/* ============================================================
   PDF編集・圧縮ツール 本体スタイル（v9: 制作スタジオ風・1画面アプリシェル）
   - 操作部（ヘッダー・左カラム）はライト、プレビュー作業台だけダーク
   - PC(≥960px)は「ヘッダー＋左=設定/結果＋右=プレビュー」でページスクロールなし
   - <960px は従来どおり縦積み（スマホの操作性を維持）
   ============================================================ */
:root {
  /* ライト側（操作部） */
  --bg: #f2f2f0;
  --surface-1: #f2f2f0;          /* 旧名互換 */
  --surface-2: #ffffff;
  --border: #e3e2de;
  --border-strong: #c9c7c1;
  --text-primary: #1b1c1e;
  --text-secondary: #5c5d5f;
  --text-muted: #8e8f90;
  --accent: #3b74b8;
  --accent-strong: #2e5d99;
  --accent-bg: #eaf1f9;
  --tip-keep: #3f7d52;           /* 無傷・良い数字（緑） */
  --warn-bg: #fdf6e3;
  --warn-border: #e6d9a8;
  --warn-text: #7a5a12;
  --danger-bg: #fbeceb;
  --danger-border: #eab8b4;
  --danger-text: #8a2b22;
  --ok-bg: #eef5ef;
  --ok-border: #cfe0d3;
  --radius: 8px;

  /* ダーク側（プレビュー作業台） */
  --deck: #26282d;
  --deck-well: #1e2024;
  --deck-border: #34373d;
  --deck-ink: #e9eaeb;
  --deck-ink-2: #a2a4a8;
  --deck-good: #85cba0;
  --deck-over: #e0b56a;

  /* 文字サイズ（名前付き4スケール。全テキストはこの4つのいずれかを使う） */
  --fs-title: 15px;  /* Title: アプリ名・タブ */
  --fs-label: 13.5px;/* Label: 操作・ラベル・強調の数字 */
  --fs-body:  12.5px;/* Body/Sub: 本文・説明・注記 */
  --fs-cap:   11px;  /* Caption: バッジ・番号・小見出し */

  /* 派生 */
  --on-accent: #ffffff;
  --overlay: rgba(26,26,24,0.72);
  --shadow-sm:  0 1px 3px rgba(0,0,0,0.05);
  --shadow-key: 0 1px 2px rgba(0,0,0,0.25);
  --shadow-pop: 0 10px 28px rgba(0,0,0,0.20);
  --shadow-paper: 0 12px 34px rgba(0,0,0,0.55), 0 2px 8px rgba(0,0,0,0.4);
}
* { box-sizing: border-box; }
html { height: 100%; }
body {
  height: 100vh; height: 100dvh;
  margin: 0; display: flex; flex-direction: column; overflow: hidden;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Kaku Gothic ProN", "Yu Gothic", sans-serif;
  font-size: var(--fs-body);
  background: var(--bg);
  color: var(--text-primary);
  -webkit-text-size-adjust: 100%;
}

button { font-family: inherit; cursor: pointer; }
button:disabled { cursor: default; }
button:focus-visible, input:focus-visible, select:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* hidden属性の取りこぼし防止（display指定を持つ要素はUAの[hidden]に勝ってしまうため明示） */
[hidden] { display: none !important; }

