addons.css

/* show-hint */
.CodeMirror-hints {
  position: absolute;
  z-index: 10;
  overflow: hidden;
  list-style: none;

  margin: 0;
  padding: 2px;

  -webkit-box-shadow: 2px 3px 5px rgba(0,0,0,.2);
  -moz-box-shadow: 2px 3px 5px rgba(0,0,0,.2);
  box-shadow: 2px 3px 5px rgba(0,0,0,.2);
  border-radius: 3px;
  border: 1px solid silver;

  background: white;
  font-size: 90%;
  font-family: monospace;

  max-height: 20em;
  overflow-y: auto;
}

.CodeMirror-hint {
  margin: 0;
  padding: 0 4px;
  border-radius: 2px;
  white-space: pre;
  color: black;
  cursor: pointer;
}

li.CodeMirror-hint-active {
  background: #08f;
  color: white;
}

/* dialog */

.CodeMirror-dialog {
  position: absolute;
  left: 0; right: 0;
  background: inherit;
  z-index: 15;
  padding: .1em .8em;
  overflow: hidden;
  color: inherit;
}

.CodeMirror-dialog-top {
  border-bottom: 1px solid #eee;
  top: 0;
}

.CodeMirror-dialog-bottom {
  border-top: 1px solid #eee;
  bottom: 0;
}

.CodeMirror-dialog input {
  border: none;
  outline: none;
  background: transparent;
  width: 20em;
  color: inherit;
  font-family: monospace;
}

.CodeMirror-dialog button {
  font-size: 70%;
}
/* matchesonscrollbar */
.CodeMirror-search-match {
  background: gold;
  border-top: 1px solid orange;
  border-bottom: 1px solid orange;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
  opacity: .5;
}