/* ── Reset ── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

/* Mermaid */
.mermaid {
  background: white;
  padding: 10px;
  border-radius: 4px;
  margin: 1em 0;
  display: flex;
  justify-content: center;
}
.mdr-theme-dark .mermaid {
  background: #2d2d2d;
}


/* ── Theme Variables ── */
body#mdr-body.mdr-theme-light {
  --bg:               #ffffff;
  --bg2:              #f6f8fa;
  --bg3:              #e8eaed;
  --text:             #1f2328;
  --text2:            #656d76;
  --border:           #d1d5da;
  --accent:           #0969da;
  --accent-fg:        #ffffff;
  --toolbar-bg:       #f6f8fa;
  --editor-bg:        #fafafa;
  --editor-text:      #1f2328;
  --preview-bg:       #ffffff;
  --code-bg:          #f0f0f0;
  --code-border:      #e0e0e0;
  --blockquote-left:  #d1d5da;
  --blockquote-text:  #656d76;
  --table-border:     #d1d5da;
  --table-header-bg:  #f6f8fa;
  --table-stripe:     #fafafa;
  --scrollbar:        #d1d5da;
}

body#mdr-body.mdr-theme-dark {
  --bg:               #0d1117;
  --bg2:              #161b22;
  --bg3:              #21262d;
  --text:             #e6edf3;
  --text2:            #8b949e;
  --border:           #30363d;
  --accent:           #58a6ff;
  --accent-fg:        #0d1117;
  --toolbar-bg:       #161b22;
  --editor-bg:        #0d1117;
  --editor-text:      #e6edf3;
  --preview-bg:       #0d1117;
  --code-bg:          #161b22;
  --code-border:      #30363d;
  --blockquote-left:  #3b434b;
  --blockquote-text:  #8b949e;
  --table-border:     #30363d;
  --table-header-bg:  #161b22;
  --table-stripe:     #0d1117;
  --scrollbar:        #30363d;
}

/* ── Base ── */
body#mdr-body {
  display: flex;
  flex-direction: column;
  height: 100vh;
  overflow: hidden;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;
  font-size: 15px;
  background: var(--bg);
  color: var(--text);
}

/* ── Scrollbars ── */
body#mdr-body ::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}
body#mdr-body ::-webkit-scrollbar-track {
  background: transparent;
}
body#mdr-body ::-webkit-scrollbar-thumb {
  background: var(--scrollbar);
  border-radius: 4px;
}
body#mdr-body ::-webkit-scrollbar-thumb:hover {
  background: var(--text2);
}

/* ── Toolbar ── */
#mdr-toolbar {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 0 16px;
  height: 44px;
  min-height: 44px;
  background: var(--toolbar-bg);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 1000;
  flex-shrink: 0;
}

#mdr-title {
  font-size: 13px;
  font-weight: 500;
  color: var(--text2);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 260px;
  flex-shrink: 0;
}

/* ── Mode Buttons ── */
#mdr-mode-btns {
  display: flex;
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  flex-shrink: 0;
}

#mdr-mode-btns button {
  background: var(--bg);
  color: var(--text2);
  border: none;
  border-right: 1px solid var(--border);
  padding: 5px 14px;
  font-size: 13px;
  font-family: inherit;
  cursor: pointer;
  transition: background 0.12s, color 0.12s;
  white-space: nowrap;
}

#mdr-mode-btns button:last-child {
  border-right: none;
}

#mdr-mode-btns button:hover {
  background: var(--bg3);
  color: var(--text);
}

#mdr-mode-btns button.mdr-active {
  background: var(--accent);
  color: var(--accent-fg);
}

/* ── Action Buttons ── */
#mdr-actions {
  margin-left: auto;
  display: flex;
  gap: 6px;
  flex-shrink: 0;
}

#mdr-actions button {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  padding: 5px 12px;
  border-radius: 6px;
  font-size: 13px;
  font-family: inherit;
  cursor: pointer;
  transition: background 0.12s;
  white-space: nowrap;
}

#mdr-actions button:hover {
  background: var(--bg3);
}

/* ── Main Layout ── */
#mdr-main {
  display: flex;
  flex: 1;
  overflow: hidden;
  min-height: 0;
}

/* View mode: preview only */
#mdr-main[data-mode="view"] #mdr-editor-pane {
  display: none;
}
#mdr-main[data-mode="view"] #mdr-preview-pane {
  flex: 1;
}

/* Split mode: 50/50 — preview left, editor right */
#mdr-main[data-mode="split"] #mdr-editor-pane {
  flex: 1;
  order: 2;
  border-left: 1px solid var(--border);
}
#mdr-main[data-mode="split"] #mdr-preview-pane {
  flex: 1;
  order: 1;
}