/* ============ ヘッダーバー ============ */
.bar {
  flex: none; min-height: 52px;
  display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
  padding: 6px 16px; background: var(--surface-2); border-bottom: 1px solid var(--border);
}
.brand { display: flex; align-items: center; gap: 9px; margin-right: 6px; }
.brand h1 { font-size: var(--fs-title); font-weight: 700; letter-spacing: .01em; margin: 0; }
.brand-mark {
  width: 26px; height: 26px; border-radius: 7px; background: var(--accent);
  color: var(--on-accent); display: inline-flex; align-items: center; justify-content: center;
  font-size: 13px; font-weight: 700; flex: none;
}
.file-label {
  display: inline-flex; align-items: center; gap: 7px;
  padding: 8px 14px; border: 1px solid var(--accent);
  border-radius: var(--radius); background: var(--accent); color: var(--on-accent); cursor: pointer;
  font-size: var(--fs-label); font-weight: 600;
}
.file-label:hover { background: var(--accent-strong); border-color: var(--accent-strong); }
.file-label .ico svg, .ghost-btn .ico svg { width: 15px; height: 15px; display: block; }
.ghost-btn {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 8px 12px; font-size: var(--fs-body); color: var(--text-secondary);
  border: none; background: none; border-radius: var(--radius);
}
.ghost-btn:hover:not(:disabled) { background: var(--bg); color: var(--text-primary); }
.ghost-btn:disabled { opacity: .45; }
.status-text { font-size: var(--fs-body); color: var(--text-secondary); }
.bar .status-text { flex: 1 1 120px; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* タブ（セグメント型） */
.tabs { margin-left: auto; display: flex; background: #e7e7e4; border-radius: 10px; padding: 3px; gap: 2px; flex: none; }
.tab {
  border: none; background: none; padding: 7px 16px; border-radius: 8px;
  font-size: var(--fs-label); font-weight: 600; color: var(--text-secondary);
}
.tab:hover { color: var(--text-primary); }
.tab.active { background: var(--surface-2); color: var(--text-primary); box-shadow: 0 1px 3px rgba(0,0,0,.14); }
.tab-count {
  display: inline-block; min-width: 17px; padding: 1px 5px; margin-left: 5px;
  border-radius: 999px; background: var(--accent-bg); color: var(--accent-strong);
  font-size: var(--fs-cap); font-weight: 700;
}

/* ============ 上限超過バナー（要件§9） ============ */
.banner {
  flex: none; padding: 8px 16px; font-size: var(--fs-body); line-height: 1.55;
}
.banner.warn   { background: var(--warn-bg);   border-bottom: 1px solid var(--warn-border);   color: var(--warn-text); }
.banner.danger { background: var(--danger-bg); border-bottom: 1px solid var(--danger-border); color: var(--danger-text); }

/* ============ シェル＋タブパネル ============ */
.shell { flex: 1 1 auto; min-height: 0; }
.view-export { display: grid; grid-template-columns: 390px 1fr; height: 100%; }
.view-pages { height: 100%; overflow-y: auto; padding: 16px 22px; }

/* ============ 左カラム: 設定＋結果 ============ */
.side {
  background: var(--surface-2); border-right: 1px solid var(--border);
  padding: 12px 18px 16px; overflow-y: auto; min-height: 0;
}
.section-head { display: flex; align-items: center; gap: 8px; margin: 0 0 10px; }
.section-title {
  font-size: var(--fs-cap); font-weight: 700; color: var(--text-muted);
  letter-spacing: .1em; margin: 0;
}
.divider { border: none; border-top: 1px solid var(--border); margin: 12px 0; }

.setting-row { margin-bottom: 12px; }
.setting-row:last-of-type { margin-bottom: 0; }
.setting-label {
  display: flex; align-items: center; justify-content: space-between;
  gap: 12px; font-size: var(--fs-label); font-weight: 600; color: var(--text-primary);
  min-height: 28px;
}
label.setting-label { cursor: pointer; }
.setting-label .label-main { display: inline-flex; align-items: center; gap: 8px; min-width: 0; }
.label-toggle { cursor: pointer; }

/* ？ヘルプボタン（丸型・控えめ→ホバー/フォーカスでアクセント） */
.help-btn {
  flex: none; width: 18px; height: 18px; padding: 0; border-radius: 50%;
  border: 1px solid var(--border-strong); background: none;
  color: var(--text-muted); font-size: 10px; font-weight: 700; line-height: 1;
  display: inline-flex; align-items: center; justify-content: center;
  transition: color .12s, border-color .12s, background .12s;
}
.help-btn:hover, .help-btn:focus-visible { color: var(--accent); border-color: var(--accent); background: var(--accent-bg); }

