.introduction {
    display: inline-block;
    padding: 20px 30px;
    color: #fff;
    border-radius: 20px;
}

.spec-contents {
    width: 100%;
    margin: 0 auto;
    text-align: center;
    border-collapse: separate;
}

.spec-contents thead th {
    color: #ebebeb;
    background-color: #333;
}

.spec-contents th,
.spec-contents td {
    padding: 5px 20px;
}

@media screen and (min-width: 960px) {
    .spec-contents {
        width: auto;
        min-width: 500px;
        border-spacing: 4px;
    }

    .spec-contents th,
    .spec-contents td {
        background-color: #f6f6f6;
    }

    .spec-contents td {
        text-align: left;
    }
}

@media screen and (max-width: 959px) {
    .spec-contents th,
    .spec-contents td {
        display: block;
    }

    .spec-contents th {
        background-color: #f6f6f6;
    }
}

.line-decoration {
    border-bottom: 3px solid #eee;
}