:root {
  --bg-primary: #1a1a1a;
  --bg-secondary: #2d2d2d;
  --bg-tertiary: #3a3a3a;
  --text-primary: #e8e8e8;
  --text-secondary: #aaaaaa;
  --accent: #4a9eff;
  --border: #444444;
  --danger: #ff5555;
}

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

body {
  background: var(--bg-primary);
  color: var(--text-primary);
  font-family: 'Segoe UI', system-ui, sans-serif;
  font-size: 13px;
  height: 100vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  user-select: none;
}

/* ── Web / Electron モード切り替え ───────────────── */
body.web-mode .electron-only { display: none !important; }

/* ── Toolbar ─────────────────────────────────────── */
#toolbar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
  flex-wrap: wrap;
}

.toolbar-separator {
  width: 1px;
  height: 20px;
  background: var(--border);
  margin: 0 4px;
}

#folder-path-display {
  color: var(--text-secondary);
  font-size: 12px;
  max-width: 320px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  flex: 1;
}

#image-count {
  color: var(--text-secondary);
  white-space: nowrap;
}

/* ── Controls ────────────────────────────────────── */
button {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 4px 10px;
  cursor: pointer;
  font-size: 13px;
  transition: background 0.15s, border-color 0.15s;
  white-space: nowrap;
}

button:hover:not(:disabled) {
  background: #484848;
  border-color: #666;
}

button:disabled {
  opacity: 0.35;
  cursor: default;
}

button.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

select {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 4px 8px;
  font-size: 13px;
  cursor: pointer;
}

input[type="number"] {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 3px 6px;
  width: 64px;
  font-size: 13px;
}

label {
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 4px;
}

/* ── Drop overlay ────────────────────────────────── */
#drop-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(74, 158, 255, 0.1);
  border: 3px dashed var(--accent);
  z-index: 9999;
  pointer-events: none;
  align-items: center;
  justify-content: center;
}

#drop-overlay.active {
  display: flex;
}

.drop-message {
  color: var(--accent);
  font-size: 22px;
  font-weight: bold;
  background: rgba(26, 26, 26, 0.9);
  padding: 20px 40px;
  border-radius: 8px;
}

/* ── Gallery: Grid view ──────────────────────────── */
#gallery {
  flex: 1;
  overflow-y: auto;
  padding: 12px;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 8px;
  align-content: start;
}

#gallery:empty::before {
  content: 'Easy Pixel Viewer\Aドット絵・スプライトシート向け画像ビューア';
  white-space: pre-wrap;
  color: var(--text-primary);
  font-size: 22px;
  font-weight: bold;
  grid-column: 1 / -1;
  text-align: center;
  padding: 60px 20px 0;
  line-height: 1.8;
}

body.lang-en #gallery:empty::before {
  content: 'Easy Pixel Viewer\AImage viewer for pixel art & sprite sheets';
}

#gallery:empty::after {
  content: '選択したフォルダにある画像ファイル一覧を表示します。フォルダを読み込むと一覧が表示されます。\A\Aフォルダを選択するか、ここにフォルダをドロップしてください';
  white-space: pre-wrap;
  color: var(--text-secondary);
  font-size: 14px;
  grid-column: 1 / -1;
  text-align: center;
  padding: 16px 20px 60px;
  line-height: 2.2;
}

body.lang-en #gallery:empty::after {
  content: 'Shows image files in the selected folder. Load a folder to display the list.\A\ADrop a folder or image file here, or click "Open Folder"';
}

.thumb-item {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  cursor: pointer;
  transition: border-color 0.15s, transform 0.1s;
  display: flex;
  flex-direction: column;
  height: 280px;
}

.thumb-item:hover {
  border-color: var(--accent);
  transform: scale(1.02);
}

.thumb-item img {
  flex: 1;
  min-height: 0;
  width: 100%;
  object-fit: contain;
  background: #111;
  display: block;
}

.thumb-name {
  padding: 4px 6px;
  font-size: 11px;
  color: var(--text-secondary);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  text-align: center;
}