/* 画質: プリセットchip */
.preset-chips { display: flex; flex-wrap: wrap; align-items: center; gap: 6px; margin: 8px 0 2px; }
.chip {
  padding: 6px 13px; border-radius: 999px; border: 1px solid var(--border-strong);
  background: var(--surface-2); color: var(--text-secondary);
  font-size: var(--fs-body); font-weight: 600; transition: color .12s, border-color .12s, background .12s;
}
.chip:hover { border-color: var(--accent); color: var(--accent-strong); }
.chip.selected { background: var(--accent-bg); border-color: var(--accent); color: var(--accent-strong); box-shadow: inset 0 0 0 1px var(--accent); }
.chip-custom { margin-left: auto; font-size: var(--fs-cap); color: var(--text-muted); }
.chip-custom.active { color: var(--accent-strong); font-weight: 700; }

/* スライダー（解像度・JPEG品質・表示倍率で共用） */
.slider-row { margin: 11px 0 0; }
.slider-head { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; }
.slider-name { font-size: var(--fs-body); font-weight: 600; color: var(--text-primary); }
.slider-sub { font-size: var(--fs-cap); font-weight: 400; color: var(--text-muted); margin-left: 7px; }
.slider-val { font-size: var(--fs-label); font-weight: 700; color: var(--accent-strong); font-variant-numeric: tabular-nums; }
input[type=range].slider {
  -webkit-appearance: none; appearance: none; width: 100%; height: 5px; margin: 9px 0 0;
  border-radius: 999px; background: var(--border); cursor: pointer;
}
input[type=range].slider:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }
input[type=range].slider::-webkit-slider-thumb {
  -webkit-appearance: none; appearance: none; width: 19px; height: 19px; border-radius: 50%;
  background: var(--surface-2); border: 2px solid var(--accent); box-shadow: var(--shadow-key); cursor: pointer; margin-top: -7px;
}
input[type=range].slider::-moz-range-thumb {
  width: 17px; height: 17px; border-radius: 50%; background: var(--surface-2);
  border: 2px solid var(--accent); box-shadow: var(--shadow-key); cursor: pointer;
}
input[type=range].slider::-moz-range-track { height: 5px; border-radius: 999px; background: var(--border); }
.quality-textnote { font-size: var(--fs-cap); color: var(--tip-keep); margin: 9px 2px 0; line-height: 1.5; }

/* トグル（スイッチ型） */
.toggle { position: relative; display: inline-flex; align-items: center; flex: none; }
.toggle input {
  position: absolute; top: 0; left: 0; width: 40px; height: 24px;
  margin: 0; opacity: 0; cursor: pointer;
}
.toggle .track {
  width: 40px; height: 24px; border-radius: 999px; background: var(--border-strong);
  transition: background .15s; position: relative; flex: none; pointer-events: none;
}
.toggle .track::after {
  content: ''; position: absolute; top: 3px; left: 3px; width: 18px; height: 18px;
  border-radius: 50%; background: var(--on-accent); transition: transform .15s;
  box-shadow: var(--shadow-key);
}
.toggle input:checked + .track { background: var(--accent); }
.toggle input:checked + .track::after { transform: translateX(16px); }
.toggle input:focus-visible + .track { outline: 2px solid var(--accent); outline-offset: 2px; }

/* 安全警告（常時表示4件） */
.raster-note {
  font-size: var(--fs-body); color: var(--warn-text); background: var(--warn-bg);
  border: 1px solid var(--warn-border); border-radius: 6px;
  padding: 8px 10px; margin: .6rem 0 0; line-height: 1.5;
}
.tips-extra-warn {
  margin-top: 8px; padding-top: 7px; border-top: 1px dashed var(--warn-border);
  color: var(--danger-text); font-weight: 600; font-size: var(--fs-body); line-height: 1.5;
}
/* 強力圧縮の従属サブ項目（画像化ONのときだけ表示） */
.raster-suboption {
  margin-top: .6rem; margin-left: 12px;
  padding-left: 12px; border-left: 2px solid var(--border);
}
.raster-suboption .setting-label { font-weight: 500; }

