:root {
    --ink:      #1a1a2e;
    --ink-2:    #3d3d5c;
    --ink-3:    #8888aa;
    --paper:    #f7f6f2;
    --paper-2:  #eeecea;
    --paper-3:  #e2e0db;
    --gold:     #c9a84c;
    --gold-2:   #e8c96a;
    --danger:   #c0392b;
    --success:  #27ae60;
    --radius:   10px;
    --shadow:   0 2px 16px rgba(26,26,46,0.10);
    --font-display: 'Georgia','Noto Serif SC',serif;
    --font-body: system-ui,-apple-system,'PingFang SC',sans-serif;
  }
  *,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
  html,body{height:100%;overflow:hidden}
  body{background:var(--paper);color:var(--ink);font-family:var(--font-body);font-size:15px;line-height:1.6}
  button{cursor:pointer;font-family:inherit}
  input,textarea{font-family:inherit}

  /* Auth */
  #auth-screen{min-height:100vh;display:flex;align-items:center;justify-content:center;background:var(--ink);padding:24px}
  .auth-card{background:var(--paper);border-radius:16px;padding:48px 40px;width:100%;max-width:400px;box-shadow:0 8px 48px rgba(0,0,0,0.4)}
  .auth-logo{font-family:var(--font-display);font-size:22px;color:var(--ink);margin-bottom:8px;letter-spacing:.02em}
  .auth-logo span{color:var(--gold)}
  .auth-tagline{font-size:13px;color:var(--ink-3);margin-bottom:36px}
  .auth-tabs{display:flex;margin-bottom:28px;border-bottom:2px solid var(--paper-3)}
  .auth-tab{flex:1;padding:10px;text-align:center;font-size:14px;color:var(--ink-3);background:none;border:none;border-bottom:2px solid transparent;margin-bottom:-2px;transition:color .2s,border-color .2s}
  .auth-tab.active{color:var(--ink);border-bottom-color:var(--gold);font-weight:600}
  .form-group{margin-bottom:18px}
  .form-group label{display:block;font-size:13px;color:var(--ink-2);margin-bottom:6px;font-weight:500}
  .form-group input{width:100%;padding:11px 14px;border:1.5px solid var(--paper-3);border-radius:var(--radius);font-size:15px;background:var(--paper);color:var(--ink);outline:none;transition:border-color .2s}
  .form-group input:focus{border-color:var(--gold)}
  .btn-primary{width:100%;padding:12px;background:var(--ink);color:var(--paper);border:none;border-radius:var(--radius);font-size:15px;font-weight:600;letter-spacing:.02em;transition:background .2s,opacity .2s}
  .btn-primary:hover{background:var(--ink-2)}
  .btn-primary:disabled{opacity:.5;cursor:not-allowed}
  .auth-msg{font-size:13px;margin-top:14px;text-align:center;min-height:20px}
  .auth-msg.error{color:var(--danger)}
  .auth-msg.success{color:var(--success)}

  /* App */
  #app{display:none;height:100vh;overflow:hidden}
  #app.visible{display:flex}

  /* Sidebar */
  .sidebar{width:260px;background:var(--ink);color:var(--paper);display:flex;flex-direction:column;flex-shrink:0;height:100vh;overflow:hidden}
  .sidebar-header{padding:24px 20px 16px;border-bottom:1px solid rgba(255,255,255,.08)}
  .logo{font-family:var(--font-display);font-size:16px;letter-spacing:.04em;line-height:1.3}
  .logo span{color:var(--gold)}
  .sidebar-search{padding:14px 16px;border-bottom:1px solid rgba(255,255,255,.08)}
  .sidebar-search input{width:100%;padding:8px 12px;background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.12);border-radius:8px;color:var(--paper);font-size:13px;outline:none}
  .sidebar-search input::placeholder{color:rgba(255,255,255,.35)}
  .sidebar-search input:focus{border-color:var(--gold)}
  .sidebar-nav{flex:1;overflow-y:auto;padding:8px 0}
  .sidebar-nav::-webkit-scrollbar{width:4px}
  .sidebar-nav::-webkit-scrollbar-thumb{background:rgba(255,255,255,.15);border-radius:2px}
  .nav-section{padding:16px 20px 6px;font-size:11px;text-transform:uppercase;letter-spacing:.1em;color:rgba(255,255,255,.3);font-weight:600}
  .nav-item{display:flex;align-items:center;gap:10px;padding:10px 20px;font-size:14px;color:rgba(255,255,255,.65);cursor:pointer;border-left:3px solid transparent;transition:all .15s;white-space:nowrap;overflow:hidden}
  .nav-item:hover{background:rgba(255,255,255,.06);color:var(--paper)}
  .nav-item.active{background:rgba(201,168,76,.12);color:var(--gold-2);border-left-color:var(--gold)}
  .nav-item .count{margin-left:auto;font-size:11px;background:rgba(255,255,255,.1);padding:1px 7px;border-radius:10px;flex-shrink:0}
  .nav-item.active .count{background:rgba(201,168,76,.2)}
  .search-results-list{padding:8px 0}
  .search-result-item{padding:10px 20px;cursor:pointer;border-left:3px solid transparent;transition:all .15s}
  .search-result-item:hover{background:rgba(255,255,255,.06);border-left-color:var(--gold)}
  .search-result-book{font-size:12px;color:var(--gold-2);margin-bottom:4px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
  .search-result-content{font-size:12px;color:rgba(255,255,255,.6);line-height:1.5;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
  .search-empty{padding:20px;text-align:center;font-size:13px;color:rgba(255,255,255,.3)}
  .sidebar-footer{padding:14px 16px;border-top:1px solid rgba(255,255,255,.08);display:flex;flex-direction:column;gap:8px}
  .sidebar-btn{display:flex;align-items:center;gap:8px;padding:8px 12px;background:rgba(255,255,255,.07);border:1px solid rgba(255,255,255,.1);border-radius:8px;color:rgba(255,255,255,.7);font-size:13px;transition:all .15s;width:100%}
  .sidebar-btn:hover{background:rgba(255,255,255,.12);color:var(--paper)}

