doylet.dev/luneaustralia/style.css

* {
    margin: 0px;
    padding: 0px;
    box-sizing: border-box;
    font-family: 'Lato', sans-serif;
}

body {
    background-size: 100% auto;
    background-repeat: no-repeat;
    background-image: url("images/background.png");
    background-color: rgba(195, 232, 255, 1.0);
}

/**
 * NAVIGATION
 */

nav {
    max-height: 200px;
    text-align: center;
    padding: 25px 0px;
    /*background-color: rgba(0, 0, 0, 0.1);*/
}

nav img {
    height: 100%;
}

/**
 * HEADER
 */

header {
    min-width: 100%;
    /*min-height: 100%;*/
/*    background-size: contain;
    background-repeat: repeat no-repeat;
    background-image: url("images/header_bg.jpg");*/
}

#header_wrapper {
    max-width: 960px;
    margin: 0px auto;
    padding: 20px 0px;
}

#math_masher_logo {
    width: 100%;
    padding: 0px 20px;
    margin: 10px 0px;
}

@media only screen and (min-width: 768px) {
    #math_masher_logo {
        width: 100%;
        padding: 25px 60px;
    }
}

/* STORE */

#store_wrapper {
    width: 50%;
    margin: 0 auto;
}

#app_store, #play_store {
    width: 100%;
    padding: 10px;
}

#lune_logo {
	height: 150px;
	margin: auto;
}

#app_store:hover, #play_store:hover, #fb_logo:hover {
    transform: scale(1.1);
}

@media only screen and (min-width: 768px) {
    #app_store, #play_store {
        padding: 25px;
    }

    .game_play:hover {
        transform: scale(1.1);
    }

    #store_wrapper {
        width: 80%;
        margin: 0px auto;
    }
}

/**
 * MAIN
 */

main {
    max-width: 960px;
    margin: 20px auto;
    clear: both;
}

/* TRAILER */
#trailer_wrapper {
    position: relative;
    padding-bottom: 56.25%;
    margin: 0px 0px 25px 0px;
}

#trailer_wrapper iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    padding: 0px 20px;
}

#math_masher_desc {
    width: 80%;
    padding: 0px 0px;
    margin: 20px auto;
    text-align: center;
    background-color: rgba(255, 255, 255, 0.9);
    color: rgba(0, 0, 0, 0.7);
    text-align: left;
    box-shadow: 2px 2px 2px 1px rgba(0, 0, 0, 0.2);
}

#math_masher_desc p, li, ul{
    margin: 10px 0px;
    padding: 0px 20px;
}

#math_masher_desc li {
    list-style-type: none;
}

@media only screen and (min-width: 768px) {
    #math_masher_desc {
        /*padding: 0px 150px;*/
    }
}

#game_play_wrapper .col-4 {
    margin: 10px 0px 10px 0px;
}

@media only screen and (min-width: 768px) {
    #game_play_wrapper {
        margin: 25px 0px 0px 0px;
        width: 100%;
    }
}

.game_play {
    width: 90%;
    margin: 0px 20px;
    box-shadow: 2px 2px 2px 1px rgba(0, 0, 0, 0.2);
}

/**
 * FOOTER
 */

footer {
    clear: both;
    text-align: center;
    margin: 50px auto 0px auto;
    /*background-color: rgba(0, 0, 0, 0.1);*/
}

#footer_wrapper {
    border-top: solid 1px black;
    padding: 25px 0px;
    max-width: 960px;
    margin: 0px auto;
}

#email {
    margin-top: 25px;
}

#email a:link {
    color: black;
    text-decoration: none;
}

#copyright {
    margin-top: 30px;
}

#fb_logo {
    width: 5%;
    margin-top: 10px;
}

#email a:hover {
    color: red;
}

/**
 * Grid-View
 * https://www.w3schools.com/css/css_rwd_mediaqueries.asp
 */
/* For mobile phones: */
[class*="col-"] {
    width: 100%;
}

@media only screen and (min-width: 768px) {
    /* For desktop: */
    .col-1 {width: 8.33%;}
    .col-2 {width: 16.66%;}
    .col-3 {width: 25%;}
    .col-4 {width: 33.33%;}
    .col-5 {width: 41.66%;}
    .col-6 {width: 50%;}
    .col-7 {width: 58.33%;}
    .col-8 {width: 66.66%;}
    .col-9 {width: 75%;}
    .col-10 {width: 83.33%;}
    .col-11 {width: 91.66%;}
    .col-12 {width: 100%;}
}

[class*="col-"] {
    float: left;
}

.row::after {
    content: "";
    clear: both;
    display: table;
}