.youtube {
    position: relative;
    width: 100%;
    padding-top: 56.25%;
}

.youtube iframe {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
}
div.product__explain ul li {
  position: relative;
    margin-left: 20px;
}
div.product__explain ul li::after {
  display: block;
  content: '';
  position: absolute;
  top: .6em;
  left: -1em;
  width: 4px;
  height: 4px;
  background-color: #666;
  border-radius: 100%;
}

div.product__explain h2,
div.product__explain h3,
div.product__explain h4,
div.product__explain h5,
div.product__explain h6 {
    font-weight: 600;
    color: #393939;
}

div.product__explain h2 {
    position: relative;
    padding-bottom: 0.5em;
    border-bottom: 4px solid #DDD;
}

div.product__explain h2::after {
    position: absolute;
    content: " ";
    border-bottom: solid 4px #446689;
    bottom: -4px;
    width: 10%;
    display: block;
}

div.product__explain h3 {
    position: relative;
    padding: 0 0 0.5em 0.7em;
    border-bottom: 1px solid black;
}

div.product__explain h3::after {
    position: absolute;
    top: 0.2em;
    left: 0;
    content: '';
    width: 5px;
    height: 1em;
    background-color: #446689;
}

div.product__explain h4 {
    position: relative;
    padding-left: 1.2em;
}

div.product__explain h4::after {
    position: absolute;
    top: 50%;
    left: 0;
    transform: translateY(-50%);
    content: '';
    width: 12px;
    height: 4px;
    background-color: #446689;
}

div.product__explain p {
    margin: 1.2em 0 1.2em;
}

.maker_link {
    width: auto;
    display: inline-block;
    margin: 20px 0 20px;
    padding: 0.5em 1em;
    text-decoration: none;
    text-align: center;
    background: #f7f7f7;
    border-left: solid 6px #ff7c5c;
    /*左線*/
    color: #ff7c5c;
    /*文字色*/
    font-weight: bold;
    box-shadow: 0px 2px 2px rgba(0, 0, 0, 0.29);
}

.maker_link:active {
    box-shadow: inset 0 0 2px rgba(128, 128, 128, 0.1);
    transform: translateY(2px);
}

.maker_link a {
    display: block;
    width: 100%;
    height: 100%;
    color: #ff7c5c;
}

.manual_link {
    width: auto;
    display: inline-block;
    margin: 20px 0 20px;
    padding: 0.5em 1em;
    text-decoration: none;
    text-align: center;
    background: #f7f7f7;
    border-left: solid 6px #990033;
    /*左線*/
    color: #990033;
    /*文字色*/
    font-weight: bold;
    box-shadow: 0px 2px 2px rgba(0, 0, 0, 0.29);
}

.manual_link:active {
    box-shadow: inset 0 0 2px rgba(128, 128, 128, 0.1);
    transform: translateY(2px);
}

.manual_link a {
    display: block;
    width: 100%;
    height: 100%;
    color: #990033;
}

div.product__explain table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px auto;
}

div.product__explain td,
th {
    padding: 10px;
    border-bottom: 1px solid #ccc;
}

div.product__explain th {
    color: #fff;
    background: #005ab3;
}

div.product__explain table tr td:nth-child(odd) {
    background: #f7f7f7;
}

div.product__explain table tr td:first-child {
    width: 26%;
}
p.note_text {
    color: firebrick;
}