*{box-sizing:border-box;margin:0;padding:0;font-family:Fira Sans,sans-serif}::selection{background:#42b88380}body{background-color:#35495e}a{text-decoration:none}header{background-color:#2c3d4e;justify-content:center;align-items:center;padding:10px 16px;display:flex;position:relative;box-shadow:0 0 6px #0000001a}header .back-btn{color:#fff;cursor:pointer;background-color:#0000;border:1px solid #496583;border-radius:6px;padding:6px 12px;font-size:14px;transition:all .3s;position:absolute;left:16px}header .back-btn:hover{background-color:#496583}h1{color:#fff;font-size:28px}h1 span{color:#42b883}