style.css

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

body {
    display: flex;
    justify-content: center;
    height: 100vh;
    background: linear-gradient(rgba(0,0,0,0.5),rgba(0,0,0,0.5)),url("https://images.unsplash.com/photo-1518621543355-240e849eadcc?ixlib=rb-1.2.1&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=1470&q=80");
    background-size: cover;
    background-repeat: no-repeat;
    background-position: center;  
}

.container {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    height: 100%;
    padding: 0 10px;
}

.content {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.header {
    color: white;
    margin-bottom: 20px;
    font-weight: 300;
    text-align: center;
}

a {
    text-decoration: none;
    color: white;
    text-align: center;
    font-weight: 300;
}

.btn {
    background-color: transparent;
    border: 1px solid white;
    padding: 5px 25px;
    margin: 10px;
    font-size: 14px;
    width: 50%;
}

.btn:hover {
    cursor: pointer;
    box-shadow: 0 0.4rem 1.4rem 0 rgba(255, 255, 255, 0.5);
    transform: translate(-0.1rem);
    transition: transform 150ms;
}