:root{--bg-color:#f5f2ea;--panel-bg:#fffdf8;--border-color:#ddd6c7;--text-primary:#141713;--text-secondary:#5d635b;--accent-color:#16785f;--accent-hover:#0f604c;--danger-color:#dc2626;--canvas-bg:#e6e1d7;--hover-bg:#0000000d;color:var(--text-primary);background-color:var(--bg-color);font-family:system-ui,-apple-system,sans-serif;line-height:1.5}@media (prefers-color-scheme:dark){:root{--bg-color:#071013;--panel-bg:#0d1715;--border-color:#22332f;--text-primary:#f5fff9;--text-secondary:#a2b2aa;--accent-color:#64f4c4;--accent-hover:#9fffe0;--canvas-bg:#101819;--hover-bg:#ffffff0d}}*{box-sizing:border-box;margin:0;padding:0}body{margin:0;font-size:14px}.app{flex-direction:column;height:100vh;display:flex;overflow:hidden}.app-header{background:color-mix(in srgb, var(--panel-bg) 92%, transparent);border-bottom:1px solid var(--border-color);-webkit-backdrop-filter:blur(16px);backdrop-filter:blur(16px);flex-shrink:0;justify-content:space-between;align-items:center;gap:16px;padding:12px 18px;display:flex}h1{font-size:18px;font-weight:600}.brand-row{align-items:center;min-width:0;display:flex}.brand-link{color:var(--text-primary);align-items:center;gap:10px;text-decoration:none;display:inline-flex}.brand-mark{color:#64f4c4;letter-spacing:0;background:linear-gradient(135deg,#071013,#102623 54%,#261a3d);border-radius:8px;place-items:center;width:36px;height:36px;font-size:13px;font-weight:900;display:grid;box-shadow:0 12px 30px #16785f38}.brand-copy{flex-direction:column;line-height:1.05;display:flex}.eyebrow{color:var(--text-secondary);text-transform:uppercase;letter-spacing:.13em;font-size:10px;font-weight:800}.title-line{margin-top:3px;font-size:17px;font-weight:750}.header-tabs{gap:8px;margin-left:24px;display:flex}.tab-btn{color:var(--text-secondary);cursor:pointer;background:0 0;border:none;border-radius:4px;align-items:center;gap:6px;padding:6px 12px;font-size:13px;font-weight:500;transition:all .2s;display:inline-flex}.tab-btn:hover{color:var(--text-primary);background-color:var(--hover-bg)}.tab-btn.active{color:var(--accent-color);background-color:#3b82f61a;font-weight:600}.main-layout{flex:1;display:flex;overflow:hidden}.sidebar{background-color:var(--panel-bg);border-right:1px solid var(--border-color);flex-direction:column;flex-shrink:0;gap:20px;width:320px;padding:20px;display:flex;overflow-y:auto}.workspace{background-color:var(--canvas-bg);flex-direction:column;flex:1;display:flex;position:relative;overflow:hidden}.toolbar{background-color:var(--panel-bg);border-bottom:1px solid var(--border-color);flex-shrink:0;justify-content:space-between;align-items:center;padding:8px 16px;display:flex}.viewport{flex:1;justify-content:center;align-items:center;padding:24px;display:flex;overflow:auto}.crop-wrapper{background-color:#fff;border-radius:2px;position:relative;box-shadow:0 4px 12px #00000026}.crop-overlay{cursor:crosshair;z-index:10;width:100%;height:100%;position:absolute;top:0;left:0}.crop-rect{fill:#0000;stroke:var(--accent-color);stroke-width:2px;cursor:move}.crop-shroud{fill:#0006}.handle{fill:#fff;stroke:var(--accent-color);stroke-width:2px}.handle:hover{fill:var(--accent-color)}.file-drop{border:2px dashed var(--border-color);text-align:center;cursor:pointer;color:var(--text-secondary);background:linear-gradient(180deg, color-mix(in srgb, var(--panel-bg) 92%, var(--accent-color)), var(--panel-bg));border-radius:8px;padding:30px 14px;transition:border-color .2s,transform .2s,box-shadow .2s}.file-drop:hover{border-color:var(--accent-color);transform:translateY(-1px);box-shadow:0 18px 42px #00000014}.btn{cursor:pointer;border:1px solid #0000;border-radius:6px;justify-content:center;align-items:center;padding:8px 16px;font-size:13px;font-weight:500;transition:background-color .2s,border-color .2s;display:inline-flex}.btn-primary{background-color:var(--accent-color);color:#06110f}.btn-primary:hover:not(:disabled){background-color:var(--accent-hover)}.btn-secondary{border-color:var(--border-color);color:var(--text-secondary);background-color:#0000}.btn-secondary:hover:not(:disabled){background-color:var(--hover-bg);color:var(--text-primary)}.btn:disabled{opacity:.5;cursor:not-allowed}.form-group{flex-direction:column;gap:6px;display:flex}label{color:var(--text-secondary);font-size:12px;font-weight:600}.input{border:1px solid var(--border-color);background-color:var(--panel-bg);color:var(--text-primary);border-radius:4px;outline:none;padding:8px 12px}.input:focus{border-color:var(--accent-color)}.grid-2{grid-template-columns:1fr 1fr;gap:10px;display:grid}.pages-grid{border:1px solid var(--border-color);border-radius:4px;grid-template-columns:repeat(auto-fill,minmax(60px,1fr));gap:8px;max-height:150px;padding:8px;display:grid;overflow-y:auto}.page-thumb-btn{aspect-ratio:1/1.4;background-color:var(--bg-color);border:1px solid var(--border-color);cursor:pointer;color:var(--text-secondary);border-radius:3px;justify-content:center;align-items:center;font-size:11px;font-weight:700;display:flex}.page-thumb-btn.active{border-color:var(--accent-color);color:var(--accent-color);background-color:#3b82f61a}.spinner{border:2px solid #ffffff4d;border-top-color:#fff;border-radius:50%;width:16px;height:16px;animation:.8s linear infinite spin}@keyframes spin{to{transform:rotate(360deg)}}.status-bar{background-color:var(--panel-bg);border-top:1px solid var(--border-color);color:var(--text-secondary);padding:6px 12px;font-size:12px}.empty-state{text-align:center;width:min(680px,100%);color:var(--text-secondary);padding:24px}.empty-state img{image-rendering:auto;width:min(220px,70vw);height:auto;margin-bottom:18px}.empty-state h2{color:var(--text-primary);margin-bottom:12px;font-size:clamp(24px,4vw,42px);line-height:1}.empty-state p{max-width:540px;margin:0 auto;font-size:15px;line-height:1.7}.merge-viewport{flex:1;justify-content:center;align-items:flex-start;padding:40px 24px;display:flex;overflow-y:auto}.merge-card{background-color:var(--panel-bg);border:1px solid var(--border-color);border-radius:8px;flex-direction:column;gap:20px;width:100%;max-width:640px;padding:24px;display:flex;box-shadow:0 4px 12px #0000000d}.merge-file-list{border:1px solid var(--border-color);background-color:var(--bg-color);border-radius:6px;flex-direction:column;gap:8px;max-height:380px;padding:8px;display:flex;overflow-y:auto}.merge-file-item{background-color:var(--panel-bg);border:1px solid var(--border-color);border-radius:6px;justify-content:space-between;align-items:center;gap:12px;padding:10px 14px;display:flex}.file-info{flex-direction:column;flex:1;gap:2px;min-width:0;display:flex}.file-name{text-overflow:ellipsis;white-space:nowrap;color:var(--text-primary);font-size:13px;font-weight:500;overflow:hidden}.file-meta{color:var(--text-secondary);font-size:11px}.item-actions{align-items:center;gap:4px;display:flex}.icon-btn{color:var(--text-secondary);cursor:pointer;background:0 0;border:1px solid #0000;border-radius:4px;justify-content:center;align-items:center;width:28px;height:28px;transition:all .2s;display:flex}.icon-btn:hover:not(:disabled){background-color:var(--hover-bg);color:var(--text-primary);border-color:var(--border-color)}.icon-btn:disabled{opacity:.3;cursor:not-allowed}.icon-btn-danger:hover:not(:disabled){color:var(--danger-color);background-color:#dc26261a;border-color:#dc262633}@media (width<=860px){.app{height:auto;min-height:100vh;overflow:visible}.app-header{z-index:30;flex-direction:column;align-items:stretch;position:sticky;top:0}.brand-row,.header-tabs{justify-content:center;margin-left:0}.main-layout{flex-direction:column;overflow:visible}.sidebar{border-right:none;border-bottom:1px solid var(--border-color);width:100%;max-height:none}.workspace{min-height:70vh}.toolbar{flex-direction:column;align-items:stretch;gap:10px}.viewport{justify-content:flex-start;padding:16px}.merge-viewport{padding:24px 16px}}