/* Fonts */
@import url('https://fonts.googleapis.com/css2?family=Kosugi+Maru&display=swap');
@import url('https://fonts.googleapis.com/css2?family=Kiwi+Maru:wght@300;400;500&display=swap');

html {
    scroll-behavior: smooth;
}

body {
    position: relative;
    margin: 0;
    padding: 0;
    width: 100vw;
    font-family: 'Kosugi Maru', sans-serif;
}

/* デスクトップ & タブレット */
@media screen and (min-width:768px) {

    header {
        position: fixed;
        top: 0;
        box-sizing: border-box;
        margin: 0 auto;
        width: 100vw;
        height: 5vw;
        background-color: #00A0B0;
        z-index: 3;
    }
    
    #menu-navi {
        box-sizing: border-box;
        margin: 0 auto;
        padding: 0 10vw;
        width: 100vw;
        height: 5vw;
    }
    
    #navi-logo {
        float: left;
        width: 25vw;
        height: 5vw;
    }

    #navi-logo > a {
        width: 25vw;
        height: 5vw;
    }

    #navi-logo > a > img {
        float: left;
        width: 5vw;
        height: 5vw;
    }

    #lab-name {
        float: left;
        box-sizing: border-box;
        margin: 0;
        padding: 0;
        width: 20vw;
        height: 5vw;
    }

    #lab-name > p {
        margin: 0 1vw;
        padding: 0;
        width: 18vw;
        height: 2.5vw;
        line-height: 2.5vw;
        font-size: 1.4vw;
        font-weight: bold;
        color: white;
        text-decoration: none;
    }
    
    #insta {
        float: left;
        width: 5vw;
        height: 5vw;
    }
    
    #insta > a > img {
        margin: 1vw;
        width: 3vw;
        height: 3vw;
        filter: invert(100%) sepia(0%) saturate(7492%) hue-rotate(357deg) brightness(91%) contrast(122%);
        /* Reference : https: //codepen.io/sosuke/pen/Pjoqqp */
    }
    
    #menu-bar {
        float: left;
        margin: 0;
        padding: 0;
        width: 50vw;
        height: 5vw;
    }
    
    #sized-box {
        float: left;
        width: 2vw;
        height: 5vw;
    }

    .menu-link {
        text-align: center;
        text-decoration: none;
    }

    .menu {
        float: left;
        box-sizing: border-box;
        text-align: center;
        width: 12vw;
        height: 5vw;
        line-height: 5vw;
        font-size: 1.8vw;
        font-weight: bold;
        color: white;
        list-style-type: none;
    }
    
    .menu-link:visited > .menu {
        color: white;
    }

    .menu-link:hover > .menu {
        color: #002631;
        transition-duration: 1s;
    }

    main {
        box-sizing: border-box;
        margin: 0 auto;
        margin-top: 8vw;
        width: 100vw;
        z-index: 0;
    }

    #sub-navi {
        box-sizing: border-box;
        margin: 3vw auto;
        padding: 0;
        width: 57vw;
        height: 5vw;
    }

    #sub-menu-bar {
        float: left;
        box-sizing: border-box;
        margin: 0;
        padding: 0;
        width: 57vw;
        height: 5vw;
    }
    
    .sub-menu-link {
        text-align: center;
        text-decoration: none;
    }

    .sub-menu-link:hover > .sub-menu {
        color: white;
        background-color: #00A0B0;
        transition-duration: 0.3s;
    }

    .sub-menu-sized-box {
        float: left;
        width: 3vw;
        height: 5vw;
    }

    .sub-menu {
        float: left;
        box-sizing: border-box;
        text-align: center;
        width: 12vw;
        height: 4.6vw;
        line-height: 4.6vw;
        font-size: 1.8vw;
        font-weight: bold;
        color: black;
        border-bottom: 0.4vw solid #00A0B0;
        border-top-left-radius: 1vw;
        border-top-right-radius: 1vw;
        list-style-type: none;
    }

    .category {
        margin: 0 auto;
        padding: 0;
        margin-top: -8vw;
        padding-top: 8vw;
        width: 60vw;
        height: 5vw;
    }

    .category > p {
        margin: 0;
        padding: 0;
        width: 60vw;
        height: 5vw;
        line-height: 5vw;
        font-size: 2.5vw;
        font-family: 'Kiwi Maru', serif;
    }

    .line-box {
        margin: 0 auto;
        width: 60vw;
        height: 0.2vw;
        background-color: #939597;
    }

    #about-lab {
        box-sizing: border-box;
        margin: 0 auto;
        padding: 3vw 0;
        width: 60vw;
        height: 103vw;
    }

