Aligning an html form so all labels link up - php

Question

I'm trying to align my form up so that all labels start at the same and then also the textboxes start at the same spot. When using float:left all the labels are starting at the same point but the textboxes just follow on so textboxes are all messed up. Is there a way I can set so that all textboxes so start at a specific point on the page. I am using CSS but not to sure which attributes I need to be using. The form I've got is;
<form method="POST" action="editloaninfo.php">
<div id="editp"Username:
<input type="text" name="username" autocomplete="off" size="18" value="<?php echo $username; ?>"></div>
<br>
<div id="editp"Product:
<select name="product" style="width: 150px">
<option value="<?php echo $product;?>">
<option value="Laptop">Laptop</option>
<option value="Keyboard">Keyboard</option>
</select></div>
The div for edit is;
#editp {
font-family: Tahoma, Geneva, sans-serif;
font-style: italic;
font-size: 80%;
margin-right: 100px;
float: left;
}

Answer 1

If I understand correctly you just need to set a width on the label, to that of the longest label so that elements next to them align with each other.
See this fiddle - https://jsfiddle.net/yya26ark/
HTML:
<label>Example Label:</label><input type="text">
<label>Example:</label><input type="text">
<label>Label Ex:</label><input type="text">
<label>Something Else Here:</label><input type="text">
CSS:
label { display:inline-block; width:200px; }
input { width:120px; }

Answer 2

Close your opening div tags. You're missing a >.
Don't use inline styles
Use form labels!
Then just use inline block and widths to control positioning of labels to inputs:
form {
width: 100%;
}
label {
width: 30%;
display: inline-block;
}
input,
select {
width: 60%;
display: inline-block;
margin: 0;
}
<form method="POST" action="editloaninfo.php">
<div id="editp">
<label for="username">Username:</label>
<input type="text" name="username" autocomplete="off" value="<?php echo $username; ?>">
</div>
<br>
<div id="editp">
<label for="product">Product:</label>
<select name="product">
<option value="<?php echo $product;?>">
<option value="Laptop">Laptop</option>
<option value="Keyboard">Keyboard</option>
</select>
</div>
</form>