CSS

@import url(http://fonts.googleapis.com/css?family=Audiowide);
//mixins
@mixin bp($bp, $min-max: min-width) {
    $em: $bp/16;
    @media(#{$min-max}: #{$em}em) {
        @content;
    }
}

html {
    box-sizing: border-box;
    font-family: Arial, sans-serif;
    font-size: 16px; 
    font-weight: normal;
    line-height: 1.4;
}

*,
*:before,
*:after  { box-sizing: inherit; }

h1 { 
    color: #fff;
    font-family: "Audiowide", cursive;
    font-size: 2em;
    font-size: 6vw;
    line-height: 1.2;
    margin: 0.5em 0 3em;
    text-shadow: 1px 1px 1px #333;
}

@include bp(1075) { h1 { font-size: 4em; } }

html,
body {
    height: 100%;
    width: 100%;
    margin: 0;
    padding: 0;
}

.wrap {
    height: 100%;
    width: 100%;
    position: relative;
    overflow: hidden;
    background: #120103;
    color: #fff;
    text-align: center;
}

header {
    background: #3E474F;
    box-shadow: 0 .5em 1em #111;
    position: absolute;
    top: 0;
    left: 0;
    z-index: 900;
    width: 100%;

    label {
        color: #788188;
        cursor: pointer;
        display: inline-block;
        line-height: 4.25em;
        font-size: .75em;
        font-weight: bold;
        padding: 0 1em;
    }
}

header label:hover {
    background: #2e353b;
}

.slide {
    height: 100%;
    width: 100%;
    position: absolute;
    top: 0;
    left: 100%;
    z-index: 10;
    padding:  8em 1em 0;
    background-color: #120103;
    background-position: 50% 50%;
    background-size: cover;
    transition: left 0s .75s;        

    &-one { background-image: url('https://s3-us-west-2.amazonaws.com/s.cdpn.io/65463/starryFarm.jpg'); }

    &-two { background-image: url('https://s3-us-west-2.amazonaws.com/s.cdpn.io/65463/campusDarkDays.jpg'); }

    &-three { background-image: url('https://s3-us-west-2.amazonaws.com/s.cdpn.io/65463/autumn.jpg'); }

    &-four { background-image: url('https://s3-us-west-2.amazonaws.com/s.cdpn.io/65463/lakehouse.jpg'); }

    h1 {
        opacity: 0;
        transform: translateY(100%);
        transition: transform .5s .5s, opacity .5s;
    }
}

[id^="slide"]:checked + .slide {
    left: 0;
    z-index: 100;
    transition: left .65s ease-out;

    & h1 {
        opacity: 1;
        transform: translateY(0);
        transition: all .5s .5s;
    }
}