:root {
  --primary: #3A6FF8;
  --accent: #00C2A8;
  --dark: #0F172A;
  --light: #F8FAFC;
  --text: #1F2937;
  --border: #E5E7EB;
  --warn: #F59E0B;
  --danger: #EF4444;
}

* { box-sizing: border-box; }
html, body { margin:0; padding:0; font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto; color: var(--text); background: var(--light); }

.topbar {
  display:flex; align-items:center; justify-content:space-between;
  padding:12px 20px; border-bottom:1px solid var(--border); background:#fff;
}
.logo { font-weight:700; color: var(--primary); }
.actions { display:flex; gap:10px; }

.btn { padding:10px 14px; border-radius:10px; border:1px solid var(--border); background:#fff; cursor:pointer; }
.btn.primary { background: var(--primary); color:#fff; border:none; }
.btn.secondary { background: var(--accent); color:#fff; border:none; }
.btn.ghost { background: transparent; }
.btn.wide { width:100%; }

.container { display:grid; grid-template-columns: 2fr 1fr; gap:20px; padding:20px; }
@media (max-width: 900px) {
  .container { grid-template-columns: 1fr; }
  .sidebar { order:2; }
}

.uploader { background:#fff; border:1px solid var(--border); border-radius:12px; padding:16px; }
.dropzone {
  border:2px dashed var(--border); border-radius:12px; padding:30px; text-align:center;
  transition: border-color .2s, background .2s;
}
.dropzone.dragover { border-color: var(--primary); background:#F0F4FF; }
.drop-content { display:flex; flex-direction:column; align-items:center; gap:10px; }
.drop-icon { font-size:36px; }

.file-list { list-style:none; margin:16px 0 0; padding:0; display:grid; gap:12px; }
.file-card {
  display:flex; align-items:center; gap:12px; padding:10px; border:1px solid var(--border); border-radius:10px; background:#fff;
}
.file-thumb { width:48px; height:48px; background:#F3F4F6; border-radius:8px; display:flex; align-items:center; justify-content:center; font-size:20px; }
.file-info { flex:1; }
.file-actions { display:flex; gap:8px; }

.sidebar {
  background:#fff; border:1px solid var(--border); border-radius:12px; padding:16px; position:sticky; top:20px; height: max-content;
}
.tabs { display:flex; gap:6px; flex-wrap:wrap; margin-bottom:10px; }
.tab { padding:8px 10px; border:1px solid var(--border); border-radius:8px; cursor:pointer; }
.tab.active { background:#EEF2FF; border-color:#C7D2FE; color:#1E3A8A; }

.panel.hidden { display:none; }
.panel label { display:block; margin:10px 0; }
.panel .row { display:flex; gap:10px; }

.modal { position:fixed; inset:0; background: rgba(15,23,42,0.6); display:flex; align-items:center; justify-content:center; }
.modal.hidden { display:none; }
.modal-content { background:#fff; border-radius:12px; width:min(1000px, 94vw); height:min(80vh, 700px); display:flex; flex-direction:column; }
.modal-toolbar { display:flex; gap:8px; padding:10px; border-bottom:1px solid var(--border); }
.preview-pages { flex:1; overflow:auto; padding:12px; display:grid; grid-template-columns: 1fr 1fr; gap:12px; }
@media (max-width:900px){ .preview-pages { grid-template-columns: 1fr; } }
.preview-page { border:1px solid var(--border); border-radius:8px; background:#fff; position:relative; }
.preview-page .page-tools { position:absolute; top:6px; right:6px; display:flex; gap:6px; }

.overlay { position:fixed; inset:0; background: rgba(15,23,42,0.5); display:flex; align-items:center; justify-content:center; }
.overlay.hidden { display:none; }
.progress { background:#fff; padding:20px; border-radius:12px; display:flex; align-items:center; gap:12px; }
.spinner {
  width:24px; height:24px; border:3px solid #ddd; border-top-color: var(--primary);
  border-radius:50%; animation:spin 1s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.dark body { background: var(--dark); color:#E5E7EB; }
.dark .topbar, .dark .uploader, .dark .sidebar, .dark .modal-content, .dark .progress { background:#0B1220; border-color:#1F2937; }
.dark .dropzone { border-color:#1F2937; }