/* ── Gallery: List view ──────────────────────────── */
#gallery.list-view {
  display: flex;
  flex-direction: column;
  gap: 0;
  padding: 0;
}

#gallery.list-view .list-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 5px 14px;
  border-bottom: 1px solid var(--border);
  cursor: pointer;
  transition: background 0.1s;
}

#gallery.list-view .list-item:hover {
  background: var(--bg-secondary);
}

.list-item-name {
  color: var(--text-primary);
  font-size: 13px;
  white-space: nowrap;
  min-width: 180px;
}

.list-item-path {
  color: var(--text-secondary);
  font-size: 11px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  flex: 1;
}

.list-item-size {
  color: var(--text-secondary);
  font-size: 11px;
  white-space: nowrap;
  min-width: 64px;
  text-align: right;
}

/* ── Viewer ──────────────────────────────────────── */
#viewer {
  position: fixed;
  inset: 0;
  background: #1e2022;
  display: flex;
  flex-direction: column;
  z-index: 1000;
}

#viewer.hidden {
  display: none;
}

#viewer-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 6px 12px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
  gap: 8px;
  flex-wrap: wrap;
}

#viewer-filename {
  color: var(--text-primary);
  font-size: 13px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  max-width: 400px;
  flex: 1;
}

#viewer-controls {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

#viewer-canvas-wrap {
  flex: 1;
  position: relative;
  overflow: hidden;
  background: #1e2022;
}

#gif-anim-img {
  position: absolute;
  display: block;
  /* left / top / width / height は JS で動的に設定 */
}
#gif-anim-img.pixel { image-rendering: pixelated; }

#gif-loading {
  position: absolute;
  inset: 0;
  z-index: 20;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 14px;
  background: rgba(20, 20, 20, 0.72);
  pointer-events: none;
}
#gif-loading.hidden { display: none; }

.gif-loading-spinner {
  width: 38px;
  height: 38px;
  border: 3px solid rgba(255,255,255,0.15);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: gif-spin 0.75s linear infinite;
}
.gif-loading-text {
  color: #ccc;
  font-size: 13px;
  letter-spacing: 0.03em;
}
@keyframes gif-spin {
  to { transform: rotate(360deg); }
}

#viewer-canvas-wrap canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

#viewer-canvas  { z-index: 1; }
#grid-canvas    { z-index: 2; pointer-events: none; }
#selection-canvas { z-index: 3; cursor: grab; }
#grid-index-layer { position: absolute; inset: 0; z-index: 4; pointer-events: none; overflow: hidden; }
.grid-index-label {
  position: absolute;
  transform: translate(-100%, -100%);
  font: bold 11px monospace;
  color: #fff;
  background: rgba(0,0,0,0.55);
  padding: 0 2px;
  line-height: 1.3;
  white-space: nowrap;
}

#viewer-statusbar {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 4px 12px;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  color: var(--text-secondary);
  font-size: 12px;
  flex-shrink: 0;
}

/* Prev / Next navigation buttons */
#btn-prev,
#btn-next {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  z-index: 10;
  background: rgba(45, 45, 45, 0.8);
  border: 1px solid var(--border);
  border-radius: 50%;
  width: 44px;
  height: 44px;
  font-size: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  opacity: 0.5;
  transition: opacity 0.2s;
}

#btn-prev { left: 12px; }
#btn-next { right: 12px; }

#btn-prev:hover,
#btn-next:hover {
  opacity: 1;
}

#btn-close-viewer {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-primary);
  font-size: 18px;
  width: 30px;
  height: 30px;
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 4px;
}

#btn-close-viewer:hover {
  background: var(--danger);
  border-color: var(--danger);
}

/* ── Scrollbar ───────────────────────────────────── */
::-webkit-scrollbar       { width: 8px; }
::-webkit-scrollbar-track { background: var(--bg-primary); }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: #666; }

/* ── Grid controls ───────────────────────────────── */
#grid-controls {
  display: flex;
  align-items: center;
  gap: 4px;
  background: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 2px 6px;
  transition: opacity 0.15s;
}

