:root {
  --bg: #0f172a;
  --panel: #111827;
  --panel-2: #1f2937;
  --text: #e5e7eb;
  --muted: #9ca3af;
  --primary: #2563eb;
  --danger: #dc2626;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: linear-gradient(180deg, #0f172a, #020617);
  color: var(--text);
}

header {
  padding: 1rem 1.5rem;
  border-bottom: 1px solid #334155;
  background: rgba(2, 6, 23, 0.9);
  position: sticky;
  top: 0;
  z-index: 10;
}

header h1 {
  margin: 0;
  font-size: 1.4rem;
}

header p {
  margin: 0.25rem 0 0;
  color: var(--muted);
}

main {
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: 1rem;
  padding: 1rem;
}

.toolbar {
  background: var(--panel);
  border: 1px solid #334155;
  border-radius: 12px;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  height: fit-content;
}

.group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

label,
small,
#pageIndicator {
  color: var(--muted);
}

input[type="text"],
input[type="file"],
button {
  width: 100%;
  border-radius: 8px;
  border: 1px solid #475569;
  background: var(--panel-2);
  color: var(--text);
  padding: 0.5rem 0.6rem;
}

button {
  cursor: pointer;
  transition: transform 0.06s ease, background 0.2s ease;
}

button:hover {
  background: #334155;
}

button:active {
  transform: scale(0.98);
}

.primary {
  background: var(--primary);
  border-color: #1d4ed8;
}

.primary:hover {
  background: #1d4ed8;
}

#deletePageBtn {
  border-color: #7f1d1d;
  background: #450a0a;
}

#deletePageBtn:hover {
  background: #7f1d1d;
}

.viewer-wrapper {
  background: var(--panel);
  border: 1px solid #334155;
  border-radius: 12px;
  padding: 1rem;
  min-height: 75vh;
}

#pdfCanvas {
  width: 100%;
  background: #f9fafb;
  border-radius: 8px;
  cursor: crosshair;
}

#status {
  margin-top: 0.75rem;
  color: var(--muted);
}

.feature-note {
  grid-column: 1 / -1;
  background: #0b1220;
  border: 1px solid #334155;
  border-radius: 12px;
  padding: 1rem;
}

@media (max-width: 980px) {
  main {
    grid-template-columns: 1fr;
  }
}