消除文本框之间的空格

I have something like this :

$form->addElement(new Element\Textbox("M_89 :",$M_89,array("onchange"=> "this.form.submit()","value"=> $M_89)));
$form->addElement(new Element\Textbox("M_90 :",$M_90,array("onchange"=> "this.form.submit()","value"=> $M_90)));

And it has space between those buttons. I want the buttons side by side. How can I do that? Is there a way without HTML?

HTML code?
<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="utf-8">
        <title></title>
        <meta name="viewport" content="width=device-width, initial-scale=1.0">

<style type="text/css">
    body {
        padding-top: 60px;
        padding-bottom: 40px;
    }
    .sidebar-nav {
        padding: 9px 0;
    }
</style>