#grid-controls.disabled {
  opacity: 0.35;
  pointer-events: none;
}

#grid-controls input[type="number"] {
  width: 52px;
}

#grid-color {
  width: 28px;
  height: 24px;
  padding: 1px 2px;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--bg-tertiary);
  cursor: pointer;
}

#grid-opacity {
  width: 64px;
  accent-color: var(--accent);
  cursor: pointer;
}

.grid-label {
  color: var(--text-secondary);
  font-size: 12px;
}

/* ── Animation preview panel ─────────────────────── */
#anim-preview {
  position: absolute;
  top: 12px;
  right: 12px;
  width: 280px;
  min-width: 180px;
  min-height: 60px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 8px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.5);
  z-index: 50;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  user-select: none;
}

#anim-preview-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 6px 10px;
  background: var(--bg-tertiary);
  cursor: move;
  font-size: 12px;
  font-weight: bold;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

#anim-preview-header button {
  background: transparent;
  border: none;
  padding: 0 4px;
  font-size: 14px;
  line-height: 1;
  cursor: pointer;
  color: var(--text-secondary);
}

#anim-preview-header button:hover {
  color: var(--text-primary);
  background: transparent;
}

/* Minimized state */
#anim-preview.minimized #anim-preview-body {
  display: none;
}

#anim-preview-body {
  display: flex;
  flex-direction: column;
  flex: 1;
  min-height: 0;
  overflow: hidden;
}

#anim-canvas-wrap {
  background: #111;
  display: flex;
  align-items: center;
  justify-content: center;
  flex: 1;
  min-height: 80px;
  overflow: hidden;
  padding: 8px;
}

#anim-canvas {
  image-rendering: pixelated;
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
}

#anim-frame-info {
  display: flex;
  justify-content: space-between;
  padding: 4px 10px;
  font-size: 11px;
  color: var(--text-secondary);
  border-top: 1px solid var(--border);
  flex-shrink: 0;
}

#anim-index-row {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-top: 1px solid var(--border);
  flex-shrink: 0;
}

#anim-index-input {
  flex: 1;
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 3px 6px;
  font-size: 12px;
  font-family: monospace;
  outline: none;
  min-width: 0;
  transition: border-color 0.15s;
}

#anim-index-input:focus {
  border-color: var(--accent);
}

#anim-index-input.error {
  border-color: var(--danger);
}

#anim-controls {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  padding: 6px 8px;
  flex-shrink: 0;
}

#anim-controls button {
  width: 32px;
  height: 28px;
  padding: 0;
  font-size: 13px;
  display: flex;
  align-items: center;
  justify-content: center;
}

#anim-settings {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 4px 10px 6px;
  font-size: 12px;
  color: var(--text-secondary);
  flex-shrink: 0;
}

#anim-settings input[type="number"] {
  width: 44px;
}

#anim-export-row {
  display: flex;
  gap: 6px;
  margin: 6px 10px 10px;
  flex-shrink: 0;
}

#btn-anim-export {
  flex: 1;
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  font-weight: bold;
}

#btn-anim-export:hover:not(:disabled) {
  background: #6ab4ff;
  border-color: #6ab4ff;
}

#btn-open-output-folder {
  white-space: nowrap;
}

/* Resize handles (added dynamically by JS) */
.anim-resize-handle {
  position: absolute;
  z-index: 20;
  transition: background 0.15s;
}


/* ── GIF Export dialog ───────────────────────────── */
#export-dialog-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.6);
  z-index: 2000;
  display: flex;
  align-items: center;
  justify-content: center;
}

#export-dialog {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 20px 24px;
  min-width: 300px;
  box-shadow: 0 8px 32px rgba(0,0,0,0.6);
}

#export-dialog h3 {
  margin: 0 0 16px;
  font-size: 15px;
  color: var(--text-primary);
}

.export-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 10px;
  gap: 12px;
  font-size: 13px;
  color: var(--text-secondary);
}