/* 書き出しアクション + 進捗 */
.export-actions { margin-top: 2px; }
.export-btn {
  width: 100%; justify-content: center; padding: 11px 18px; font-size: 14px; font-weight: 700;
}
.primary-btn {
  display: inline-flex; align-items: center; gap: 7px;
  padding: 9px 16px; font-size: var(--fs-label); font-weight: 600;
  border: 1px solid var(--border-strong); border-radius: var(--radius);
  background: var(--surface-2); color: var(--text-primary);
}
.primary-btn svg { width: 16px; height: 16px; }
.btn-accent { background: var(--accent); color: var(--on-accent); border-color: var(--accent); }
.btn-accent:hover:not(:disabled) { background: var(--accent-strong); border-color: var(--accent-strong); }
.btn-accent:disabled { opacity: 0.45; }
.page-count { display: block; text-align: center; font-size: var(--fs-cap); color: var(--text-muted); margin-top: 7px; }
.progress-wrap { margin-top: 10px; }
.progress-track { height: 6px; border-radius: 999px; background: var(--border); overflow: hidden; }
.progress-bar { height: 100%; width: 0%; background: var(--accent); transition: width .2s ease; }
.progress-text { font-size: var(--fs-body); color: var(--text-secondary); margin-top: 5px; }

/* ============ 書き出し結果（左カラム下部） ============ */
.results {
  margin-top: 14px; border: 1px solid var(--border); border-left: 3px solid var(--tip-keep);
  border-radius: var(--radius); padding: 11px 13px; background: #fbfcfb;
}
.results-title { margin-bottom: 8px; }
.result-size { font-size: var(--fs-label); font-weight: 700; font-variant-numeric: tabular-nums; }
.result-reduce-line { font-size: var(--fs-body); color: var(--text-secondary); margin-top: 3px; }
.result-reduce { color: var(--tip-keep); font-weight: 700; }
.lock-note {
  font-size: var(--fs-body); border-radius: 6px; border: 1px solid;
  padding: 8px 10px; margin: .6rem 0 0; line-height: 1.5;
}
.lock-note.ok { color: var(--tip-keep); background: var(--ok-bg); border-color: var(--ok-border); }
.lock-note.fail { color: var(--danger-text); background: var(--danger-bg); border-color: var(--danger-border); }
.filename-row { display: flex; align-items: center; gap: 7px; margin: 10px 0 0; }
.fn-label { flex: none; font-size: var(--fs-body); color: var(--text-secondary); }
.filename-row input {
  flex: 1; min-width: 80px; padding: 8px 10px; font: inherit; font-size: var(--fs-label);
  border: 1px solid var(--border-strong); border-radius: 6px;
  background: var(--bg); color: var(--text-primary);
}
.fn-ext { flex: none; font-size: var(--fs-label); color: var(--text-muted); }
.results-actions { display: flex; flex-direction: column; align-items: stretch; gap: 4px; margin-top: 10px; }
.results-actions .btn-accent { justify-content: center; }
.preview-toggle {
  background: none; border: none; color: var(--accent); font-size: var(--fs-body);
  padding: 6px 0; display: inline-flex; align-items: center; gap: 6px; cursor: pointer;
}
.preview-toggle:hover { background: none; text-decoration: underline; }
.pv-caret { display: inline-block; transition: transform .15s; }
.preview-toggle[aria-expanded="true"] .pv-caret { transform: rotate(90deg); }
.preview-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(90px, 1fr));
  gap: 8px; margin-top: .6rem;
}
.preview-cell { position: relative; }
.preview-cell img { width: 100%; display: block; border: 1px solid var(--border); border-radius: 4px; background: #fff; }
.preview-num {
  position: absolute; left: 5px; bottom: 5px; background: var(--overlay);
  color: var(--on-accent); font-size: var(--fs-cap); line-height: 1; padding: 3px 7px; border-radius: 999px;
}
.preview-loading { color: var(--text-muted); font-size: var(--fs-body); padding: .5rem 0; }

