:root {
  --bg: #f4f5f7;
  --card-bg: #ffffff;
  --border: #e2e4e9;
  --text: #1c1f26;
  --text-muted: #6b7280;
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --success: #16a34a;
  --success-bg: #ecfdf3;
  --danger: #dc2626;
  --danger-bg: #fef2f2;
  --radius: 12px;
  --shadow: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
}

.app {
  max-width: 640px;
  margin: 0 auto;
  padding: 32px 20px 60px;
}

.app-header {
  text-align: center;
  margin-bottom: 28px;
}

.app-header h1 {
  font-size: 28px;
  font-weight: 700;
  margin: 0 0 8px;
}

.subtitle {
  color: var(--text-muted);
  margin: 0 0 16px;
  font-size: 15px;
}

.privacy-banner {
  display: inline-block;
  background: var(--success-bg);
  color: var(--success);
  border: 1px solid #bbf7d0;
  padding: 8px 16px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 500;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
  margin-bottom: 20px;
}

.hidden { display: none !important; }

/* Dropzone */
.dropzone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 48px 20px;
  text-align: center;
  transition: border-color 0.15s, background 0.15s;
}

.dropzone.drag-over {
  border-color: var(--primary);
  background: #eff6ff;
}

.dropzone-icon { font-size: 40px; margin-bottom: 8px; }
.dropzone-text { font-size: 17px; font-weight: 600; margin: 0 0 4px; }
.dropzone-or { color: var(--text-muted); font-size: 13px; margin: 8px 0; }

/* Buttons */
.btn {
  border: none;
  border-radius: 8px;
  padding: 11px 22px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s, transform 0.05s;
}
.btn:active { transform: scale(0.98); }

.btn-primary {
  background: var(--primary);
  color: white;
}
.btn-primary:hover { background: var(--primary-hover); }
.btn-primary:disabled {
  background: #93c5fd;
  cursor: not-allowed;
}

.btn-big {
  width: 100%;
  padding: 14px 22px;
  font-size: 15px;
  margin-top: 8px;
}

.btn-text {
  background: none;
  border: none;
  color: var(--primary);
  font-size: 13px;
  cursor: pointer;
  padding: 8px 0;
  display: block;
  margin: 4px auto 0;
}
.btn-text:hover { text-decoration: underline; }

/* File info */
.file-info {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px 14px;
  padding-bottom: 18px;
  margin-bottom: 18px;
  border-bottom: 1px solid var(--border);
}
.file-info-name {
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 8px;
  width: 100%;
}
.file-icon { font-size: 18px; }
.file-info-size {
  color: var(--text-muted);
  font-size: 13px;
}
.page-count { margin-left: 6px; }
#btnRemove { margin: 0 0 0 auto; }

.section-label {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted);
  margin: 0 0 10px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

/* Quality selector */
.quality-options {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  margin-bottom: 20px;
}

.quality-btn {
  border: 1.5px solid var(--border);
  background: white;
  border-radius: 10px;
  padding: 12px 14px;
  text-align: left;
  cursor: pointer;
  display: flex;
  flex-direction: column;
  gap: 3px;
  transition: border-color 0.15s, background 0.15s;
}

.quality-btn:hover { border-color: #93c5fd; }

.quality-btn.active {
  border-color: var(--primary);
  background: #eff6ff;
}

.q-title { font-weight: 600; font-size: 14px; }
.q-desc { font-size: 12px; color: var(--text-muted); }

/* Advanced settings */
.advanced {
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 4px 16px;
  margin-bottom: 18px;
}

.advanced summary {
  cursor: pointer;
  padding: 12px 0;
  font-weight: 600;
  font-size: 14px;
  color: var(--text);
}

.advanced-grid {
  display: flex;
  flex-direction: column;
  gap: 16px;
  padding: 4px 0 16px;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 13px;
  color: var(--text-muted);
}

.field input[type="range"] { accent-color: var(--primary); }

.checkbox-field {
  flex-direction: row;
  align-items: center;
  gap: 8px;
}
.checkbox-field input { width: 16px; height: 16px; }
.checkbox-field span { color: var(--text); font-size: 14px; }

/* Progress */
.progress-title { font-weight: 600; margin: 0 0 14px; }

.progress-bar-track {
  width: 100%;
  height: 10px;
  background: var(--border);
  border-radius: 999px;
  overflow: hidden;
  margin-bottom: 10px;
}

.progress-bar-fill {
  height: 100%;
  width: 0%;
  background: var(--primary);
  border-radius: 999px;
  transition: width 0.2s ease;
}

.progress-text {
  font-size: 13px;
  color: var(--text-muted);
  margin: 0;
  text-align: center;
}

/* Result */
.result-title {
  font-weight: 700;
  font-size: 17px;
  color: var(--success);
  margin: 0 0 20px;
  text-align: center;
}

.result-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 20px;
}

.result-box {
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 14px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.result-box.highlight {
  border-color: var(--success);
  background: var(--success-bg);
}

.result-label {
  font-size: 12px;
  color: var(--text-muted);
}

.result-value {
  font-size: 18px;
  font-weight: 700;
}

.result-box.highlight .result-value { color: var(--success); }

/* Error */
.error-box {
  background: var(--danger-bg);
  border: 1px solid #fecaca;
  color: var(--danger);
  padding: 14px 16px;
  border-radius: 10px;
  font-size: 14px;
  margin-top: 16px;
}

.app-footer {
  text-align: center;
  color: var(--text-muted);
  font-size: 12px;
  margin-top: 30px;
}

@media (max-width: 480px) {
  .quality-options { grid-template-columns: 1fr; }
  .result-grid { grid-template-columns: 1fr; }
}