.export-row label {
  flex: 1;
  color: var(--text-secondary);
}

.export-row input[type="number"],
.export-row select {
  width: 120px;
}

#export-progress {
  text-align: center;
  padding: 8px;
  color: var(--accent);
  font-size: 13px;
}

.export-buttons {
  display: flex;
  gap: 8px;
  justify-content: flex-end;
  margin-top: 16px;
}

.export-buttons button:first-child {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  font-weight: bold;
}

/* ── Toast ───────────────────────────────────────── */
#toast {
  position: fixed;
  bottom: 48px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(74, 158, 255, 0.92);
  color: #fff;
  padding: 7px 22px;
  border-radius: 20px;
  font-size: 13px;
  opacity: 0;
  transition: opacity 0.25s;
  pointer-events: none;
  z-index: 9999;
  white-space: nowrap;
}

#toast.show { opacity: 1; }

/* ── Search box ──────────────────────────────────── */
#search-box {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 4px 8px;
  font-size: 13px;
  width: 200px;
  outline: none;
  transition: border-color 0.15s;
}

#search-box:focus {
  border-color: var(--accent);
}

#btn-search-clear {
  padding: 4px 7px;
  font-size: 15px;
}

/* ── Utility ─────────────────────────────────────── */
.hidden { display: none !important; }

/* ── Help modal ──────────────────────────────────── */
#help-modal {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.65);
  z-index: 3000;
  display: flex;
  align-items: center;
  justify-content: center;
}

#help-dialog {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 8px;
  width: 680px;
  max-width: 95vw;
  max-height: 85vh;
  display: flex;
  flex-direction: column;
  box-shadow: 0 8px 32px rgba(0,0,0,0.7);
}

#help-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 20px;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

#help-header h2 {
  font-size: 16px;
  color: var(--text-primary);
  margin: 0;
}

#btn-help-close {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-primary);
  font-size: 18px;
  width: 30px;
  height: 30px;
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 4px;
}

#btn-help-close:hover {
  background: var(--danger);
  border-color: var(--danger);
}

#help-body {
  overflow-y: auto;
  padding: 16px 20px;
  flex: 1;
}

#help-intro {
  text-align: center;
  padding: 16px 0 24px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 24px;
}

#help-app-name {
  font-size: 20px;
  font-weight: bold;
  color: var(--text-primary);
  margin-bottom: 8px;
}

#help-app-desc {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.8;
}

#help-app-link {
  margin-top: 8px;
  font-size: 12px;
}

#help-app-link a {
  color: var(--accent);
  text-decoration: none;
}

#help-app-link a:hover {
  text-decoration: underline;
}

.help-section {
  margin-bottom: 24px;
}

.help-section-title {
  font-size: 13px;
  font-weight: bold;
  color: var(--accent);
  margin-bottom: 8px;
  padding-bottom: 5px;
  border-bottom: 1px solid var(--border);
}

.help-dl {
  display: grid;
  grid-template-columns: minmax(120px, max-content) 1fr;
  gap: 2px 16px;
  font-size: 12px;
}

.help-dl dt {
  color: var(--text-primary);
  font-weight: bold;
  padding: 5px 0;
  align-self: start;
}

.help-dl dd {
  color: var(--text-secondary);
  padding: 5px 0;
  margin: 0;
  line-height: 1.65;
}

.shortcut-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 12px;
}

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

.shortcut-table th {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  font-weight: bold;
}

.shortcut-table td {
  color: var(--text-secondary);
}

kbd {
  background: var(--bg-tertiary);
  border: 1px solid #666;
  border-radius: 3px;
  padding: 1px 6px;
  font-family: monospace;
  font-size: 11px;
  color: var(--text-primary);
}

/* Language switch helpers */
.hl-ja, .hl-en { display: none; }
#help-modal.lang-ja .hl-ja { display: inline; }
#help-modal.lang-en .hl-en { display: inline; }

/* ? help buttons */
#btn-help,
#btn-help-viewer {
  font-weight: bold;
  min-width: 26px;
  padding: 4px 8px;
}