.export-quiz-pdf-button{ display:none;
}

.watermark {
  -webkit-text-stroke: 1px black; /* borda preta no texto */
  text-shadow:
    -1px -1px 0 #000,
     1px -1px 0 #000,
    -1px  1px 0 #000,
     1px  1px 0 #000,
     0px  0px 6px rgba(0,0,0,0.8); /* melhora contraste */
}

.watermark img {
  filter:
    drop-shadow(-1px -1px 0 black)
    drop-shadow(1px -1px 0 black)
    drop-shadow(-1px 1px 0 black)
    drop-shadow(1px 1px 0 black);
}