return-youtube-dislike/Extensions/firefox/content-style.css

#return-youtube-dislike-bar-container {
  background: #c6c6c6;
}

#return-youtube-dislike-bar {
  background: #5094c8;
}

[dark] #return-youtube-dislike-bar-container {
}

[dark] #return-youtube-dislike-bar {
  background: #3ea6ff;
}

.ryd-tooltip {
  position: relative;
  display: inline-block;
  border-bottom: 1px dotted black; /* If you want dots under the hoverable text */
  cursor: pointer;
  height: 10px;
  margin-bottom: -5px;
}

/* Tooltip text */
.ryd-tooltip .ryd-tooltiptext {
  visibility: hidden;
  width: 120px;
  background-color: #000000c4;
  color: #fff;
  text-align: center;
  padding: 5px 0;
  border-radius: 6px;

  /* Position the tooltip text - see examples below! */
  position: absolute;
  z-index: 1;
  bottom: 15px;
  left: 10px;
  font-size: 12px;
}

/* Show the tooltip text when you mouse over the tooltip container */
.ryd-tooltip:hover .ryd-tooltiptext {
  visibility: visible;
}