How to change the dropdown styling?

How can I style this dropdown menu to look like the attached dropdown that is in the green rectangle?

this is the form i need styled: https://form.jotform.com/80433929758166

The screenshot you have shared displays the dropdown question in full width, increased height along with the font color. The form background seems to be different and that is the reason why the dropdown appears correctly without border.

Please confirm if you just want to change the width of the dropdown along with the font change or you want some other changes as well. 

We will wait for your response.

yes change the width to be fullwidth and font change as well.

Kindly add these css codes in your form.

select#input_3{
  width:600px !important;
}
#cid_3{
 
width: 500px!important;
}

Guide on How-to-Inject-Custom-CSS-Codes

Please let us know if you have further questions.

how do i remove the border/drop shadow and the white background?

Kindly copy and paste these css codes,to your form and overwrite them.

[data-type="control_dropdown"] .form-input, [data-type="control_dropdown"] .form-input-wide {
    width : 150px !important;
}

select#input_3 {
    border : none !important;
    padding : 5px 15px !important;
    color : #000000 !important;
    width : 240px !important;
    height : 30px;
    font-size : 15px;
}

li#id_3 > div.form-input-wide:before {
 
    right : -83px;
    height : 20px;
    width : 30px;
    top : 5px;
    border : none !important;
}

li#id_3 > div.form-input-wide:after {
   
    right : -75px;
  
}

select#input_3 option:nth-child(even) {
    background : #f2f2f2;
    height : 30px !important;
}

select#input_3 option:nth-child(odd) {
    background : #dedfe1;
}

select#input_3 option:first-child {
    display : none !important;
}

supernova .form-all, .form-all {
    background-color: transparent !important;
    border: none !important;
}


.form-all {
 
 background-color:transparent !important
 background:none !important;
 
}
select#input_3{
  width:600px !important;
}
#cid_3{
 
width: 500px!important;
}
li[data-type="control_dropdown"] > div.form-input:after, li[data-type="control_dropdown"] > div.form-input-wide:after, li[data-type="control_time"] div .form-sub-label-container:after{
  border-color: #151313 transparent transparent transparent !important;
}

To change your backgound you can use this css code.

select#input_3{

background:your preferred background color;

}

Please let us know if we can be of further assistance.

http://m2p.417.myftpupload.com/

On my site- you see that there is a large white background around the dropdown form.

Also, the make a selection text larger and light shade of grey.

To increase your font-size,in your select#input_3 you can add font:size 22px;

select#input_3{

  font-size: 22px;

}

To change the background of the item to light gray

select#input_3 option:nth-child(even) {
    background : #dedfe1!important;
   
}

The white background in your website is your form Page Color, you can change that in your Form Designer>Page color

Let us know how it goes.