:root {
  --bg: #f6f7f9;
  --card-bg: #ffffff;
  --text: #1f2937;
  --muted: #6b7280;

  --primary-bg: #22c55e;
  --primary-hover: #16a34a;
  --primary-text: #ffffff;

  --accent-bg: #f59e0b;
  --accent-hover: #d97706;
  --accent-text: #1f2937;

  --border: #e5e7eb;
  --shadow: 0 8px 24px rgba(0,0,0,0.08);

  --drop-bg: #e0f2fe;
  --drop-border: #93c5fd;
  --drop-text: #0ea5e9;

  --page-bg: #ffffff;
  --page-border: #e5e7eb;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b1020;
    --card-bg: #121926;
    --text: #e5e7eb;
    --muted: #94a3b8;

    --primary-bg: #22c55e;
    --primary-hover: #16a34a;
    --primary-text: #0b1020;

    --accent-bg: #f59e0b;
    --accent-hover: #d97706;
    --accent-text: #0b1020;

    --border: #273449;
    --shadow: 0 10px 28px rgba(0,0,0,0.35);

    --drop-bg: #082f49;
    --drop-border: #0ea5e9;
    --drop-text: #7dd3fc;

    --page-bg: #0b1020;
    --page-border: #273449;
  }
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji","Segoe UI Emoji";
  background: var(--bg);
  color: var(--text);
}

#app {
  max-width: 1100px;
  margin: 0 auto;
  padding: 24px;
}

.page-title {
  margin: 0 0 16px;
  font-size: 2rem;
  letter-spacing: 0.2px;
  text-align: center;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  border-radius: 16px;
  padding: 28px;
  text-align: center;
}

.hint {
  margin-top: 10px;
  color: var(--muted);
  font-size: 0.95rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 48px;
  min-width: 220px;
  padding: 0 18px;
  border-radius: 999px;
  border: none;
  font-weight: 600;
  cursor: pointer;
  transition: all 150ms ease;
  box-shadow: var(--shadow);
}

.btn[disabled] {
  opacity: 0.6;
  cursor: not-allowed;
}

.btn-primary {
  background: var(--primary-bg);
  color: var(--primary-text);
}
.btn-primary:hover { background: var(--primary-hover); }

.btn-accent {
  background: var(--accent-bg);
  color: var(--accent-text);
}
.btn-accent:hover { background: var(--accent-hover); }

.drop-zone {
  margin: 18px auto 0;
  width: min(720px, 95%);
  min-height: 140px;
  border: 2px dashed var(--drop-border);
  background: var(--drop-bg);
  border-radius: 16px;
  display: grid;
  place-items: center;
  color: var(--drop-text);
  user-select: none;
}
.drop-zone.dragover {
  outline: 4px solid var(--drop-border);
  filter: brightness(1.05);
}
.drop-zone__label {
  font-weight: 600;
  font-size: 1.1rem;
}

.status {
  margin-top: 16px;
  text-align: center;
  color: var(--muted);
}

/* Utility */
.hidden { display: none !important; }

/* Viewer */
.viewer.hidden { display: none; }
.viewer {
  margin-top: 24px;
}

.pages {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
}

.page {
  position: relative;
  background: var(--page-bg);
  border: 1px solid var(--page-border);
  border-radius: 12px;
  box-shadow: var(--shadow);
  overflow: hidden;
  padding: 0;
}

.page canvas {
  display: block;
  width: 100%;
  height: auto;
}

/* text layer sovrapposto al canvas per avere testo selezionabile */
.textLayer {
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;   /* verrà ridimensionato in js */
  height: 100%;  /* idem */
  color: transparent;      /* testo invisibile ma selezionabile */
  pointer-events: auto;    /* CONSENTE la selezione */
  z-index: 5;              /* sopra il canvas */
  -webkit-user-select: text;
  user-select: text;
}

.textLayer span {
  position: absolute;
  white-space: pre;
  transform-origin: 0 0;
  line-height: 1;
  -webkit-user-select: text;
  user-select: text;
}

/* evidenziazione durante la selezione (opzionale) */
.textLayer ::selection {
  background: rgba(0, 140, 255, 0.25);
}

/* Azioni in fondo */
.actions {
  margin: 20px 0 10px;
  display: flex;
  justify-content: center;
  gap: 14px;
  flex-wrap: wrap;
}

/* Embedded PDF viewer wrapper (per <embed> o <object>) */
.embedWrapper {
  width: 100%;
  height: calc(100vh - 220px); /* spazio visibile grande per il PDF */
  border: 1px solid var(--border);
  border-radius: 12px;
  box-shadow: var(--shadow);
  overflow: hidden;
  background: var(--card-bg);
}
.embedWrapper embed,
.embedWrapper object {
  width: 100%;
  height: 100%;
  border: 0;
  background: var(--card-bg);
}

/* Responsivo */
@media (max-width: 640px) {
  .btn { min-width: 180px; height: 44px; }
  .embedWrapper { height: calc(100vh - 180px); }
}