"background-size: cover" does not cover mobile screen - html

Question

I have a photo background on my site using background-size:cover. It works for the most part but leaves a weird ~30px white space on my Galaxy S3 in portrait mode.
I've attached a screenshot. The 1px teal line is to illustrate the entire screen. Seems like the background stops right after the social media uls.
I tested this by removing the ul and the background attached it self to the bottom of the tagline text.
Also, here's my CSS pertaining mobile portait view:
#media only screen and (max-width: 480px) {
.logo {
position: relative;
background-size:70%;
-webkit-background-size: 70%;
-moz-background-size: 70%;
-o-background-size: 70%;
margin-top: 30px;
}
h1 {
margin-top: -25px;
font-size: 21px;
line-height: 21px;
margin-bottom: 15px;
}
h2 {
font-size: 35px;
line-height: 35px;
}
.footer_mobile {
display: block;
margin-top: 20px;
margin-bottom: 0px;
}
li {
display: block;
font-size: 1.3em;
}
This used to not happen, but I guess I accidentally bugged it while trying to solve another issue.

Answer 1

After hours of trying different things, adding min-height: 100%; to the bottom of html under the { background:... } worked for me.

Answer 2

This works on Android 4.1.2 and iOS 6.1.3 (iPhone 4) and switches for desktop. Written for responsive sites.
Just in case, in your HTML head, something like this:
<meta name="viewport" content="width=device-width, initial-scale=1.0"/>
HTML:
<div class="html-mobile-background"></div>
CSS:
html {
/* Whatever you want */
}
.html-mobile-background {
position: fixed;
z-index: -1;
top: 0;
left: 0;
width: 100%;
height: 125%; /* To compensate for mobile browser address bar space */
background: url(/images/bg.jpg) no-repeat;
background-size: 100% 100%;
}
#media (min-width: 600px) {
html {
background: url(/images/bg.jpg) no-repeat center center fixed;
background-size: cover;
}
.html-mobile-background {
display: none;
}
}

Answer 3

Galaxy S3 havs a width of greater than 480px in either portrait or landscape view so I don't think those CSS rules will apply. You will need to use 720px.
Try add:
* { background:transparent }
right at the end & move your html { background:... } CSS after that.
This way you can see if there is a mobile footer div or any other element you created that is getting in the way, blocking the view.
Also I would try applying the background CSS to body rather than HTML. Hope you get closer to the answer.

Answer 4

Current solution would be to use viewport height (vh) to indicate the desired height. 100% did not work for Mobile Chrome. CSS:
background-size: cover;
min-height: 100%;