/* Edit mode: editor only */
#mdr-main[data-mode="edit"] #mdr-preview-pane {
  display: none;
}
#mdr-main[data-mode="edit"] #mdr-editor-pane {
  flex: 1;
}

/* ── Editor Pane ── */
#mdr-editor-pane {
  display: flex;
  flex-direction: column;
  background: var(--editor-bg);
  min-width: 0;
}

#mdr-editor-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 6px 16px;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.mdr-editor-label {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text2);
}

#mdr-char-count {
  font-size: 11px;
  color: var(--text2);
}

#mdr-editor {
  flex: 1;
  width: 100%;
  padding: 20px 24px;
  background: var(--editor-bg);
  color: var(--editor-text);
  border: none;
  outline: none;
  resize: none;
  font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
  font-size: 14px;
  line-height: 1.65;
  tab-size: 2;
  overflow-y: auto;
}

/* ── Preview Pane ── */
#mdr-preview-pane {
  overflow-y: auto;
  background: var(--preview-bg);
  min-width: 0;
}

#mdr-preview {
  max-width: 800px;
  margin: 0 auto;
  padding: 32px 40px 64px;
  line-height: 1.75;
  font-size: 16px;
  color: var(--text);
  word-break: break-word;
}

/* ── Preview Typography ── */
#mdr-preview h1,
#mdr-preview h2,
#mdr-preview h3,
#mdr-preview h4,
#mdr-preview h5,
#mdr-preview h6 {
  margin-top: 1.5em;
  margin-bottom: 0.6em;
  font-weight: 600;
  line-height: 1.3;
  color: var(--text);
}

#mdr-preview h1:first-child,
#mdr-preview h2:first-child {
  margin-top: 0;
}

#mdr-preview h1 {
  font-size: 2em;
  padding-bottom: 0.3em;
  border-bottom: 1px solid var(--border);
}

#mdr-preview h2 {
  font-size: 1.5em;
  padding-bottom: 0.3em;
  border-bottom: 1px solid var(--border);
}

#mdr-preview h3 { font-size: 1.25em; }
#mdr-preview h4 { font-size: 1em; }
#mdr-preview h5 { font-size: 0.875em; }
#mdr-preview h6 { font-size: 0.85em; color: var(--text2); }

#mdr-preview p {
  margin-bottom: 1em;
}

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

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

#mdr-preview strong { font-weight: 600; }
#mdr-preview em { font-style: italic; }
#mdr-preview del { color: var(--text2); }

/* ── Inline Code ── */
#mdr-preview code {
  background: var(--code-bg);
  border: 1px solid var(--code-border);
  padding: 0.15em 0.4em;
  border-radius: 4px;
  font-family: 'SFMono-Regular', Consolas, 'Liberation Mono', Menlo, monospace;
  font-size: 0.85em;
}

/* ── Code Blocks ── */
#mdr-preview pre {
  background: var(--code-bg);
  border: 1px solid var(--code-border);
  border-radius: 8px;
  padding: 16px 20px;
  overflow-x: auto;
  margin-bottom: 1em;
  line-height: 1.55;
}

#mdr-preview pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: 0.875em;
  color: var(--text);
}

/* ── Blockquote ── */
#mdr-preview blockquote {
  border-left: 4px solid var(--blockquote-left);
  color: var(--blockquote-text);
  padding: 4px 16px;
  margin: 0 0 1em 0;
}

#mdr-preview blockquote > *:last-child {
  margin-bottom: 0;
}

/* ── Lists ── */
#mdr-preview ul,
#mdr-preview ol {
  padding-left: 2em;
  margin-bottom: 1em;
}

#mdr-preview li {
  margin-bottom: 0.3em;
}

#mdr-preview li.mdr-task-item {
  list-style: none;
  margin-left: -1.5em;
  display: flex;
  align-items: baseline;
  gap: 0.4em;
}

#mdr-preview li.mdr-task-item input[type="checkbox"] {
  margin: 0;
  flex-shrink: 0;
}

/* ── Tables ── */
.mdr-table-wrap {
  overflow-x: auto;
  margin-bottom: 1em;
}

#mdr-preview table {
  border-collapse: collapse;
  min-width: 100%;
  font-size: 0.95em;
}

#mdr-preview th,
#mdr-preview td {
  border: 1px solid var(--table-border);
  padding: 7px 14px;
  text-align: left;
}

#mdr-preview th {
  background: var(--table-header-bg);
  font-weight: 600;
}

#mdr-preview tr:nth-child(even) td {
  background: var(--table-stripe);
}

/* ── Horizontal Rule ── */
#mdr-preview hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 1.5em 0;
}

/* ── Images ── */
#mdr-preview img {
  max-width: 100%;
  border-radius: 6px;
  display: block;
  margin: 0.5em 0;
}