@import url('https://fonts.googleapis.com/css?family=Open+Sans:300,800&display=swap');
body{background:url(../imgs/background.jpg) no-repeat fixed center; background-size:cover; font:14px 'Open Sans', sans-serif;}

.height-container{display:flex; flex-direction:column; min-height:100vh;}

header{padding:20px 0; flex:1;}

.content-main{padding:50px 0; text-align:center; background:url(../imgs/pattern-bg.png); color:#fff;}
.content-main h4{font-size:18px;}
.content-main .btn{background:#29e7d6; border:1px solid #29e7d6; font-weight:800; color:#111; text-transform:uppercase; padding-left:20px; transition:all 200ms;}
.content-main .btn .fas{position:relative; left:-20px; opacity:0; transition:all 500ms;}
.content-main .btn:hover{background:transparent; color:#fff; border-color:#fff;}
.content-main .btn:hover .fas{left:0; opacity:1;}