* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial;
}

body {
  background: #f5f7fa;
  color: #1f2937;
  height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header */
.topbar {
  background: #0f172a;
  color: #ffffff;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand h1 {
  font-size: 20px;
  font-weight: 600;
}

.brand p {
  font-size: 13px;
  opacity: 0.8;
}

.download-btn {
  background: #2563eb;
  color: #fff;
  padding: 10px 16px;
  border-radius: 6px;
  text-decoration: none;
  font-size: 14px;
  transition: background 0.2s ease;
}

.download-btn:hover {
  background: #1d4ed8;
}

/* PDF Viewer */
.viewer-wrapper {
  flex: 1;
  padding: 12px;
}

.viewer-wrapper iframe {
  width: 100%;
  height: 100%;
  border-radius: 8px;
  background: #fff;
}

/* Footer */
.footer {
  text-align: center;
  padding: 10px;
  font-size: 13px;
  background: #e5e7eb;
}