style.css

body {
    font-family: 'Allerta Stencil', sans-serif;
    font-weight: 400;
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    text-shadow: .1em .1em 0 rgba(0,0,0,0.3);
    font-size: 1.3em;
    height: 100vh;
    background-image: linear-gradient(to right top, #99bbcb, #a5c7d7, #b1d4e2, #bde0ee, #c9edfa);
}
h1 {
    margin: 0 auto;
    font-size: 2.2em;
    text-align: center;
    color: #fff;
    font-family: 'Allerta Stencil', sans-serif;
    font-size: 5em;
}
body.sunny {
    
    background-image: linear-gradient(to right top, #ff4e50, #ff713e, #ff932b, #ffb41d, #f9d423);
}
body.cloudy {
    background-image: linear-gradient(to right top, #63747c, #71858e, #7f96a0, #8da8b2, #9bbac5);
}
body.rainy {
    background-image: linear-gradient(to right top, #637c7b, #718e8c, #7ea09e, #8db2b0, #9bc5c3);
}