 600; margin: 0.5em 0 0.3em; }
#styled-editor .s-line-h3 { font-size: 1.15em; font-weight: 600; margin: 0.4em 0 0.3em; }
#styled-editor .s-line-h1 .md-syntax,
#styled-editor .s-line-h2 .md-syntax,
#styled-editor .s-line-h3 .md-syntax {
  font-size: 0.55em;
  vertical-align: middle;
}

#styled-editor .s-bold { font-weight: 700; }
#styled-editor .s-em { font-style: italic; }
#styled-editor .s-strike { text-decoration: line-through; color: #888; }
#styled-editor .s-code {
  background: #f4f4f4;
  padding: 2px 5px;
  border-radius: 3px;
  font-family: 'SF Mono', 'Fira Code', 'Consolas', monospace;
  font-size: 0.9em;
}
#styled-editor .s-link { color: #0066cc; }
#styled-editor .s-url { color: #999; font-size: 0.85em; }
#styled-editor .s-line-bq {
  border-left: 3px solid #ddd;
  padding-left: 16px;
  color: #666;
}
#styled-editor .s-line-hr {
  color: #bbb;
  margin: 1.2em 0;
}
#styled-editor .s-empty { min-height: 1.7em; }

/* Active panel indicator */
.panel.active {
  box-shadow: inset 3px 0 0 #0066cc;
}

/* ── Rich Text Panel ── */

#richtext {
  flex: 1;
  outline: none;
  padding: 12px 20px 20px;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  font-size: 15px;
  line-height: 1.7;
  overflow: auto;
  word-wrap: break-word;
  overflow-wrap: break-word;
}

#richtext h1 { font-size: 1.8em; margin: 0.6em 0 0.4em; font-weight: 700; }
#richtext h2 { font-size: 1.4em; margin: 0.5em 0 0.3em; font-weight: 600; }
#richtext h3 { font-size: 1.15em; margin: 0.4em 0 0.3em; font-weight: 600; }
#richtext p { margin: 0 0 0.8em; }
#richtext a { color: #0066cc; text-decoration: underline; }
#richtext strong { font-weight: 700; }
#richtext em { font-style: italic; }
#richtext del { text-decoration: line-through; color: #888; }
#richtext code {
  background: #f4f4f4;
  padding: 2px 5px;
  border-radius: 3px;
  font-family: 'SF Mono', 'Fira Code', 'Consolas', monospace;
  font-size: 0.9em;
}
#richtext pre {
  background: #f4f4f4;
  padding: 12px 16px;
  border-radius: 4px;
  overflow-x: auto;
  margin: 0.8em 0;
}
#richtext pre code {
  background: none;
  padding: 0;
}
#richtext blockquote {
  border-left: 3px solid #ddd;
  margin: 0.8em 0;
  padding: 0.4em 0 0.4em 16px;
  color: #666;
}
#richtext ul, #richtext ol {
  margin: 0 0 0.8em 1.5em;
}
#richtext li {
  margin-bottom: 0.3em;
}
#richtext hr {
  border: none;
  border-top: 1px solid #ddd;
  margin: 1.2em 0;
}

/* ── Link Tooltip ── */

#link-tooltip {
  display: none;
  position: fixed;
  align-items: center;
  gap: 6px;
  background: #fff;
  border: 1px solid #ddd;
  border-radius: 6px;
  padding: 6px 10px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  z-index: 1000;
}

#link-tooltip.visible {
  display: flex;
}

#link-url-input {
  border: 1px solid #ddd;
  border-radius: 4px;
  padding: 5px 8px;
  font-size: 13px;
  font-family: inherit;
  width: 260px;
  outline: none;
}

#link-url-input:focus {
  border-color: #0066cc;
}

#link-apply {
  background: #0066cc;
  color: #fff;
  border: none;
  border-radius: 4px;
  padding: 5px 12px;
  font-size: 12px;
  cursor: pointer;
  font-family: inherit;
}

#link-apply:hover {
  background: #0052a3;
}

#link-cancel {
  background: none;
  border: none;
  font-size: 16px;
  cursor: pointer;
  color: #999;
  padding: 2px 6px;
  line-height: 1;
}

#link-cancel:hover {
  color: #333;
}