/* ============ 右カラム: プレビュー作業台（ダーク） ============ */
.deck {
  background: radial-gradient(120% 90% at 50% 0%, #2c2f35 0%, var(--deck) 55%);
  display: flex; flex-direction: column; min-width: 0; min-height: 0;
}
.preview-tune { flex: 1; display: flex; flex-direction: column; min-height: 0; }
.deck-empty {
  flex: 1; display: none; align-items: center; justify-content: center; text-align: center;
  color: var(--deck-ink-2); font-size: var(--fs-label); padding: 2rem; line-height: 1.8;
}
.preview-tune[hidden] + .deck-empty { display: flex; }

.deck-bar { display: flex; align-items: center; gap: 11px; padding: 10px 18px; color: var(--deck-ink-2); font-size: var(--fs-body); flex-wrap: wrap; }
.pv-sample-label, .pv-zoom-label { font-size: var(--fs-body); color: var(--deck-ink-2); }
.deck-bar select {
  padding: 6px 10px; font: inherit; font-size: var(--fs-body);
  border: 1px solid #43464d; border-radius: 7px;
  background: #33363c; color: var(--deck-ink);
}
input[type=range].pv-zoom { flex: 0 1 140px; min-width: 100px; margin: 0; background: #43464d; }
input[type=range].pv-zoom::-moz-range-track { background: #43464d; }
.pv-zoom-val { font-size: var(--fs-body); font-weight: 700; color: var(--deck-ink); font-variant-numeric: tabular-nums; min-width: 40px; }
.pv-fit-btn {
  flex: none; padding: 4px 12px; border-radius: 999px; border: 1px solid #4a4d54;
  background: none; color: var(--deck-ink-2); font-size: var(--fs-cap); font-weight: 600;
}
.pv-fit-btn:hover, .pv-fit-btn:focus-visible { border-color: var(--deck-ink-2); color: var(--deck-ink); }
.deck-help { margin-left: auto; border-color: #4a4d54; color: var(--deck-ink-2); background: none; }
.deck-help:hover, .deck-help:focus-visible { color: var(--deck-ink); border-color: var(--deck-ink-2); background: none; }

.pv-split { flex: 1; display: grid; grid-template-columns: 1fr 1fr; gap: 16px; padding: 0 18px; min-height: 0; }
.pv-pane { margin: 0; min-width: 0; min-height: 0; display: flex; flex-direction: column; }
.pv-cap-title { font-size: var(--fs-cap); font-weight: 700; color: var(--deck-ink); margin-bottom: 6px; letter-spacing: .08em; }
.pv-cap-cfg { font-weight: 400; color: var(--deck-ink-2); letter-spacing: 0; }
.pv-imgwrap {
  flex: 1; min-height: 0; background: var(--deck-well); border: 1px solid var(--deck-border); border-radius: 10px;
  padding: 14px; overflow: auto; cursor: grab;
  transition: opacity .12s; overscroll-behavior: contain;
}
.pv-imgwrap.grabbing { cursor: grabbing; }
/* pointer-events:none で画像自身のネイティブなドラッグ（ゴースト画像）を無効化し、パン操作を枠が受け取る */
.pv-imgwrap img { display: block; height: auto; max-width: none; background: #fff; box-shadow: var(--shadow-paper); user-select: none; -webkit-user-drag: none; pointer-events: none; }
.pv-imgwrap.loading { opacity: .5; }
.pv-imgwrap .pv-empty { color: var(--deck-ink-2); font-size: var(--fs-body); padding: 1.5rem 0; }