  /* Main */
  .main{flex:1;display:flex;flex-direction:column;overflow:hidden;background:var(--paper)}
  .topbar{display:flex;border-bottom:1px solid var(--paper-3);background:var(--paper);flex-shrink:0}
  .topbar-title{font-family:var(--font-display);font-size:20px;color:var(--ink);flex:1}
  .topbar-sub{font-size:13px;color:var(--ink-3)}
  .topbar-sub.topbar-book-count-enter{animation:topbar-book-count-enter .16s ease-out}
  @keyframes topbar-book-count-enter{from{opacity:0;transform:translateY(-2px)}to{opacity:1;transform:translateY(0)}}
  .btn-import{display:flex;align-items:center;gap:6px;padding:9px 18px;background:var(--gold);color:var(--ink);border:none;border-radius:var(--radius);font-size:14px;font-weight:600;transition:background .2s}
  .btn-import:hover{background:var(--gold-2)}
  .content-area{flex:1;overflow-y:auto;padding:28px}
  .content-area::-webkit-scrollbar{width:6px}
  .content-area::-webkit-scrollbar-thumb{background:var(--paper-3);border-radius:3px}

  /* Book grid */
  .books-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(180px,1fr));gap:20px}
  .book-card{cursor:pointer;border-radius:var(--radius);overflow:hidden;background:var(--paper-2);transition:transform .2s,box-shadow .2s;border:1px solid var(--paper-3)}
  .book-card:hover{transform:translateY(-3px);box-shadow:var(--shadow)}
  .cover-wrap{position:relative;width:100%;aspect-ratio:2/3;overflow:hidden;background:var(--paper-3)}
  .cover-skeleton{position:absolute;inset:0;background:linear-gradient(90deg,var(--paper-2) 25%,var(--paper-3) 37%,var(--paper-2) 63%);background-size:400% 100%;animation:skeleton-shimmer 1.4s ease infinite}
  @keyframes skeleton-shimmer{0%{background-position:100% 0}100%{background-position:0 0}}
  .cover-wrap .book-cover{position:absolute;inset:0;width:100%;height:100%;aspect-ratio:auto;object-fit:cover;opacity:0;transition:opacity .35s ease;display:block}
  .cover-wrap .book-cover.loaded{opacity:1}
  .book-cover-placeholder{width:100%;aspect-ratio:2/3;display:flex;flex-direction:column;align-items:center;justify-content:center;background:linear-gradient(135deg,var(--ink) 0%,var(--ink-2) 100%);color:var(--paper);padding:16px;text-align:center;gap:8px}
  .book-cover-placeholder .ph-title{font-family:var(--font-display);font-size:13px;line-height:1.4;opacity:.9}
  .book-cover-placeholder .ph-author{font-size:11px;opacity:.5}
  .grid-sentinel{display:flex;justify-content:center;padding:24px 0;width:100%}
  .nav-book-list{display:flex;flex-direction:column}
  .book-info{padding:12px}
  .book-title{font-size:13px;font-weight:600;color:var(--ink);line-height:1.4;margin-bottom:4px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
  .book-author{font-size:11px;color:var(--ink-3);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
  .book-count{font-size:11px;color:var(--gold);margin-top:6px}

  /* Highlights */
  .highlights-list{display:flex;flex-direction:column;gap:16px}
  .highlight-card{background:var(--paper);border:1px solid var(--paper-3);border-radius:var(--radius);padding:20px 22px;position:relative;transition:box-shadow .2s}
  .highlight-card:hover{box-shadow:var(--shadow)}
  .highlight-card::before{content:'';position:absolute;left:0;top:0;bottom:0;width:3px;background:var(--gold);border-radius:3px 0 0 3px}
  .highlight-content{font-family:var(--font-display);font-size:15px;line-height:1.8;color:var(--ink);white-space:pre-wrap}
  .highlight-note{margin-top:12px;padding:10px 14px;background:var(--paper-2);border-radius:8px;border-left:3px solid var(--ink-3)}
  .highlight-note-label{font-size:11px;color:var(--ink-3);font-weight:600;margin-bottom:4px;text-transform:uppercase;letter-spacing:.06em}
  .highlight-note-text{font-size:13px;color:var(--ink-2);line-height:1.7;white-space:pre-wrap}
  .highlight-actions{display:flex;gap:8px;margin-top:14px;justify-content:flex-end}
  .btn-action{display:flex;align-items:center;gap:5px;padding:5px 12px;border:1px solid var(--paper-3);border-radius:6px;background:var(--paper);color:var(--ink-3);font-size:12px;transition:all .15s}
  .btn-action:hover{border-color:var(--gold);color:var(--gold)}
  .btn-action.danger:hover{border-color:var(--danger);color:var(--danger)}

