Customizing Select Dropdowns in CSS

While you can’t style select dropdowns fully with CSS alone, you can improve their appearance with some basic styling.

Source Code

select {
    background-color: white;
    border: thin solid blue;
    border-radius: 4px;
    display: inline-block;
    font: inherit;
    line-height: 1.5em;
    padding: 0.5em 3.5em 0.5em 1em;
    margin: 0;
    box-sizing: border-box;
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    background-image: linear-gradient(45deg, transparent 50%, gray 50%), linear-gradient(135deg, gray 50%, transparent 50%);
    background-position: calc(100% - 20px) calc(1em + 2px), calc(100% - 15px) calc(1em + 2px), 100% 0;
    background-size: 5px 5px, 5px 5px;
    background-repeat: no-repeat;
}