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

body {
  overflow: hidden;
  user-select: none;
  -webkit-user-select: none;
  font: inherit;
  font-size: 12px;
  background: var(--sz-color-button-face);
  color: var(--sz-color-button-text);
  display: flex;
  flex-direction: column;
  height: 100vh;
}

/* ---- Layout ---- */
#app {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
  padding: 8px;
  overflow: hidden;
  gap: 6px;
}

.hidden { display: none !important; }

/* ---- Main content ---- */
#main-content {
  display: flex;
  flex: 1;
  min-height: 0;
  gap: 6px;
}

/* ---- Left sidebar ---- */
#sidebar {
  width: 220px;
  min-width: 220px;
  display: flex;
  flex-direction: column;
  border: 2px inset;
  border-color: var(--sz-color-button-shadow) var(--sz-color-button-highlight) var(--sz-color-button-highlight) var(--sz-color-button-shadow);
  background: var(--sz-color-window);
  color: var(--sz-color-window-text);
}

#sidebar-header {
  padding: 4px 8px;
  font-weight: bold;
  font-size: 11px;
  background: var(--sz-color-button-face);
  color: var(--sz-color-button-text);
  border-bottom: 1px solid var(--sz-color-button-shadow);
  flex-shrink: 0;
}

#category-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  background: var(--sz-color-button-face);
  border-bottom: 1px solid var(--sz-color-button-shadow);
  flex-shrink: 0;
  padding: 2px 2px 0;
}

.cat-tab {
  font: inherit;
  font-size: 10px;
  padding: 2px 6px;
  border: 1px solid var(--sz-color-button-shadow);
  border-bottom: none;
  background: var(--sz-color-button-face);
  color: var(--sz-color-button-text);
  cursor: pointer;
  margin-right: -1px;
}

.cat-tab.active {
  background: var(--sz-color-window);
  color: var(--sz-color-window-text);
  font-weight: bold;
  border-bottom: 1px solid var(--sz-color-window);
  margin-bottom: -1px;
}

.cat-tab:hover:not(.active) {
  background: var(--sz-color-button-highlight);
}

#pairs-list {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
}

.pair-item {
  padding: 6px 8px;
  cursor: pointer;
  border-bottom: 1px solid var(--sz-color-button-face);
  transition: background 0.1s;
}

.pair-item:hover {
  background: var(--sz-color-highlight);
  color: var(--sz-color-highlight-text);
}

.pair-item.active {
  background: var(--sz-color-highlight);
  color: var(--sz-color-highlight-text);
}

.pair-item-names {
  font-size: 11px;
  font-weight: bold;
  margin-bottom: 2px;
}

.pair-item-tag {
  font-size: 9px;
  opacity: 0.7;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 3px;
}

.pair-item-preview {
  display: flex;
  flex-direction: column;
  gap: 1px;
  padding: 3px 4px;
  background: var(--sz-color-window);
  border-radius: 2px;
}

.pair-item:hover .pair-item-preview,
.pair-item.active .pair-item-preview {
  background: var(--sz-color-window);
}

.pair-preview-heading {
  font-size: 13px;
  font-weight: 700;
  color: var(--sz-color-window-text);
  line-height: 1.2;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.pair-preview-body {
  font-size: 9px;
  color: var(--sz-color-gray-text);
  line-height: 1.3;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* ---- Preview area ---- */
#preview-area {
  flex: 1;
  border: 2px inset;
  border-color: var(--sz-color-button-shadow) var(--sz-color-button-highlight) var(--sz-color-button-highlight) var(--sz-color-button-shadow);
  overflow: auto;
  min-width: 0;
}

#preview-container {
  min-height: 100%;
  padding: 40px 48px;
  background: #ffffff;
  color: #1a1a1a;
  transition: background 0.3s, color 0.3s;
}

#preview-container.dark {
  background: #1a1a2e;
  color: #e8e8f0;
}

#preview-heading {
  font-size: 42px;
  font-weight: 700;
  line-height: 1.15;
  margin-bottom: 16px;
  outline: none;
  cursor: text;
  user-select: text;
  -webkit-user-select: text;
  word-wrap: break-word;
  overflow-wrap: break-word;
}

#preview-heading:focus {
  outline: 2px dashed rgba(100,100,255,0.4);
  outline-offset: 4px;
  border-radius: 2px;
}

#preview-divider {
  width: 60px;
  height: 3px;
  background: currentColor;
  opacity: 0.2;
  margin-bottom: 20px;
  border-radius: 2px;
}

#preview-body {
  font-size: 16px;
  font-weight: 400;
  line-height: 1.6;
  max-width: 680px;
  margin-bottom: 32px;
  outline: none;
  cursor: text;
  user-select: text;
  -webkit-user-select: text;
  word-wrap: break-word;
  overflow-wrap: break-word;
}

#preview-body:focus {
  outline: 2px dashed rgba(100,100,255,0.4);
  outline-offset: 4px;
  border-radius: 2px;
}

#preview-weights {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding-top: 20px;
  border-top: 1px solid;
  border-color: inherit;
  opacity: 0.15;
}

#preview-container:not(.dark) #preview-weights {
  border-color: #ddd;
  opacity: 1;
}

#preview-container.dark #preview-weights {
  border-color: rgba(255,255,255,0.1);
  opacity: 1;
}

.weight-sample {
  display: flex;
  align-items: baseline;
  gap: 16px;
}

.weight-label {
  font-size: 11px;
  opacity: 0.5;
  min-width: 80px;
  text-align: right;
  font-variant-numeric: tabular-nums;
}

.weight-text {
  font-size: 20px;
  line-height: 1.3;
}

/* ---- Scrollbar in sidebar ---- */
#pairs-list::-webkit-scrollbar { width: 14px; }
#pairs-list::-webkit-scrollbar-track { background: var(--sz-color-button-face); }
#pairs-list::-webkit-scrollbar-thumb { background: var(--sz-color-button-shadow); border: 2px solid var(--sz-color-button-face); }
#pairs-list::-webkit-scrollbar-thumb:hover { background: var(--sz-color-gray-text); }

/* ---- Copy feedback ---- */
.copy-flash {
  animation: flash-green 0.6s ease;
}

@keyframes flash-green {
  0% { background: #4caf50; color: #fff; }
  100% { background: var(--sz-color-button-face); color: var(--sz-color-button-text); }
}