  /* Search-jump highlight pulse */
  .highlight-card.jump-highlight{animation:jump-pulse-bg 1.8s ease-in-out}
  .highlight-card.jump-highlight::before{animation:jump-pulse-bar 1.8s ease-in-out}
  @keyframes jump-pulse-bg{
    0%,100%{background:var(--paper)}
    15%,60%{background:rgba(201,168,76,.16)}
  }
  @keyframes jump-pulse-bar{
    0%,100%{background:var(--gold);width:3px}
    15%,60%{background:var(--gold-2);width:5px}
  }

  /* Edit-save success flash — confirms an in-place edit landed without
     needing a full page refresh (see saveHighlightEdit in modals.js) */
  .highlight-card.card-flash-saved{animation:save-flash-bg 1s ease-out}
  .highlight-card.card-flash-saved::before{animation:save-flash-bar 1s ease-out}
  @keyframes save-flash-bg{
    0%{background:rgba(107,163,104,.16)}
    100%{background:var(--paper)}
  }
  @keyframes save-flash-bar{
    0%{background:#6ba368;width:5px}
    100%{background:var(--gold);width:3px}
  }

  /* Delete collapse-and-fade — see animateCardRemoval in modals.js.
     Height/opacity/margin/padding are all transitioned together so the
     surrounding cards slide up smoothly as the deleted card shrinks
     away, instead of just vanishing and leaving a gap. */
  .highlight-card.card-removing{
    transition:height .28s ease, opacity .22s ease, margin .28s ease, padding .28s ease, border-width .28s ease;
    opacity:0;
    margin-top:0;margin-bottom:0;padding-top:0;padding-bottom:0;
    border-width:0;
  }

  /* Sort controls */
  .sort-bar{display:flex;align-items:center;gap:8px;margin-bottom:20px;flex-wrap:wrap}
  .sort-label{font-size:12px;color:var(--ink-3);flex-shrink:0}
  .sort-btn{padding:4px 12px;border:1px solid var(--paper-3);border-radius:20px;background:var(--paper);color:var(--ink-3);font-size:12px;cursor:pointer;transition:all .15s}
  .sort-btn.active{background:var(--ink);color:var(--paper);border-color:var(--ink)}
  .sort-btn:hover:not(.active){border-color:var(--ink-3);color:var(--ink)}

  /* Author grid */
  .author-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(160px,1fr));gap:16px}
  .author-card{background:var(--paper);border:1px solid var(--paper-3);border-radius:var(--radius);padding:20px 16px;cursor:pointer;transition:box-shadow .2s,transform .2s;text-align:center}
  .author-card:hover{box-shadow:var(--shadow);transform:translateY(-2px)}
  .author-avatar{width:64px;height:64px;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:26px;font-weight:700;color:#fff;margin:0 auto 12px;font-family:var(--font-display)}
  .author-name{font-family:var(--font-display);font-size:15px;color:var(--ink);margin-bottom:4px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
  .author-meta{font-size:12px;color:var(--ink-3)}

  /* Stats panel */
  .stats-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:16px;margin-bottom:28px}
  .stat-card{background:var(--paper);border:1px solid var(--paper-3);border-radius:var(--radius);padding:20px 22px}
  .stat-value{font-family:var(--font-display);font-size:32px;color:var(--ink);margin-bottom:4px;line-height:1}
  .stat-label{font-size:13px;color:var(--ink-3)}
  .stats-section-title{font-family:var(--font-display);font-size:17px;color:var(--ink);margin:24px 0 12px}
  .stats-rank-list{display:flex;flex-direction:column;gap:10px}
  .stats-rank-item{display:flex;align-items:center;gap:12px;padding:12px 16px;background:var(--paper);border:1px solid var(--paper-3);border-radius:var(--radius)}
  .stats-rank-num{font-size:18px;font-weight:700;color:var(--paper-3);width:28px;flex-shrink:0;text-align:center}
  .stats-rank-num.top{color:var(--gold)}
  .stats-rank-name{flex:1;font-size:14px;color:var(--ink);white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
  .stats-rank-count{font-size:13px;color:var(--ink-3);flex-shrink:0}
  .stats-total-chars{font-size:13px;color:var(--ink-3);margin-top:6px}

