message: fix button colors
diff: @@ -211,11 +211,11 @@ mdl-simple-tooltip div {
  margin-top: 6px !important;
  }
  -.mdl-button {
  +.mdl-button mdl-icon {
  color: black !important;
  }
  -.mdl-button[disabled][disabled], .mdl-button.mdl-button--disabled.mdl-button--disabled {
  +.mdl-button[disabled][disabled] mdl-icon, .mdl-button.mdl-button--disabled.mdl-button--disabled mdl-icon {
  color: rgba(0,0,0,.26) !important;
  cursor: default;
  background-color: transparent;
  