Semantic search multiple Dropdown design (Pillbox) Is not created

I am trying to add searchable multiple value dropdown in my webpage but instead of getting (Pillbox) design it shows default design to me.

This is the result that I got by placing the same code from Semantic Website

My Code in PHP file is as:

<select class="ui fluid search dropdown" multiple="">
                                    <option value="">State</option>
                                    <option value="AL">Alabama</option>
                                    <option value="AK">Alaska</option>
                                    <option value="AZ">Arizona</option>
                                    <option value="AR">Arkansas</option>
                                    <option value="CA">California</option>
                                    <option value="CO">Colorado</option>
                                    <option value="CT">Connecticut</option>
                                    <option value="DE">Delaware</option>
                                    <option value="DC">District Of Columbia</option>
                                    <option value="FL">Florida</option>
                                    <option value="GA">Georgia</option>
                                    <option value="HI">Hawaii</option>
                                    <option value="ID">Idaho</option>
                                    <option value="IL">Illinois</option>
                                    <option value="IN">Indiana</option>
                                    <option value="IA">Iowa</option>
                                    <option value="KS">Kansas</option>
                                    <option value="KY">Kentucky</option>
                                    <option value="LA">Louisiana</option>
                                    <option value="ME">Maine</option>
                                    <option value="MD">Maryland</option>
                                    <option value="MA">Massachusetts</option>
                                    <option value="MI">Michigan</option>
                                    <option value="MN">Minnesota</option>
                                    <option value="MS">Mississippi</option>
                                    <option value="MO">Missouri</option>
                                    <option value="MT">Montana</option>
                                    <option value="NE">Nebraska</option>
                                    <option value="NV">Nevada</option>
                                    <option value="NH">New Hampshire</option>
                                    <option value="NJ">New Jersey</option>
                                    <option value="NM">New Mexico</option>
                                    <option value="NY">New York</option>
                                    <option value="NC">North Carolina</option>
                                    <option value="ND">North Dakota</option>
                                    <option value="OH">Ohio</option>
                                    <option value="OK">Oklahoma</option>
                                    <option value="OR">Oregon</option>
                                    <option value="PA">Pennsylvania</option>
                                    <option value="RI">Rhode Island</option>
                                    <option value="SC">South Carolina</option>
                                    <option value="SD">South Dakota</option>
                                    <option value="TN">Tennessee</option>
                                    <option value="TX">Texas</option>
                                    <option value="UT">Utah</option>
                                    <option value="VT">Vermont</option>
                                    <option value="VA">Virginia</option>
                                    <option value="WA">Washington</option>
                                    <option value="WV">West Virginia</option>
                                    <option value="WI">Wisconsin</option>
                                    <option value="WY">Wyoming</option>
                                </select>

I have included initialization also:

<script type='text/javascript'>//<![CDATA[

$(document).ready(function() {
    $(function () {
        $('.ui.dropdown').dropdown();
    });
});
</script>

I have been searching on internet and following any suggestions from Stackoverflow that i could find. some of those threads are:

1. Stackoverflow
2. Second Link

There were some other links too that I cloased earlier.

Please if you know solution help me out!