  /* Empty / loading */
  .empty-state{display:flex;flex-direction:column;align-items:center;justify-content:center;padding:80px 24px;text-align:center;color:var(--ink-3);gap:12px}
  .empty-icon{font-size:48px;opacity:.5}
  .empty-title{font-family:var(--font-display);font-size:18px;color:var(--ink-2)}
  .empty-sub{font-size:14px;max-width:320px}
  .loading{display:flex;align-items:center;justify-content:center;padding:60px;gap:10px;color:var(--ink-3)}
  .spinner{width:20px;height:20px;border:2px solid var(--paper-3);border-top-color:var(--gold);border-radius:50%;animation:spin .7s linear infinite}
  @keyframes spin{to{transform:rotate(360deg)}}

  /* Modal */
  .modal-overlay{position:fixed;inset:0;background:rgba(26,26,46,.6);display:flex;align-items:center;justify-content:center;z-index:100;padding:20px;backdrop-filter:blur(3px);opacity:0;pointer-events:none;transition:opacity .2s}
  .modal-overlay.open{opacity:1;pointer-events:all}
  .modal{background:var(--paper);border-radius:14px;width:100%;max-width:560px;max-height:90vh;display:flex;flex-direction:column;box-shadow:0 20px 80px rgba(0,0,0,.35);transform:translateY(12px);transition:transform .2s}
  .modal-overlay.open .modal{transform:translateY(0)}
  .modal-header{display:flex;align-items:center;justify-content:space-between;padding:20px 24px;border-bottom:1px solid var(--paper-3);flex-shrink:0}
  .modal-title{font-family:var(--font-display);font-size:18px}
  .modal-close{width:32px;height:32px;border:none;background:var(--paper-2);border-radius:50%;color:var(--ink-3);font-size:18px;display:flex;align-items:center;justify-content:center;transition:background .15s}
  .modal-close:hover{background:var(--paper-3);color:var(--ink)}
  .modal-body{padding:24px;overflow-y:auto;flex:1}
  .modal-footer{padding:16px 24px;border-top:1px solid var(--paper-3);display:flex;gap:10px;justify-content:flex-end;flex-shrink:0}
  .btn-secondary{padding:9px 18px;background:var(--paper-2);border:1px solid var(--paper-3);border-radius:var(--radius);font-size:14px;color:var(--ink-2);transition:background .15s}
  .btn-secondary:hover{background:var(--paper-3)}
  .btn-gold{padding:9px 18px;background:var(--gold);border:none;border-radius:var(--radius);font-size:14px;font-weight:600;color:var(--ink);transition:background .15s}
  .btn-gold:hover{background:var(--gold-2)}
  .btn-gold:disabled{opacity:.5;cursor:not-allowed}
  .btn-danger{padding:9px 18px;background:var(--danger);border:none;border-radius:var(--radius);font-size:14px;font-weight:600;color:#fff;transition:opacity .15s}
  .btn-danger:hover{opacity:.85}

  /* Import modal */
  .import-textarea{width:100%;height:280px;padding:14px;border:1.5px solid var(--paper-3);border-radius:var(--radius);font-size:13px;line-height:1.7;color:var(--ink);background:var(--paper);resize:vertical;outline:none;transition:border-color .2s}
  .import-textarea:focus{border-color:var(--gold)}
  .import-hint{font-size:12px;color:var(--ink-3);margin-top:10px;line-height:1.6}
  .import-preview{margin-top:16px;padding:14px;background:var(--paper-2);border-radius:var(--radius);font-size:13px;display:none}
  .import-preview.show{display:block}
  .import-preview .preview-title{font-weight:600;margin-bottom:4px}
  .import-preview .preview-meta{color:var(--ink-3);font-size:12px}
  .import-error{margin-top:12px;padding:12px 14px;background:#fdf2f2;border:1px solid #f5c6c6;border-radius:var(--radius);font-size:13px;color:var(--danger);display:none}
  .import-error.show{display:block}

  /* Edit book modal */
  .edit-field{margin-bottom:16px}
  .edit-field label{display:block;font-size:13px;color:var(--ink-2);margin-bottom:6px;font-weight:500}
  .edit-field input{width:100%;padding:10px 14px;border:1.5px solid var(--paper-3);border-radius:var(--radius);font-size:14px;outline:none;transition:border-color .2s}
  .edit-field input:focus{border-color:var(--gold)}

  /* Cover modal */
  .cover-input-group{display:flex;gap:10px;margin-bottom:14px}
  .cover-input-group input{flex:1;padding:10px 14px;border:1.5px solid var(--paper-3);border-radius:var(--radius);font-size:14px;outline:none}
  .cover-input-group input:focus{border-color:var(--gold)}
  .cover-preview-wrap{width:120px;aspect-ratio:2/3;border-radius:8px;overflow:hidden;border:1px solid var(--paper-3);margin:0 auto;display:block}
  .cover-preview-wrap img{width:100%;height:100%;object-fit:cover;display:block}

