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

body {
  overflow: hidden;
  display: flex;
  flex-direction: column;
  height: 100vh;
}

/* ---- Quick Access Toolbar ---- */
.qat {
  display: flex;
  align-items: center;
  padding: 1px 4px;
  background: var(--sz-color-active-title);
  gap: 1px;
  flex-shrink: 0;
  min-height: 20px;
}

.qat-btn {
  width: 20px;
  height: 18px;
  border: none;
  background: transparent;
  cursor: default;
  font-size: 11px;
  line-height: 18px;
  text-align: center;
  color: var(--sz-color-title-text);
  border-radius: 2px;
  padding: 0;
}

.qat-btn:hover {
  background: rgba(255, 255, 255, 0.25);
}

.qat-btn:active {
  background: rgba(0, 0, 0, 0.15);
}

/* ---- Ribbon Tab Bar ---- */
.ribbon-tabs {
  flex-shrink: 0;
  background: var(--sz-color-button-face);
  border-bottom: 1px solid var(--sz-color-button-shadow);
}

.ribbon-tab-bar {
  display: flex;
  align-items: flex-end;
  padding: 0 2px;
  gap: 0;
}

.ribbon-file-btn {
  padding: 4px 14px;
  font-size: 11px;
  font-weight: bold;
  border: none;
  background: var(--sz-color-highlight);
  color: var(--sz-color-highlight-text);
  cursor: default;
  border-radius: 3px 3px 0 0;
  margin-right: 2px;
}

.ribbon-file-btn:hover {
  filter: brightness(1.1);
}

.ribbon-tab {
  padding: 4px 12px;
  font-size: 11px;
  border: 1px solid transparent;
  border-bottom: none;
  background: transparent;
  color: var(--sz-color-button-text);
  cursor: default;
  border-radius: 3px 3px 0 0;
  position: relative;
  top: 1px;
}

.ribbon-tab:hover {
  background: var(--sz-color-button-highlight);
  border-color: var(--sz-color-button-shadow);
}

.ribbon-tab.active {
  background: var(--sz-color-window);
  border-color: var(--sz-color-button-shadow);
  color: var(--sz-color-window-text);
  font-weight: bold;
}

/* ---- Backstage (File menu) ---- */
.backstage {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 5000;
  background: rgba(0, 0, 0, 0.3);
}

.backstage.visible {
  display: flex;
}

.backstage-sidebar {
  width: 220px;
  background: var(--sz-color-highlight);
  display: flex;
  flex-direction: column;
  padding: 4px 0;
  box-shadow: 2px 0 8px rgba(0, 0, 0, 0.3);
}

.backstage-back {
  border: none;
  background: transparent;
  color: var(--sz-color-highlight-text);
  font-size: 18px;
  padding: 8px 16px;
  text-align: left;
  cursor: default;
}

.backstage-back:hover {
  background: rgba(255, 255, 255, 0.15);
}

.backstage-item {
  border: none;
  background: transparent;
  color: var(--sz-color-highlight-text);
  font-size: 12px;
  padding: 8px 24px;
  text-align: left;
  cursor: default;
  width: 100%;
}

.backstage-item:hover {
  background: rgba(255, 255, 255, 0.15);
}

.backstage-sep {
  height: 1px;
  background: rgba(255, 255, 255, 0.2);
  margin: 4px 12px;
}

.backstage-spacer {
  flex: 1;
}

.backstage-exit {
  margin-top: auto;
}

/* ---- Ribbon Panels ---- */
.ribbon-panel {
  display: none;
  flex-direction: row;
  align-items: stretch;
  padding: 2px 4px 0;
  background: var(--sz-color-window);
  border-bottom: 1px solid var(--sz-color-button-shadow);
  flex-shrink: 0;
  min-height: 82px;
  overflow-x: auto;
  overflow-y: hidden;
  user-select: none;
}

.ribbon-panel.active {
  display: flex;
}

.ribbon-panel::-webkit-scrollbar {
  height: 4px;
}

.ribbon-panel::-webkit-scrollbar-thumb {
  background: var(--sz-color-button-shadow);
  border-radius: 2px;
}

