fix dark theme

javascript/app.js

@@ -174,6 +174,8 @@ class MidiVisualizer extends HTMLElement{
  allTrackBtn.textContent = "All";
  allTrackBtn.style.width = "50%";
  allTrackBtn.style.height = "100%";
+ allTrackBtn.style.backgroundColor = "rgba(200, 200, 200, 0.3)";
+ allTrackBtn.style.color = 'inherit';
  allTrackBtn.style.border = "none";
  allTrackBtn.style.cursor = 'pointer';
  let self = this;
@@ -186,6 +188,8 @@ class MidiVisualizer extends HTMLElement{
  noneTrackBtn.textContent = "None";
  noneTrackBtn.style.width = "50%";
  noneTrackBtn.style.height = "100%";
+ noneTrackBtn.style.backgroundColor = "rgba(200, 200, 200, 0.3)";
+ noneTrackBtn.style.color = 'inherit';
  noneTrackBtn.style.border = "none";
  noneTrackBtn.style.cursor = 'pointer';
  noneTrackBtn.onclick = function (){
@@ -281,7 +285,7 @@ class MidiVisualizer extends HTMLElement{
  }
  track.setEmpty = function (empty){
  if (empty!==track.empty){
- content.style.color = empty?"grey":"black";
+ content.style.color = empty?"grey":"inherit";
  }
  }