list item highlighted but not the entire row - html

Question

My current fiddle is working fine apart from one thing. When I hover over the button I see the list displayed. Then when I hover over a list item the background changes colour which is all fine. However when the list item changes colour there is almost a box to the left of the item which is not highlighted and can't seem to get rid of it?
.dropbtn {
background-color: #9FACEC;
color: white;
padding: 16px;
font-size: 16px;
border: none;
}
.dropdown {
position: relative;
display: inline-block;
}
.dropdown-content {
display: none;
position: absolute;
background-color: #f1f1f1;
min-width: 160px;
box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
z-index: 1;
}
.dropdown-content li {
color: black;
padding: 12px 16px;
text-decoration: none;
display: block;
}
.dropdown-content li:hover {background-color: #ddd;}
.dropdown:hover .dropdown-content {display: block;}
.dropdown:hover .dropbtn {background-color: #4C66E9;}

Answer 1

If i understand you. i believe you are looking to remove ui margin. you can do that using
ul{
padding: 0;
margin: 0;
}

Answer 2

By default most of HTML tags has some default styling, same is here in ul tag and that's the reason that when you hover li tags the left-side is not highlighted.
Default ul styling,
ul{
display: block;
list-style-type: disc;
margin-top: 1em;
margin-bottom: 1 em;
margin-left: 0;
margin-right: 0;
padding-left: 40px;
}
$(document).ready(function() {
var $region = $('#regionList');
$region.append('<li id="Europe">Europe</li>');
$region.append('<li id="Japan">Japan</li>');
$region.append('<li id="North America">North America</a></li>');
$("#regionList li").click(function() {
alert('Clicked list. ' + this.id);
});
})
/* Dropdown Button */
.dropbtn {
background-color: #9FACEC;
color: white;
padding: 16px;
font-size: 16px;
border: none;
}
/* The container <div> - needed to position the dropdown content */
.dropdown {
position: relative;
display: inline-block;
}
ul {
padding: 0px;
margin: 0px;
}
/* Dropdown Content (Hidden by Default) */
.dropdown-content {
display: none;
position: absolute;
background-color: #f1f1f1;
min-width: 160px;
box-shadow: 0px 8px 16px 0px rgba(0, 0, 0, 0.2);
z-index: 1;
}
/* Links inside the dropdown */
.dropdown-content li {
color: black;
padding: 12px 16px;
text-decoration: none;
display: block;
}
/* Change color of dropdown links on hover */
.dropdown-content li:hover {
background-color: #ddd;
}
/* Show the dropdown menu on hover */
.dropdown:hover .dropdown-content {
display: block;
}
/* Change the background color of the dropdown button when the dropdown content is shown */
.dropdown:hover .dropbtn {
background-color: #4C66E9;
}
.selected {
background: #FF00FF;
}
/*Add this*/
ul{
padding-left:0px;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="dropdown">
<button class="dropbtn">Regions</button>
<div class="dropdown-content">
<ul id="regionList"></ul>
</div>
</div>

Answer 3

I believe below approach solves your problem. It was caused by ul element having default padding. I also added box-sizing: border-box to list elements, so padding won't make li elements stick out of ul.
I added explanation below snippet.
Solution key part
.dropdown-content #regionList {
padding: 0;
}
.dropdown-content li {
color: black;
padding: 12px 16px;
box-sizing: border-box;
text-decoration: none;
display: block;
}
Snippet
$(document).ready(function() {
var $region = $('#regionList');
$region.append('<li id="Europe">Europe</li>');
$region.append('<li id="Japan">Japan</li>');
$region.append('<li id="North America">North America</a></li>');
$("#regionList li").click(function() {
alert('Clicked list. ' + this.id);
});
})
/* Dropdown Button */
.dropbtn {
background-color: #9FACEC;
color: white;
padding: 16px;
font-size: 16px;
border: none;
}
/* The container <div> - needed to position the dropdown content */
.dropdown {
position: relative;
display: inline-block;
}
/* Dropdown Content (Hidden by Default) */
.dropdown-content {
display: none;
position: absolute;
background-color: #f1f1f1;
min-width: 160px;
box-shadow: 0px 8px 16px 0px rgba(0, 0, 0, 0.2);
z-index: 1;
}
/* Links inside the dropdown */
.dropdown-content #regionList {
padding: 0;
}
.dropdown-content li {
color: black;
padding: 12px 16px;
box-sizing: border-box;
text-decoration: none;
display: block;
}
/* Change color of dropdown links on hover */
.dropdown-content li:hover {
background-color: #ddd;
}
/* Show the dropdown menu on hover */
.dropdown:hover .dropdown-content {
display: block;
}
/* Change the background color of the dropdown button when the dropdown content is shown */
.dropdown:hover .dropbtn {
background-color: #4C66E9;
}
.selected {
background: #FF00FF;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="dropdown">
<button class="dropbtn">Regions</button>
<div class="dropdown-content">
<ul id="regionList"></ul>
</div>
</div>
Explanation
Problem is caused by browser's default CSS rules, which are for Chrome:
ul, menu, dir {
display: block;
list-style-type: disc;
-webkit-margin-before: 1em;
-webkit-margin-after: 1em;
-webkit-margin-start: 0px;
-webkit-margin-end: 0px;
-webkit-padding-start: 40px;
}
You can see more here.

Answer 4

The other answers are correct. I just wanted to explain what's going on.
Your user agent stylesheet contains -webkit-padding-start: 40px; for ul elements.
Represented here in green.
As other answers said, override the padding style for ul elements set by your user agent stylesheet.

Answer 5

Just add padding 0 to your regionList
#regionList{
padding : 0;
}