    #about-study {
        box-sizing: border-box;
        margin: 0 auto;
        margin-bottom: 3vw;
        padding: 0.5vw 0;
        text-align: left;
        width: 55vw;
        height: 15vw;
        line-height: 3.5vw;
        font-size: 1.4vw;
    }

    #about-study-content {
        margin: 0;
        padding: 0;
    }
    
    #junior,
    #senior {
        box-sizing: border-box;
        text-align: left;
        width: 60vw;
        font-size: 1.4vw;
    }

    #junior {
        margin: 3vw auto;
        height: 32vw;
    }

    #senior {
        margin: 0 auto;
        height: 44vw;
    }

    #junior-title,
    #senior-title {
        box-sizing: border-box;
        margin: 0 auto;
        margin-bottom: 3vw;
        padding: 0;
        text-align: center;
        width: 60vw;
        height: 4vw;
        line-height: 4vw;
        font-size: 1.8vw;
        font-weight: bold;
        color: white;
        border-radius: 5vw;
        background-color: #00A0B0;
    }

    #junior-content-div {
        box-sizing: border-box;
        margin: auto;
        padding: 2vw 1.5vw;
        width: 60vw;
        height: 25vw;
        line-height: 3.2vw;
        border: 0.5vw solid #00A0B0;
        border-radius: 3vw;
        background-color: azure;
    }

    #junior-content {
        margin: 0;
        padding: 0;
    }

    #senior-content-div {
        box-sizing: border-box;
        margin: 0 auto;
        padding: 2vw;
        width: 60vw;
        height: 37vw;
        line-height: 3.2vw;
        border: 0.5vw solid #00A0B0;
        border-radius: 3vw;
        background-color: azure;
    }

    #senior-content1,
    #senior-content2 {
        margin: 0;
        padding: 0;
    }

    #activity-div {
        box-sizing: border-box;
        margin: 0 auto;
        padding: 3vw 0;
        width: 60vw;
        height: 54vw;
    }

    #junior-senior-activity-div {
        box-sizing: border-box;
        margin: 0 0 3vw 0;
        padding: 0;
        width: 60vw;
        height: 48vw;
    }

    #junior-activity-div {
        position: relative;
        box-sizing: border-box;
        margin: 0;
        padding: 0 0 3vw 0;
        width: 60vw;
        height: 18vw;
    }
    #junior-activity-title {
        position: absolute;
        top: -1.5vw;
        left: 4vw;
        margin: 0;
        padding: 0;
        text-align: center;
        width: 25vw;
        height: 4vw;
        line-height: 4vw;
        font-size: 1.8vw;
        color: white;
        border-radius: 5vw;
        background-color: #00A0B0;
    }

    #junior-activity-ul {
        box-sizing: border-box;
        margin: 0;
        padding: 3vw 2.5vw 2vw 2.5vw;
        width: 60vw;
        height: 15vw;
        border: 0.5vw solid #00A0B0;
        border-radius: 3vw;
        background-color: azure;
        list-style: none;
    }

    .junior-activity-li {
        box-sizing: border-box;
        margin: 0;
        padding: 0 2vw;
        width: 27vw;
        height: 3vw;
        line-height: 3vw;
        font-size: 1.4vw;
    }

    .junior-activity-li:nth-of-type(odd) {
        float: left;
    }

    .junior-activity-li:nth-of-type(even) {
        float: left;
    }

    #senior-activity-div {
        position: relative;
        box-sizing: border-box;
        margin: 0;
        padding: 0;
        width: 60vw;
        height: 30vw;
    }

    #senior-activity-title {
        position: absolute;
        top: -1.5vw;
        left: 4vw;
        margin: 0;
        padding: 0;
        text-align: center;
        width: 25vw;
        height: 4vw;
        line-height: 4vw;
        font-size: 1.8vw;
        color: white;
        border-radius: 5vw;
        background-color: #00A0B0;
    }

    #senior-activity-ul {
        box-sizing: border-box;
        margin: 0;
        padding: 3vw 2.5vw 2vw 2.5vw;
        width: 60vw;
        height: 30vw;
        border: 0.5vw solid #00A0B0;
        border-radius: 3vw;
        background-color: azure;
        list-style: none;
    }

    .senior-activity-li {
        box-sizing: border-box;
        margin: 0;
        padding: 0 2.5vw;
        width: 27vw;
        height: 3vw;
        line-height: 3vw;
        font-size: 1.4vw;
    }