  /* Share modal */
  .share-style-row{display:flex;flex-direction:column;gap:10px;margin-bottom:16px}
  .share-style-group{display:flex;align-items:flex-start;gap:10px;width:100%;flex:0 0 auto}
  .share-style-group-label{flex-shrink:0;font-size:11px;color:var(--ink-3);letter-spacing:.5px;width:28px;text-align:right;padding-top:8px}
  /* row-gap set separately from (the shorthand's) column gap: when a
     group's buttons wrap onto a second line, that line sits close to the
     first (row-gap) -- close enough to read as "still the same group" --
     while gap between different groups (.share-style-row's gap, above)
     stays noticeably larger, so which buttons belong together is legible
     at a glance even without re-reading every label. */
  .share-style-group-row{flex:1;min-width:0;display:flex;flex-wrap:wrap;gap:8px;row-gap:6px}
  .share-style-btn{padding:7px 16px;border:1.5px solid var(--paper-3);border-radius:20px;background:var(--paper);color:var(--ink-2);font-size:13px;transition:all .15s}
  .share-style-btn:hover{border-color:var(--ink-3)}
  .share-style-btn.active{background:var(--ink);color:var(--paper);border-color:var(--ink)}
  .share-style-btn.disabled{opacity:.4;cursor:not-allowed}
  .share-style-btn.disabled:hover{border-color:var(--paper-3)}
  .share-preview{width:100%;max-width:420px;margin:0 auto;box-shadow:var(--shadow)}
  .share-toggle-row{display:flex;align-items:center;gap:10px;margin-top:16px;justify-content:center;font-size:13px;color:var(--ink-3)}
  .toggle-switch{position:relative;width:40px;height:22px;flex-shrink:0}
  .toggle-switch input{opacity:0;width:0;height:0}
  .toggle-slider{position:absolute;inset:0;background:var(--paper-3);border-radius:22px;cursor:pointer;transition:.2s}
  .toggle-slider:before{content:'';position:absolute;height:16px;width:16px;left:3px;bottom:3px;background:white;border-radius:50%;transition:.2s}
  .toggle-switch input:checked + .toggle-slider{background:var(--gold)}
  .toggle-switch input:checked + .toggle-slider:before{transform:translateX(18px)}

  /* Back, mobile, toast */
  .back-btn{display:flex;align-items:center;gap:6px;padding:7px 14px;border:1px solid var(--paper-3);border-radius:8px;background:var(--paper);color:var(--ink-3);font-size:13px;transition:all .15s}
  .back-btn:hover{border-color:var(--ink-3);color:var(--ink)}
  .mobile-menu-btn{display:none;width:38px;height:38px;border:1px solid var(--paper-3);border-radius:8px;background:var(--paper);align-items:center;justify-content:center;font-size:18px;color:var(--ink-2)}
  .sidebar-backdrop{display:none;position:fixed;inset:0;background:rgba(0,0,0,.5);z-index:49}
  #toast{position:fixed;bottom:24px;left:50%;transform:translateX(-50%);background:var(--ink);color:var(--paper);padding:10px 20px;border-radius:8px;font-size:13px;opacity:0;pointer-events:none;transition:opacity .3s;z-index:999;white-space:nowrap}
  #toast.show{opacity:1}

  /* Star */
  .btn-action.starred{color:var(--gold);border-color:var(--gold)}
  .btn-action.starred:hover{color:var(--gold-2);border-color:var(--gold-2)}

  /* Tags on highlight card */
  .highlight-tags{display:flex;flex-wrap:wrap;gap:6px;margin-top:10px}
  .tag-chip{display:inline-flex;align-items:center;gap:4px;padding:2px 10px;background:var(--paper-2);border:1px solid var(--paper-3);border-radius:20px;font-size:11px;color:var(--ink-3);cursor:default}
  .tag-chip.removable{cursor:pointer}
  .tag-chip.removable:hover{border-color:var(--danger);color:var(--danger)}