.ribbon-group {
  display: flex;
  flex-direction: column;
  padding: 2px 4px 0;
  min-width: 0;
  flex-shrink: 0;
}

.ribbon-group-content {
  display: flex;
  align-items: flex-start;
  gap: 2px;
  flex: 1;
  min-height: 0;
}

.ribbon-group-label {
  text-align: center;
  font-size: 9px;
  color: var(--sz-color-gray-text);
  padding: 1px 4px 2px;
  white-space: nowrap;
  border-top: 1px solid var(--sz-color-button-light, transparent);
}

.ribbon-sep {
  width: 1px;
  background: var(--sz-color-button-shadow);
  margin: 2px 3px;
  align-self: stretch;
  flex-shrink: 0;
  opacity: 0.4;
}

/* ---- Ribbon Buttons ---- */
.rb-btn {
  border: 1px solid transparent;
  background: transparent;
  cursor: default;
  color: var(--sz-color-button-text);
  font-size: 11px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 1px 3px;
  border-radius: 2px;
  white-space: nowrap;
}

.rb-btn:hover {
  background: var(--sz-color-button-highlight);
  border-color: var(--sz-color-button-shadow);
}

.rb-btn:active {
  background: var(--sz-color-button-shadow);
}

.rb-btn.active {
  background: var(--sz-color-highlight);
  color: var(--sz-color-highlight-text);
  border-color: var(--sz-color-button-shadow);
}

.rb-btn-lg {
  flex-direction: column;
  padding: 4px 8px;
  min-width: 44px;
  height: 100%;
  gap: 2px;
}

.rb-btn-lg .rb-icon-lg {
  font-size: 20px;
  line-height: 1;
}

.rb-btn-lg .rb-label {
  font-size: 9px;
}

.rb-btn-sm {
  gap: 4px;
  padding: 1px 4px;
  min-height: 20px;
  justify-content: flex-start;
}

.rb-btn-sm .rb-icon {
  font-size: 12px;
  width: 16px;
  text-align: center;
  flex-shrink: 0;
}

.rb-btn-sm .rb-label {
  font-size: 10px;
}

.rb-fmt {
  min-width: 22px;
  height: 22px;
  padding: 0 3px;
  font-size: 12px;
  line-height: 22px;
}

.rb-stack {
  display: flex;
  flex-direction: column;
  gap: 1px;
  justify-content: flex-start;
}

.rb-row {
  display: flex;
  align-items: center;
  gap: 2px;
  flex-wrap: nowrap;
}

.rb-zoom-row {
  align-items: center;
  gap: 4px;
}

.rb-zoom-slider {
  width: 100px;
  height: 14px;
  cursor: default;
}

.rb-zoom-value {
  font-size: 10px;
  min-width: 36px;
  text-align: center;
}

/* ---- Split panes ---- */
.split-container {
  flex: 1;
  display: flex;
  overflow: hidden;
  min-height: 0;
}

.split-container.source-only .preview-pane,
.split-container.source-only .splitter {
  display: none;
}

.split-container.preview-only .source-pane,
.split-container.preview-only .splitter {
  display: none;
}

/* ---- Source pane ---- */
.source-pane {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-width: 200px;
  overflow: hidden;
}

.source-pane textarea {
  flex: 1;
  border: none;
  outline: none;
  resize: none;
  padding: 8px;
  font-family: Consolas, 'Courier New', monospace;
  font-size: 13px;
  line-height: 1.5;
  background: var(--sz-color-window);
  color: var(--sz-color-window-text);
  tab-size: 2;
  white-space: pre-wrap;
  word-wrap: break-word;
  overflow-wrap: break-word;
}

/* ---- Splitter ---- */
.splitter {
  width: 4px;
  background: var(--sz-color-button-face);
  border-left: 1px solid var(--sz-color-button-shadow);
  border-right: 1px solid var(--sz-color-button-shadow);
  cursor: col-resize;
  flex-shrink: 0;
}

/* ---- Preview pane ---- */
.preview-pane {
  flex: 1;
  min-width: 200px;
  overflow: auto;
  padding: 12px 16px;
  background: var(--sz-color-window);
  color: var(--sz-color-window-text);
  font-family: Tahoma, Verdana, sans-serif;
  font-size: 12px;
  line-height: 1.5;
}