    .senior-activity-li:nth-of-type(odd) {
        float: left;
    }

    .senior-activity-li:nth-of-type(even) {
        float: left;
    }

    #sample {
        clear: both;
        margin: 0;
        padding: 0;
        text-align: center;
        width: 54vw;
        height: 3vw;
        line-height: 3vw;
        font-size: 1.4vw;
        color: #00A0B0;
    }

    #sample-title {
        margin: 0;
        padding: 0;
        text-align: center;
        width: 54vw;
        height: 3vw;
        line-height: 3vw;
        font-size: 1.4vw;
        font-weight: bold;
    }

    .sample-li {
        box-sizing: border-box;
        margin: 0;
        padding: 0 2.5vw;
        width: 54vw;
        height: 3vw;
        line-height: 3vw;
        font-size: 1.4vw;
    }

    #camp-div {
        position: relative;
        box-sizing: border-box;
        margin: 0;
        padding: 0;
        width: 60vw;
        height: 82vw;
    }

    #camp-title {
        position: absolute;
        box-sizing: border-box;
        top: -1.5vw;
        left: 4vw;
        margin: 0;
        padding: 0;
        text-align: center;
        width: 25vw;
        height: 4vw;
        line-height: 4vw;
        font-size: 1.8vw;
        color: white;
        border-radius: 5vw;
        background-color: #00A0B0;
    }

    #camp-ul {
        box-sizing: border-box;
        margin: 0;
        padding: 3vw 2vw 2vw 2vw;
        width: 61vw;
        height: 79vw;
        border: 0.5vw solid #00A0B0;
        border-radius: 3vw;
        background-color: azure;
        list-style: none;
    }

    .camp-li {
        box-sizing: border-box;
        margin: 0;
        padding: 0;
        width: 25vw;
        height: 4vw;
        line-height: 4vw;
        font-size: 1.4vw;
    }

    .camp-li:nth-child(1),
    .camp-li:nth-child(5),
    .camp-li:nth-child(9) {
        font-weight: bold;
    }

    .camp-li:nth-child(4),
    .camp-li:nth-child(8) {
        float: right;
    }

    #entry-div {
        box-sizing: border-box;
        margin: 0 auto;
        padding: 3vw 0;
        width: 60vw;
        height: 42vw;
    }

    .entry-content {
        margin: 0 auto;
        padding: 0;
        text-align: center;
        width: 40vw;
        height: 4vw;
        line-height: 4vw;
        font-size: 1.6vw;
        color: white;
        border-radius: 5vw;
        background-color: #00A0B0;
    }

    .down-arrow {
        margin: 0 auto;
        padding: 0;
        text-align: center;
        width: 40vw;
        height: 4vw;
        line-height: 4vw;
        font-size: 1.6vw;
        color: #00A0B0;
    }

    #youtube-div {
        box-sizing: border-box;
        margin: 0 auto;
        margin-bottom: 3vw;
        padding: 3vw 0;
        width: 60vw;
        height: 92vw;
    }

    .youtube-title {
        box-sizing: border-box;
        margin: 0 auto;
        margin-bottom: 3vw;
        padding: 0;
        text-align: center;
        width: 40vw;
        height: 4vw;
        line-height: 4vw;
        font-size: 1.8vw;
        font-weight: bold;
        color: white;
        border-radius: 5vw;
        background-color: #00A0B0;
    }

    .youtube-title > p {
        margin: 0;
        padding: 0;
    }

    .inform-content-div {
        box-sizing: border-box;
        margin: 3vw auto;
        padding: 2vw 5vw;
        text-align: center;
        width: 60vw;
        height: 36vw;
        font-size: 1.4vw;
        border: 0.5vw solid #00A0B0;
        border-radius: 3vw;
        background-color: azure;
    }

    .youtube-inform {
        margin-bottom: 1vw;
    }

    .youtube-inform > p {
        margin: 0;
        padding: 0;
        width: 49vw;
        height: 3vw;
        line-height: 3vw;
    }

    .inform-content-div > iframe {
        width: 49vw;
        height: 27vw;
        border-radius: 3vw;
    }

    #top-button {
        position: fixed;
        bottom: 5vw;
        right: 5vw;
        box-sizing: border-box;
        padding: 0.5vw;
        width: 6vw;
        height: 6vw;
        border-radius: 1vw;
        background-color: #00A0B0;
        cursor: pointer;
    }

    #top-button > p {
        box-sizing: border-box;
        margin: 0;
        padding: 0;
        text-align: center;
        width: 5vw;
        height: 2.5vw;
        line-height: 1.5vw;
        font-size: 1.5vw;
        color: white;
    }