/* プレビュー生成中の進捗（読み込み中/変換中・v10）。スクロールに追従しないよう pv-pane 基準で重ねる */
.pv-pane { position: relative; }
.pv-progress {
  position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%);
  display: flex; flex-direction: column; align-items: center; gap: 7px;
  background: var(--overlay); color: var(--on-accent);
  padding: 10px 16px; border-radius: 8px; pointer-events: none;
}
.pv-progress[hidden] { display: none; }
.pv-progress-label { font-size: var(--fs-cap); line-height: 1; white-space: nowrap; }
.pv-progress-track { display: block; width: 130px; height: 4px; border-radius: 999px; background: rgba(255,255,255,.25); overflow: hidden; }
.pv-progress-fill { display: block; height: 100%; width: 0; border-radius: 999px; background: #fff; transition: width .15s ease; }
.pv-progress.indeterminate .pv-progress-fill { width: 40%; transition: none; animation: pv-indet 1.1s ease-in-out infinite; }
@keyframes pv-indet { from { margin-left: -40%; } to { margin-left: 100%; } }
@media (prefers-reduced-motion: reduce) {
  .pv-progress.indeterminate .pv-progress-fill { animation: none; }
  .pv-progress-fill { transition: none; }
}

/* 容量目安（見せ場: 大きな数字＋メーター） */
.deck-foot { flex: none; padding: 10px 18px 13px; color: var(--deck-ink-2); }
.pv-estimate { display: flex; align-items: baseline; gap: 12px; flex-wrap: wrap; font-size: var(--fs-body); line-height: 1.5; }
.pv-from { font-size: var(--fs-label); color: var(--deck-ink); font-variant-numeric: tabular-nums; }
.pv-arrow { color: var(--deck-ink-2); }
.pv-to-label { font-size: var(--fs-cap); }
.pv-to { font-size: 20px; font-weight: 800; font-variant-numeric: tabular-nums; line-height: 1.1; }
.pv-pct { font-size: var(--fs-label); font-weight: 700; }
.pv-estimate .good { color: var(--deck-good); }
.pv-estimate .over { color: var(--deck-over); }
.pv-meter { display: block; flex: 1 0 100%; height: 6px; border-radius: 999px; background: #3a3d43; overflow: hidden; margin-top: 2px; }
.pv-meter-fill { display: block; height: 100%; border-radius: 999px; background: linear-gradient(90deg, #6fbc8d, #8fd3a9); }
.pv-meter-fill.over { background: linear-gradient(90deg, #c9973f, #e0b56a); }
.pv-est-detail { flex: 1 0 100%; font-size: var(--fs-cap); color: var(--deck-ink-2); }
.pv-note { font-size: var(--fs-cap); color: var(--deck-ink-2); margin: 6px 0 0; line-height: 1.5; }

