body {
    background-color: azure;
    font-family: "メイリオ", "ＭＳ Ｐゴシック", sans-serif;
}

#container {
    max-width: 960px;
    width: 100%;
    margin: 0 auto;
    background-color: #fff;
}

header {
    padding-top: 34%;
    background-image: url(../img/gendai.jpg);
    background-repeat: no-repeat;
    background-size: cover;
    margin-bottom: 20px;
}

header h1 {
    margin-top: -20%;
    text-align: center;
    color: brown;
    text-shadow:
        2px 2px 2px #fff,
        -2px 2px 2px #fff,
        2px -2px 2px #fff,
        -2px -2px 2px #fff;
}

main {
    width: 100%;
    box-sizing: border-box;
    padding: 5px;
}

ul {
    margin: 0;
    padding: 0;
}

li {
    display: inline-block;
    list-style-type: none;
    width: 49.5%;
}

li a {
    color: #333;
    border: 1px solid #333;
    border-radius: 10px;
    display: block;
    text-decoration: none;
    line-height: 70px;
    height: 70px;
    margin: 10px 0;
    padding-left: 5%;
    background-color: aliceblue;
}

[name="soon"] {
    background-color: darkgray;
    pointer-events: none;
}

footer {
    text-align: center;
    color: #ff9380;
    margin: 20px 0;
}

@media screen and (max-width: 540px) {
    li {
        display: block;
        width: 100%;
    }
}