  /* Tag modal */
  .tag-input-row{display:flex;gap:8px;margin-bottom:12px}
  .tag-input-row input{flex:1;padding:8px 12px;border:1.5px solid var(--paper-3);border-radius:8px;font-size:14px;outline:none;transition:border-color .2s}
  .tag-input-row input:focus{border-color:var(--gold)}
  .tag-suggestions-label{font-size:12px;color:var(--ink-3);margin-bottom:8px}
  .tag-suggestions{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:8px;min-height:28px}
  .tag-suggestion{padding:3px 10px;background:var(--paper-2);border:1px solid var(--paper-3);border-radius:20px;font-size:12px;color:var(--ink-3);cursor:pointer;transition:all .15s}
  .tag-suggestion:hover{border-color:var(--gold);color:var(--gold)}
  .tag-divider{border:none;border-top:1px solid var(--paper-3);margin:16px 0}
  .tag-current-label{font-size:12px;color:var(--ink-3);margin-bottom:10px}
  .tag-current{display:flex;flex-wrap:wrap;gap:8px}
  /* Distinguish suggestion chips from current-tag chips */
  .tag-suggestion{background:var(--paper-2);border-color:var(--paper-3);color:var(--ink-3)}
  .tag-chip.removable{background:rgba(201,168,76,.12);border-color:var(--gold);color:var(--ink-2)}
  .tag-chip.removable:hover{background:rgba(192,57,43,.08);border-color:var(--danger);color:var(--danger)}
  /* Category */
  .category-badge{display:inline-flex;align-items:center;gap:4px;padding:3px 10px;background:rgba(61,61,92,.1);border:1px solid rgba(61,61,92,.2);border-radius:20px;font-size:12px;color:var(--ink-2)}
  /* Clickable author name on the book-detail page — a subtle dashed
     underline on hover signals "clickable" without looking like a
     regular hyperlink. */
  .author-link{display:inline-block;cursor:pointer;border-bottom:1px dashed transparent;transition:border-color .15s,color .15s}
  .author-link:hover{border-bottom-color:var(--ink-3);color:var(--ink-2)}
  /* Tag browse */
  .tag-browse-grid{display:flex;flex-wrap:wrap;gap:10px;padding:4px 0}
  .tag-browse-chip{display:inline-flex;align-items:center;gap:6px;padding:8px 16px;background:var(--paper-2);border:1.5px solid var(--paper-3);border-radius:24px;font-size:14px;color:var(--ink-2);cursor:pointer;transition:all .2s}
  .tag-browse-chip:hover{border-color:var(--gold);color:var(--gold);background:rgba(201,168,76,.06)}
  .tag-browse-chip .tag-chip-count{font-size:11px;color:var(--ink-3);background:var(--paper-3);padding:1px 7px;border-radius:10px}
  .category-divider{border:none;border-top:1px dashed var(--paper-3);margin:18px 0}
  .tag-browse-chip.uncategorized{opacity:.7;border-style:dashed}
  .tag-browse-chip.uncategorized:hover{opacity:1}

  /* Topbar */
  .topbar{flex-direction:column;padding:0 !important}
  .topbar-row1{display:flex;align-items:center;gap:10px;padding:14px 28px;width:100%;min-width:0;overflow:hidden}
  .topbar-row2{padding:0 28px 10px;font-size:18px;color:var(--ink);font-family:var(--font-display);white-space:nowrap;overflow:hidden;text-overflow:ellipsis;display:none}
  .topbar-row2.visible{display:block}
  .topbar-title{min-width:0;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;flex:1}
  .topbar-actions{display:flex;align-items:center;gap:10px;flex-shrink:0}

  @media(max-width:768px){
    /* iOS Safari auto-zooms the whole page on focus whenever the focused
       input/textarea/select computes to a font-size under 16px. Forcing
       16px here (mobile only — desktop keeps its normal, tighter sizes)
       fixes the zoom at the root cause instead of disabling pinch-zoom
       via viewport meta, which would be a real accessibility loss.
       !important is needed because a couple of textareas set their
       font-size inline. */
    input, select, textarea { font-size:16px !important; }

    /* While a modal is open (see utils.js: syncModalScrollLock), lock this
       app's two actually-scrollable regions — there's no window/body-level
       scroll to worry about (html,body are overflow:hidden by design
       already). Without this, iOS Safari lets a touch-drag that starts on
       the modal backdrop keep scrolling whichever of these sits underneath
       it. Scoped to mobile only: this is a touch-gesture quirk, not a
       desktop one — a fixed, pointer-events:all overlay already fully
       blocks mouse-wheel/trackpad scroll from reaching anything under it
       on desktop, so there's nothing to fix there. Doing this on desktop
       too was actively harmful: hiding the (layout-space-reserving,
       ::-webkit-scrollbar-styled) content-area scrollbar reflowed the
       highlight cards a few pixels wider the instant a modal opened.
    */
    body.modal-open .content-area,
    body.modal-open .sidebar-nav { overflow:hidden }

    /* 导出备份/从备份恢复 are desktop-oriented file operations (download
       a JSON file, pick a file to upload) that don't make sense in the
       mobile UI, so they're hidden there — desktop keeps them. */
    .backup-btn{display:none}

    .sidebar{position:fixed;left:-100%;top:0;bottom:0;z-index:50;transition:left .25s ease;width:280px}
    .sidebar.open{left:0}
    .mobile-menu-btn{display:flex}
    .content-area{padding:16px}
    .topbar-row1{padding:10px 14px}
    .topbar-row2{padding:0 14px 8px;font-size:15px}
    .topbar-title{font-size:15px}
    .books-grid{grid-template-columns:repeat(auto-fill,minmax(140px,1fr));gap:14px}
    .auth-card{padding:32px 24px}
    .btn-import{padding:7px 12px;font-size:13px}

    /* Five buttons (星标/编辑/标签/分享/删除) in one row is too tight for
       their labels at the desktop size. Instead of just shrinking the
       font (which still risks wrapping on the widest label), each button
       flex-grows to fill an equal share of the row and its label is
       forced to one line — so the row is always exactly full-width and
       never wraps, regardless of label length. */
    .highlight-actions{gap:6px}
    .btn-action{flex:1;justify-content:center;white-space:nowrap;padding:6px 2px;font-size:12px;gap:3px}

    /* Stats: three cards in one row on mobile */
    .stats-grid{grid-template-columns:repeat(3,1fr);gap:8px}
    .stat-card{padding:12px 10px;text-align:center}
    .stat-value{font-size:18px}
    .stat-label{font-size:11px}
  }

