selection css

::selection {
  background-color: cyan;
}

/*** Works on common browsers ***/
::selection {
    background-color: #352e7e;
    color: #fff;
}

/*** Mozilla based browsers ***/
::-moz-selection {
    background-color: #352e7e;
    color: #fff;
}

/***For Other Browsers ***/
::-o-selection {
    background-color: #352e7e;
    color: #fff;
}

::-ms-selection {
    background-color: #352e7e;
    color: #fff;
}

/*** For Webkit ***/
::-webkit-selection {
    background-color: #352e7e;
    color: #fff;
}

/* Make selected text gold on a red background */
::selection {
  color: gold;
  background-color: red;
}

/* Make selected text in a paragraph white on a blue background */
p::selection {
  color: white;
  background-color: blue;
}

<select>
    <option value="tesla">Tesla</option>
    <option value="volvo">Volvo</option>
    <option value="mercedes">Mercedes</option>
</select">