/* ============ タブ2: ページ編集 ============ */
.pages-hint { color: var(--text-muted); font-size: var(--fs-body); margin: 0 0 14px; line-height: 1.6; }
.empty-hint {
  border: 1px dashed var(--border-strong); border-radius: var(--radius);
  padding: 2.5rem 1rem; text-align: center; color: var(--text-muted); font-size: var(--fs-body);
}
#grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: 13px;
}
.page-card {
  position: relative;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 6px;
  display: flex; flex-direction: column; gap: 6px;
  box-shadow: var(--shadow-sm);
}
.page-card.dragging { opacity: 0.3; }
.card-head {
  display: flex; align-items: center; justify-content: space-between; gap: 4px; min-height: 24px;
}
.fname {
  font-size: var(--fs-cap); color: var(--text-muted);
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
.thumb-wrap { position: relative; }
.thumb-wrap img {
  width: 100%; display: block; border-radius: 4px; border: 1px solid var(--border);
  transition: transform .15s ease; background: #fff;
}
.thumb-placeholder {
  width: 100%; aspect-ratio: 0.72; background: var(--bg); border-radius: 4px;
}
.page-badge {
  position: absolute; left: 5px; bottom: 5px;
  background: var(--overlay); color: var(--on-accent);
  font-size: var(--fs-cap); line-height: 1; padding: 3px 7px; border-radius: 999px;
}
.card-foot {
  display: flex; align-items: center; justify-content: space-between;
  gap: 4px; flex-wrap: wrap; row-gap: 4px;
}
.btn-group { display: inline-flex; gap: 3px; }
.icon-btn {
  display: inline-flex; align-items: center; justify-content: center;
  width: 28px; height: 28px; padding: 0; flex: none;
  border: 1px solid var(--border-strong); border-radius: 6px;
  background: var(--surface-2); color: var(--text-secondary);
}
.icon-btn:hover:not(:disabled) { background: var(--bg); color: var(--text-primary); }
.icon-btn:disabled { opacity: 0.3; }
.icon-btn svg { width: 15px; height: 15px; }
.drag-handle {
  touch-action: none; cursor: grab; color: var(--text-muted);
  display: inline-flex; align-items: center; justify-content: center;
  width: 28px; height: 28px; border-radius: 6px; flex: none;
  -webkit-user-select: none; user-select: none;
}
.drag-handle:hover { background: var(--bg); color: var(--text-secondary); }
.drag-handle:active { cursor: grabbing; }
.drag-handle svg { width: 18px; height: 18px; }
.drag-ghost {
  position: fixed; z-index: 1000; margin: 0; pointer-events: none;
  opacity: 0.92; box-shadow: var(--shadow-pop);
  background: var(--surface-2); border: 1px solid var(--border-strong);
  border-radius: var(--radius);
}

/* ============ ？ポップアップ（ネイティブ<dialog>） ============ */
dialog.help-pop {
  max-width: 460px; width: calc(100% - 32px); border: 1px solid var(--border-strong);
  border-radius: var(--radius); padding: 0; background: var(--surface-2); color: var(--text-primary);
  box-shadow: var(--shadow-pop);
}
dialog.help-pop::backdrop { background: var(--overlay); }
.help-pop-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 14px 16px; border-bottom: 1px solid var(--border); }
.help-pop-title { font-size: var(--fs-label); font-weight: 700; }
.help-pop-close { flex: none; width: 30px; height: 30px; border-radius: 6px; border: 1px solid var(--border); background: var(--bg); color: var(--text-secondary); font-size: 16px; line-height: 1; cursor: pointer; }
.help-pop-close:hover { background: var(--surface-2); border-color: var(--border-strong); }
.help-pop-body { padding: 14px 16px; font-size: var(--fs-body); line-height: 1.6; }
.help-pop-body p { margin: 0 0 .7em; }
.help-pop-body p:last-child { margin-bottom: 0; }
.help-pop-body ul { margin: 0; padding-left: 1.2em; }
.help-pop-body li { margin-bottom: .35em; }

/* ============ レスポンシブ ============ */
/* <960px: 1画面固定をやめて従来どおり縦積み（スマホの操作性を維持） */
@media (max-width: 959px) {
  body { height: auto; min-height: 100vh; overflow: auto; display: block; }
  .shell { min-height: 0; }
  .view-export { display: block; height: auto; }
  .side { border-right: none; border-bottom: 1px solid var(--border); overflow: visible; }
  .deck { min-height: 0; }
  .preview-tune { display: block; }
  .pv-split { display: grid; grid-template-columns: 1fr 1fr; padding: 0 14px; }
  .pv-imgwrap { height: 52vh; flex: none; }
  .view-pages { height: auto; overflow: visible; }
  .deck-empty { padding: 3rem 1.5rem; }
  .preview-tune[hidden] + .deck-empty { display: flex; }
}
@media (max-width: 600px) {
  .pv-split { grid-template-columns: 1fr; }
  .pv-imgwrap { height: 62vh; }
  .tabs { margin-left: 0; width: 100%; }
  .tab { flex: 1; }
}

@media (prefers-reduced-motion: reduce) {
  .toggle .track, .toggle .track::after, .progress-bar, .pv-caret, .thumb-wrap img { transition: none; }
}