YouTubeからのビデオとオーディオのダウンロード
https://y2mate.com/jp/youtube/-qbvkWoB1B4

/**************************/
/* YouTube の動画 */
/**************************/
.video-container {
    position: relative;
    padding-bottom: 56.25%;
    padding-top: 30px;
    height: 0;
    overflow: hidden;
}
 
.video-container iframe,
.video-container object,
.video-container embed {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 120%;
}
 
/* サムネイル画像をリスト状に並べる（「display-posts」ショートコード対応版）*/
.boxlist ul.display-posts-listing {
    padding-left: 0 !important;
    text-align: left;
}
 
.boxlist ul.display-posts-listing li {
    list-style: none;
    display: inline-block;
    vertical-align: top;
    white-space: normal;
    word-wrap: normal;
    font-size: 12px;
    line-height: 1.2;
    margin: 0;
    padding: 2px;
}
 
.boxlist ul.display-posts-listing li a {
    font-weight: bold;
}
 
#ie7 .boxlist ul.display-posts-listing li {
    display: inline;
    position: relative;
    width: 500px;
}
/*
.boxlist ul.display-posts-listing li img {
    display: block !important;
    border: 1px solid #d0a600 !important;
    width: 80px !important;
    max-width: 100% !important;
    height: auto !important;
    float: left !important;
    margin: -2px 4px 4px 2px !important;
    padding: 2px !important;
}
*/
 
@media (max-width: 767px) {
    .boxlist ul.display-posts-listing li .excerpt {
        width: 93%;
    }
}
 
.boxlist ul.display-posts-listing li .excerpt a {
    font-size: 11px;
    float: right;
}
 
.boxlist.w100 ul.display-posts-listing > li {
    width: 100%;
}
 
.boxlist.w50 ul.display-posts-listing > li {
    width: 45.5%;
    margin-left: 1.5% !important;
}
 
.boxlist.w33 ul.display-posts-listing > li {
    width: 31%;
    margin-left: 1.5% !important;
}
 
@media screen and (max-width : 980px) {
    .boxlist.w33 ul.display-posts-listing > li {
        width: 45.5%;
        margin-left: 1.5% !important;
    }
}
 
@media (max-width: 767px) {
    .boxlist.w50 ul.display-posts-listing > li,.boxlist.w33 ul.display-posts-listing > li {
        width: 100%;
    }
 
    .boxlist.w50 ul.display-posts-listing,.boxlist.w33 ul.display-posts-listing {
        margin: 0 1em 1.625em;
    }
}

/*************************/
/* YouTube の動画 */
/*************************/
.video-container {
    position: relative;
    padding-bottom: 56.25%;
    padding-top: 30px;
    height: 0;
    overflow: hidden;
}
 
.video-container iframe,
.video-container object,
.video-container embed {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

/* サムネイル画像をリスト状に並べる（「display-posts」ショートコード対応版）*/
.boxlist ul.display-posts-listing {
padding-left: 0 !important;
text-align: left;
}

.boxlist ul.display-posts-listing li {
list-style: none;
display: inline-block;
vertical-align: top;
white-space: normal;
word-wrap: normal;
font-size: 12px;
line-height: 1.2;
margin: 0;
padding: 2px;
}

.boxlist ul.display-posts-listing li a {
font-weight: bold;
}

#ie7 .boxlist ul.display-posts-listing li {
display: inline;
position: relative;
width: 500px;
}
/*
.boxlist ul.display-posts-listing li img {
display: block !important;
border: 1px solid #d0a600 !important;
width: 80px !important;
max-width: 100% !important;
height: auto !important;
float: left !important;
margin: -2px 4px 4px 2px !important;
padding: 2px !important;
}
*/

@media (max-width: 767px) {
.boxlist ul.display-posts-listing li .excerpt {
width: 93%;
}
}

.boxlist ul.display-posts-listing li .excerpt a {
font-size: 11px;
float: right;
}

.boxlist.w100 ul.display-posts-listing > li {
width: 100%;
}

.boxlist.w50 ul.display-posts-listing > li {
width: 45.5%;
margin-left: 1.5% !important;
}

.boxlist.w33 ul.display-posts-listing > li {
width: 31%;
margin-left: 1.5% !important;
}

@media screen and (max-width : 980px) {
.boxlist.w33 ul.display-posts-listing > li {
width: 45.5%;
margin-left: 1.5% !important;
}
}

@media (max-width: 767px) {
.boxlist.w50 ul.display-posts-listing > li,.boxlist.w33 ul.display-posts-listing > li {
width: 100%;
}

.boxlist.w50 ul.display-posts-listing,.boxlist.w33 ul.display-posts-listing {
margin: 0 1em 1.625em;
}
}
[/css]

/*************************/
/*************************/
/*************************/
.video-container {
    position: relative;
    padding-bottom: 56.25%;
    padding-top: 30px;
    height: 0;
    overflow: hidden;
}
 
.video-container iframe,
.video-container object,
.video-container embed {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

/*************************/
/*************************/
/*************************/
.video-container {
    position: relative;
    padding-bottom: 56.25%;
    padding-top: 30px;
    height: 0;
    overflow: hidden;
}
 
.video-container iframe,
.video-container object,
.video-container embed {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

 
※ 「padding-bottom:56.25%」の数値を変更すると、縦横の比を変えることができます。

[WordPress] VideoPress や YouTube をタイル状に並べる方法についての検討