    #top-button > p:last-child {
        font-size: 1.8vw;
    }

    #top-button:hover > p {
        color: black;
        transition-duration: 1s;
    }

    footer {
        box-sizing: border-box;
        margin: 0 auto;
        text-align: center;
        width: 100vw;
        height: 4vw;
        line-height: 4vw;
        background-color: #00A0B0;
    }

    footer > p {
        margin: 0;
        font-size: 1.5vw;
        color: white;
    }

}

/* モバイル */
@media screen and (max-width:767px) {

    header {
        width: 100vw;
        height: 27vw;
        background-color: #00A0B0;
    }

    #menu-navi {
        box-sizing: border-box;
        width: 100vw;
        height: 27vw;
    }

    #navi-logo {
        float: left;
        margin: 0;
        margin-right: 16vw;
        margin-bottom: 1.3vw;
        width: 70vw;
        height: 16vw;
    }
    
    #navi-logo > a {
        width: 70vw;
        height: 16vw;
    }
    
    #navi-logo > a > img {
        float: left;
        width: 16vw;
        height: 16vw;
    }
    
    #lab-name {
        box-sizing: border-box;
        float: left;
        margin: 0;
        padding: 1vw 0;
        width: 54vw;
        height: 16vw;
    }
    
    #lab-name > p {
        margin: 0;
        padding: 0;
        width: 54vw;
        height: 7vw;
        line-height: 7vw;
        font-size: 4vw;
        font-weight: bold;
        color: white;
        text-decoration: none;
    }
    
    #insta {
        float: left;
        box-sizing: border-box;
        margin: 0;
        margin-bottom: 1.3vw;
        padding: 2.5vw 0;
        width: 12vw;
        height: 16vw;
    }

    #insta > a > img {
        width: 11vw;
        height: 11vw;
        filter: invert(100%) sepia(0%) saturate(7492%) hue-rotate(357deg) brightness(91%) contrast(122%);
        /* Reference : https: //codepen.io/sosuke/pen/Pjoqqp */
    }
    
    #menu-bar {
        clear: both;
        box-sizing: border-box;
        margin: 0;
        padding: 0;
        width: 100vw;
        height: 9.7vw;
    }
    
    .menu-link {
        text-align: center;
        text-decoration: none;
    }
    
    #sized-box {
        margin: 0 auto;
        margin-bottom: 1.3vw;
        padding: 0;
        width: 90vw;
        height: 0.4vw;
        background-color: white;
    }

    .menu {
        float: left;
        box-sizing: border-box;
        margin: 0.35vw 0 1.65vw 0;
        text-align: center;
        width: 25vw;
        height: 6vw;
        line-height: 6vw;
        font-size: 3vw;
        font-weight: bold;
        color: white;
        list-style-type: none;
    }
    
    .menu-link:visited > .menu {
        color: white;
    }
    
    .menu-link:hover > .menu {
        transition-duration: 1s;
        color: #002631;
    }

    main {
        box-sizing: border-box;
        margin: 0 auto;
        width: 100vw;
        z-index: 0;
    }

    #sub-navi {
        box-sizing: border-box;
        margin: 5vw auto;
        padding: 0;
        width: 90vw;
        height: 8vw;
    }

    #sub-menu-bar {
        float: left;
        box-sizing: border-box;
        margin: 0;
        padding: 0;
        width: 87vw;
        height: 8vw;
    }
    
    .sub-menu-link {
        text-align: center;
        text-decoration: none;
        -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
    }
    
    .sub-menu {
        float: left;
        box-sizing: border-box;
        text-align: center;
        width: 18vw;
        height: 7.5vw;
        line-height: 7.5vw;
        font-size: 3vw;
        font-weight: bold;
        color: black;
        border-bottom: 0.5vw solid #00A0B0;
        border-top-left-radius: 1vw;
        border-top-right-radius: 1vw;
        list-style-type: none;
    }

    @media screen and (min-width:500px) {
        .sub-menu-link:hover>.sub-menu {
            color: white;
            background-color: #00A0B0;
            transition-duration: 0.5s;
        }
    }
    
    .sub-menu-sized-box {
        float: left;
        width: 5vw;
        height: 8vw;
    }
    
    .category {
        margin: 0 auto;
        padding: 0;
        width: 90vw;
        height: 12vw;
    }

    .category > p {
        margin: 0;
        padding: 0;
        width: 80vw;
        height: 12vw;
        line-height: 12vw;
        font-size: 5vw;
        font-family: 'Kiwi Maru', serif;
    }

