* {
    margin: 0;
    padding: 0;
    border: 0;
}

html {
    height: 100dvh;
    font-size: 1.2vw;
}

main {
    height: 80vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}
body {
    background: linear-gradient(indianred, yellow);
}

#startButton {
    background-color: salmon;
    width: 40vh;
    height: 10vh;
    font-size: 300%;
    font-family: "Comic Sans MS", display;
    border-radius: 1rem;
    border: black solid 0.05rem;
    margin: 0.5rem;
    transition: background-color 0.4s ease;
}

#startButton:hover {
    background-color: lightgoldenrodyellow;
}

#anchor {
    position: absolute;
    margin-top: 30%;
}

img {
    width : 50%;
}

#warning {
    display: none;
    position:fixed;
    top:0;
    left:0;
    width:100vw;
    height:100vh;
    background:gray;
    font-size: 5rem;
    z-index: 1000;
    text-align:center;
    padding-top:50vh;
}

@media screen and (orientation: portrait) {
    .rotate-warning {
        display: block;
    }
}

@media screen and (orientation: landscape) {
    .rotate-warning {
        display: none;
    }
}