JSFiddle - React, Tailwind, and code Playground

HTML

<form id="myform" name="org">
    <div>
        <label for="fprovincia" class="form_label float_left enter texto_blanco">Provincia:</label>
        <select class="form_option_1" name="provincias" id="fprovincia">
            <option value="">--</option>
            <option value="1">provincias1</option>
            <option value="1">provincias2</option>
            <option value="1">provincias3</option>
            <option value="1">provincias4</option>
            <option value="1">provincias5</option>
            <option value="1">provincias6</option>
            
        </select>
    </div>
    <div>
        <label for="ms" class="form_label">Localidad:</label>
        <select class="form_option_1" id="ms" name="control_7[]" multiple="multiple" size="0">
            <option value="">-1</option>
            <option value="">-2</option>
            <option value="">-3</option>
            <option value="">-4</option>
            <option value="">-5</option>
            <option value="">-6</option>
            <option value="">-7</option>
            <option value="">-8</option>            
        </select>
    </div>
    <button id="b1" class="boton_5" type="submit" name="b1" disabled="disabled">Search</button>
</form>

CSS

/**
 * @author zhixin wen <[email protected]>
 */

.ms-parent {
    display: inline-block;
    position: relative;
    vertical-align: middle;
}

.ms-choice {
    display: block;
    height: 26px;
    padding: 0;
    overflow: hidden;
    cursor: pointer;
    border: 1px solid #aaa;
    text-align: left;
    white-space: nowrap;
    line-height: 26px;
    color: #444;
    text-decoration: none;
    -webkit-border-radius: 4px;
    -moz-border-radius: 4px;
    border-radius: 4px;
    background-color: #fff;
}

.ms-choice.disabled {
    background-color: #f4f4f4;
    background-image: none;
    border: 1px solid #ddd;
    cursor: default;
}

.ms-choice > span {
    position: absolute;
    top: 0;
    left: 0;
    right: 20px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    display: block;
    padding-left: 8px;
}

.ms-choice > span.placeholder {
    color: #999;
}

.ms-choice > div {
    position: absolute;
    top: 0;
    right: 0;
    width: 20px;
    height: 25px;
    background: url('multiple-select.png') right top no-repeat;
}

.ms-choice > div.open {
    background: url('multiple-select.png') left top no-repeat;
}

.ms-drop {
    overflow: hidden;
    display: none;
    margin-top: -1px;
    padding: 0;
    position: absolute;
    z-index: 1000;
    background: #fff;
    color: #000;
    border: 1px solid #aaa;
    -webkit-border-radius: 4px;
    -moz-border-radius: 4px;
    border-radius: 4px;
}

.ms-drop.bottom {
    top: 100%;
    -webkit-box-shadow: 0 4px 5px rgba(0, 0, 0, .15);
    -moz-box-shadow: 0 4px 5px rgba(0, 0, 0, .15);
    box-shadow: 0 4px 5px rgba(0, 0, 0, .15);
}

.ms-drop.top {
    bottom: 100%;
    -webkit-box-shadow: 0 -4px 5px rgba(0, 0, 0, .15);
    -moz-box-shadow: 0 -4px 5px rgba(0, 0, 0, .15);
    box-shadow: 0 -4px 5px rgba(0, 0, 0, .15);
}

.ms-search {
    display: inline-block;
    margin: 0;
    min-height: 26px;
    padding: 4px;
    position: relative;
    white-space: nowrap;
    width:...