body {
    background-color: gray;
    
}
main {
    background-color: #f0f8ff;
    border: 4px solid #4169e1;
    padding-left: 10px;
    padding-right: 10px;
}
h1 {
    width: 20em;
    color: #4169e1;
    background-color: #f0f8ff;
    text-align: center;
    border-left: 8px solid red;
    border-right: 8px solid red;
}
h2 {
    border-left: 16px solid #4169e1;
}
dt {
    color: red;
}
img {
    width: 80%;
    height: 80%;
}
ul {
    background-color: gray;
    color: #f0f8ff;
}

@media screen and (max-width: 640px) {
    .ASTfb100 {
        height: auto;
    }
    body {
        background-color: gray;
    }
    main {
        width: auto;
        background-color: #f0f8ff;
        border: 4px solid #4169e1;
        padding-left: 8px;
        padding-right: 8px;
    }
    h1 {
        width: 80%;
        color: #4169e1;
        background-color: #f0f8ff;;
    }
    dt {
        color: red;
    }
    img {
        width: 80%;
        height: 80%;
    }
}