Changing the Matching dropdown graded quiz/survey colors

I don't see a way to change the font color only for the selected answer. You can add another CSS rule (e.g., .drop-list text), but it seems to affect the font color of all drop-list items.

const style = document.createElement('style');
style.innerHTML = `
  .drop-list-item-selected {
    fill: #87CEEB !important; 
  }
  .drop-list text {
    fill: #2a2b2c !important;
}
`;
document.head.appendChild(style);

More CSS properties you can play with:

const style = document.createElement('style');
style.innerHTML = `
  .drop-list-item-selected {
    fill: #87CEEB !important; 
}
  .drop-list text {
    fill: #2a2b2c !important;
}
  .drop-list-drop-down text {
    fill: #fff !important;
}
  .drop-list-item-out {
    fill: #222 !important;
}
  .drop-list-item-over {
    fill: #aaa !important;
}
   #drop-list-gradient stop:first-child {
    stop-color: #222 !important;
}
   #drop-list-gradient stop:last-child {
    stop-color: #aaa !important;
}
  .drop-list-top > rect {
    fill: aliceblue !important;
}
`;
document.head.appendChild(style);