  /* Daily pick */
  .daily-pick-wrap{max-width:520px;margin:20px auto 0;display:flex;flex-direction:column;align-items:center;text-align:center}
  .daily-pick-progress{font-size:12px;color:var(--ink-3);letter-spacing:.05em;margin-bottom:16px}
  .daily-pick-card{width:100%;text-align:left;margin-bottom:14px}
  .daily-pick-footer-row{width:100%;display:flex;align-items:center;gap:10px;margin-bottom:28px}
  .daily-pick-meta{font-size:13px;color:var(--ink-3);text-align:left;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
  .daily-pick-next{padding:11px 32px;font-size:15px}
  .daily-pick-actions{display:flex;gap:10px;justify-content:center}
  .daily-pick-prev{padding:11px 24px;font-size:15px}

  /* Celebration */
  .celebration-overlay{position:fixed;inset:0;background:rgba(26,26,46,.55);z-index:999;display:flex;align-items:center;justify-content:center;overflow:hidden}
  .celebration-box{position:relative;z-index:2;background:var(--paper);border-radius:16px;padding:36px 40px;text-align:center;box-shadow:0 20px 80px rgba(0,0,0,.35);max-width:340px;width:calc(100% - 40px)}
  .celebration-emoji{font-size:48px;margin-bottom:14px}
  .celebration-title{font-family:var(--font-display);font-size:19px;font-weight:600;color:var(--ink);margin-bottom:8px}
  .celebration-sub{font-size:13px;color:var(--ink-3);margin-bottom:22px;line-height:1.6}
  .celebration-actions{display:flex;gap:10px;justify-content:center}
  .confetti{position:absolute;top:-20px;border-radius:2px;opacity:.9;animation-name:confetti-fall;animation-timing-function:linear;animation-fill-mode:forwards}
  @keyframes confetti-fall{
    to { transform:translateY(110vh) rotate(360deg); opacity:.15 }
  }
/* ── Manual add book: highlight rows ── */
.manual-highlight-empty{font-size:12px;color:var(--ink-3);padding:12px 0}
.manual-highlight-row{border:1.5px solid var(--paper-3);border-radius:var(--radius);padding:12px;margin-bottom:10px}
.manual-highlight-row-header{display:flex;justify-content:space-between;align-items:center;font-size:12px;color:var(--ink-3);margin-bottom:8px}
.manual-highlight-remove{background:none;border:none;color:var(--danger);font-size:12px;cursor:pointer;padding:0}
.manual-highlight-remove:hover{text-decoration:underline}
.manual-highlight-row input,.manual-highlight-row textarea{width:100%;padding:8px 12px;border:1.5px solid var(--paper-3);border-radius:8px;font-size:13px;outline:none;font-family:inherit;margin-bottom:8px;resize:vertical}
.manual-highlight-row input:focus,.manual-highlight-row textarea:focus{border-color:var(--gold)}
.manual-highlight-row textarea{min-height:56px}
.manual-highlight-row input:last-child,.manual-highlight-row textarea:last-child{margin-bottom:0}

/* ── Restore from backup ── */
.restore-mode-row{display:flex;flex-direction:column;gap:8px}
.restore-mode-option{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--ink-2);cursor:pointer}
.restore-overwrite-warning{margin-top:14px;padding:14px;background:#fdf2f2;border:1px solid #f5c6c6;border-radius:var(--radius)}
.restore-overwrite-warning p{font-size:13px;color:var(--danger);margin-bottom:10px;line-height:1.5}
.restore-overwrite-warning label{display:block;font-size:12px;color:var(--ink-2);margin-bottom:6px}
.restore-overwrite-warning input{width:100%;padding:8px 12px;border:1.5px solid var(--danger);border-radius:8px;font-size:14px;outline:none}
.restore-conflict-item{border:1.5px solid var(--paper-3);border-radius:var(--radius);padding:14px;margin-bottom:10px}
.restore-conflict-title{font-weight:600;font-size:14px;margin-bottom:10px}
.restore-conflict-compare{display:flex;align-items:center;justify-content:center;gap:16px;margin-bottom:12px}
.restore-conflict-side{display:flex;flex-direction:column;align-items:center;gap:6px;width:88px}
.restore-conflict-side-label{font-size:11px;color:var(--ink-3);text-align:center;line-height:1.4}
.restore-conflict-vs{color:var(--ink-3);font-size:14px}
.restore-mini-cover{width:64px;aspect-ratio:2/3;border-radius:6px;overflow:hidden;border:1px solid var(--paper-3);background:var(--paper-2)}
.restore-mini-cover img{width:100%;height:100%;object-fit:cover;display:block}
.restore-mini-cover-placeholder{display:flex;align-items:center;justify-content:center;font-size:22px;background:linear-gradient(135deg,var(--ink) 0%,var(--ink-2) 100%)}
.restore-conflict-choice{display:flex;flex-direction:column;gap:6px;font-size:12px;color:var(--ink-2)}
.restore-conflict-choice label{display:flex;align-items:center;gap:6px;cursor:pointer}