.preview-pane h1 { font-size: 22px; margin: 16px 0 8px; border-bottom: 1px solid var(--sz-color-button-shadow); padding-bottom: 4px; }
.preview-pane h2 { font-size: 18px; margin: 14px 0 6px; border-bottom: 1px solid var(--sz-color-button-face); padding-bottom: 3px; }
.preview-pane h3 { font-size: 15px; margin: 12px 0 4px; }
.preview-pane h4 { font-size: 13px; margin: 10px 0 4px; }
.preview-pane h5 { font-size: 12px; margin: 8px 0 4px; }
.preview-pane h6 { font-size: 11px; margin: 8px 0 4px; color: var(--sz-color-gray-text); }
.preview-pane p { margin: 6px 0; }
.preview-pane ul, .preview-pane ol { margin: 6px 0; padding-left: 24px; }
.preview-pane li { margin: 2px 0; }
.preview-pane blockquote { border-left: 3px solid var(--sz-color-button-shadow); padding-left: 12px; color: var(--sz-color-gray-text); margin: 6px 0; }
.preview-pane code { background: var(--sz-color-button-face); padding: 1px 4px; font-family: Consolas, monospace; font-size: 12px; border-radius: 2px; }
.preview-pane pre { background: var(--sz-color-button-face); padding: 8px; font-family: Consolas, monospace; font-size: 12px; overflow-x: auto; margin: 6px 0; border-radius: 3px; }
.preview-pane pre code { background: transparent; padding: 0; }
.preview-pane table { border-collapse: collapse; margin: 6px 0; }
.preview-pane th, .preview-pane td { border: 1px solid var(--sz-color-button-shadow); padding: 4px 8px; font-size: 12px; }
.preview-pane th { background: var(--sz-color-button-face); }
.preview-pane hr { border: none; border-top: 1px solid var(--sz-color-button-shadow); margin: 12px 0; }
.preview-pane a { color: var(--sz-color-hot-tracking); }
.preview-pane img { max-width: 100%; }

/* ---- Status bar ---- */
.status-bar {
  display: flex;
  align-items: center;
  padding: 2px 8px;
  background: var(--sz-color-button-face);
  border-top: 1px solid var(--sz-color-button-shadow);
  font-size: 11px;
  color: var(--sz-color-button-text);
  flex-shrink: 0;
  user-select: none;
  gap: 16px;
}

.status-bar .status-section {
  white-space: nowrap;
}

.status-spacer {
  flex: 1;
}

/* ---- Print styles ---- */
@media print {
  .qat,
  .ribbon-tabs,
  .ribbon-panel,
  .backstage,
  .status-bar,
  .dialog-overlay {
    display: none !important;
  }

  .split-container {
    overflow: visible !important;
  }

  .source-pane {
    display: none !important;
  }

  .splitter {
    display: none !important;
  }

  .preview-pane {
    overflow: visible !important;
  }
}

/* ---- Dialogs ---- */
.dialog-overlay {
  display: none;
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.3);
  z-index: 2000;
  justify-content: center;
  align-items: center;
}

.dialog-overlay.visible {
  display: flex;
}

.dialog {
  background: var(--sz-color-button-face);
  border: 2px outset var(--sz-color-button-shadow);
  min-width: 300px;
  max-width: 450px;
  box-shadow: 3px 3px 8px rgba(0,0,0,0.3);
}

.dialog-title {
  background: var(--sz-color-highlight);
  color: var(--sz-color-highlight-text);
  padding: 4px 8px;
  font-weight: bold;
  font-size: 11px;
  user-select: none;
}

.dialog-body {
  padding: 12px;
  font-size: 11px;
}

.dialog-body p {
  margin-bottom: 8px;
}

.dialog-buttons {
  display: flex;
  justify-content: flex-end;
  gap: 6px;
  padding: 8px 12px;
}

.dialog-buttons button {
  min-width: 72px;
  padding: 3px 12px;
  font-size: 11px;
  cursor: default;
}