/* ── Add-book choice modal ── */
.add-choice-list{display:flex;flex-direction:column;gap:12px}
.add-choice-item{display:flex;align-items:center;gap:14px;padding:16px;border:1.5px solid var(--paper-3);border-radius:var(--radius);background:var(--paper);text-align:left;cursor:pointer;transition:border-color .2s,background .2s}
.add-choice-item:hover{border-color:var(--gold);background:var(--paper-2)}
.add-choice-icon{font-size:26px;flex-shrink:0}
.add-choice-text{display:flex;flex-direction:column;gap:4px}
.add-choice-text strong{font-size:14px;color:var(--ink)}
.add-choice-text small{font-size:12px;color:var(--ink-3);line-height:1.5}

/* ── WeRead sync ── */
.weread-sync-intro{margin:0 0 14px;font-size:13px;line-height:1.7;color:var(--ink-2)}
.weread-key-link{width:100%;margin-bottom:16px;text-align:left}
.weread-sync-status{min-height:20px;margin-top:14px;font-size:12px;line-height:1.6;color:var(--ink-3)}
.weread-sync-status.weread-sync-error{color:var(--danger)}
.weread-sync-footer{justify-content:space-between}

/* ── Category groups (整理分类) tree editor ── */
.cg-hint{font-size:12px;color:var(--ink-3);line-height:1.6;margin-bottom:16px}
.cg-section{margin-bottom:20px}
.cg-section-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:10px;font-size:13px;font-weight:600;color:var(--ink-2)}
.cg-add-root-btn{padding:5px 12px;font-size:12px}

.cg-tree-area{min-height:64px;border:1.5px dashed var(--paper-3);border-radius:var(--radius);padding:10px;transition:border-color .15s,background .15s}
.cg-empty-hint{font-size:12px;color:var(--ink-3);padding:14px;text-align:center}

.cg-node{position:relative}
.cg-node-row{display:flex;align-items:center;gap:8px;padding:8px 10px;border-radius:8px;cursor:grab;transition:background .15s,box-shadow .15s}
.cg-node-row:hover{background:var(--paper-2)}
.cg-node-row:active{cursor:grabbing}
.cg-node-icon{font-size:13px;flex-shrink:0}
.cg-node-name{font-size:14px;color:var(--ink);flex:1;min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.cg-node-count{font-size:11px;color:var(--gold);flex-shrink:0}
.cg-node-actions{display:flex;gap:2px;flex-shrink:0;opacity:0;transition:opacity .15s}
.cg-node-row:hover .cg-node-actions{opacity:1}
.cg-node-actions button{width:22px;height:22px;border-radius:6px;font-size:12px;color:var(--ink-3);background:transparent;transition:background .15s,color .15s}
.cg-node-actions button:hover{background:var(--paper-3);color:var(--ink)}

/* Drop-position indicators shown during dragover — a thin line above/
   below the row for "insert as sibling here", a highlighted background
   for "nest as a child of this node". */
.cg-node-row.cg-drop-before{box-shadow:0 -2px 0 var(--gold)}
.cg-node-row.cg-drop-after{box-shadow:0 2px 0 var(--gold)}
.cg-node-row.cg-drop-nest{background:rgba(201,168,76,.16);outline:1.5px dashed var(--gold)}

.cg-ungrouped-area{display:flex;flex-wrap:wrap;gap:8px;min-height:48px;border:1.5px dashed transparent;border-radius:var(--radius);padding:8px;transition:border-color .15s,background .15s}
.cg-ungrouped-area.cg-drop-target-active{border-color:var(--gold);background:rgba(201,168,76,.08)}
.cg-pill{display:inline-flex;align-items:center;gap:6px;padding:7px 14px;background:var(--paper-2);border:1.5px solid var(--paper-3);border-radius:20px;font-size:13px;color:var(--ink-2);cursor:grab}
.cg-pill:active{cursor:grabbing}
.cg-pill-count{font-size:11px;color:var(--ink-3)}

/* Category browse page: tree-grouped list vs. the flat ungrouped grid
   below it, plus the entry point into the editor modal. */
.category-browse-header{display:flex;justify-content:flex-end;margin-bottom:14px}
.category-tree-list{margin-bottom:18px}
.category-section-label{font-size:12px;color:var(--ink-3);margin:4px 0 10px;font-weight:600}
.tag-browse-chip.cg-tree-chip{display:flex;width:fit-content;margin-bottom:6px}
.cg-tree-folder-label{font-size:13px;color:var(--ink-3);padding:6px 4px;font-weight:600}
/* A horizontal run of childless siblings at the same tree level —
   siblings with no children of their own share one wrapping row instead
   of each claiming a full line, since there's nothing nested under them
   to make room for. */
.cg-tree-row{margin-bottom:8px}
/* A branch chip (has children) always sits on its own line, immediately
   followed by its children's own row(s) indented further — this margin
   keeps it from crowding whatever line came right before it. */
.tag-browse-chip.cg-tree-branch-chip{margin-bottom:8px}