    .line-box {
        margin: 0 auto;
        width: 90vw;
        height: 0.4vw;
        background-color: #939597;
    }

    #about-lab {
        box-sizing: border-box;
        margin: 0 auto;
        padding: 5vw 0;
        width: 90vw;
        height: 224vw;
    }

    #about-study {
        box-sizing: border-box;
        margin: 0 auto;
        padding: 0;
        text-align: center;
        width: 80vw;
        height: 35vw;
        line-height: 5vw;
        font-size: 3.5vw;
    }

    #about-study-content {
        margin: 0;
        padding: 0;
    }
    
    #junior,
    #senior {
        box-sizing: border-box;
        text-align: left;
        width: 91vw;
        font-size: 3.5vw;
    }

    #junior {
        margin: 5vw auto;
        height: 67vw;
    }

    #senior {
        margin: 0 auto;
        height: 102vw;
    }

    #junior-title,
    #senior-title {
        box-sizing: border-box;
        margin: 0 auto;
        margin-bottom: 5vw;
        padding: 0;
        text-align: center;
        width: 80vw;
        height: 7vw;
        line-height: 7vw;
        font-size: 4vw;
        font-weight: bold;
        color: white;
        border-radius: 5vw;
        background-color: #00A0B0;
    }

    #junior-content-div {
        box-sizing: border-box;
        margin: 0 auto;
        padding: 2vw;
        width: 91vw;
        height: 55vw;
        line-height: 5vw;
        border: 0.5vw solid #00A0B0;
        border-radius: 3vw;
        background-color: azure;
    }

    #junior-content {
        margin: 0;
        padding: 0;
    }

    #senior-content-div {
        box-sizing: border-box;
        margin: 0 auto;
        padding: 2vw;
        width: 91vw;
        height: 90vw;
        line-height: 5vw;
        border: 0.5vw solid #00A0B0;
        border-radius: 3vw;
        background-color: azure;
    }

    #senior-content1,
    #senior-content2 {
        margin: 0;
        padding: 0;
    }

    #senior-content1 {
        margin-bottom: 5vw;
    }

    #activity-div {
        box-sizing: border-box;
        margin: 0 auto;
        padding: 5vw 0;
        width: 90vw;
        height: 178vw;
    }

    #junior-senior-activity-div {
        box-sizing: border-box;
        margin: 0;
        margin-bottom: 5vw;
        padding: 0;
        width: 90vw;
        height: 169vw;
    }

    #junior-activity-div {
        box-sizing: border-box;
        margin: 0;
        margin-bottom: 5vw;
        padding: 0;
        width: 90vw;
        height: 59vw;
    }

    #junior-activity-title {
        box-sizing: border-box;
        margin: 0 auto;
        margin-bottom: 5vw;
        padding: 0;
        text-align: center;
        width: 80vw;
        height: 7vw;
        line-height: 7vw;
        font-size: 4vw;
        font-weight: bold;
        color: white;
        border-radius: 5vw;
        background-color: #00A0B0;
    }

    #junior-activity-ul {
        box-sizing: border-box;
        margin: 0;
        padding: 5vw 6vw;
        width: 90vw;
        height: 47vw;
        border: 0.5vw solid #00A0B0;
        border-radius: 3vw;
        background-color: azure;
        list-style: none;
    }

    .junior-activity-li {
        box-sizing: border-box;
        margin: 0;
        padding: 0 4vw;
        width: 77vw;
        height: 6vw;
        line-height: 6vw;
        font-size: 4vw;
    }

    #senior-activity-div {
        box-sizing: border-box;
        margin: 0;
        padding: 0;
        width: 90vw;
        height: 105vw;
    }

    #senior-activity-title {
        box-sizing: border-box;
        margin: 0 auto;
        margin-bottom: 5vw;
        padding: 0;
        text-align: center;
        width: 80vw;
        height: 7vw;
        line-height: 7vw;
        font-size: 4vw;
        font-weight: bold;
        color: white;
        border-radius: 5vw;
        background-color: #00A0B0;
    }

    #senior-activity-ul {
        box-sizing: border-box;
        margin: 0;
        padding: 5vw 6vw;
        width: 90vw;
        height: 93vw;
        border: 0.5vw solid #00A0B0;
        border-radius: 3vw;
        background-color: azure;
        list-style: none;
    }

    .senior-activity-li {
        box-sizing: border-box;
        margin: 0;
        padding: 0 4vw;
        width: 77vw;
        height: 6vw;
        line-height: 6vw;
        font-size: 4vw;
    }

    #sample {
        box-sizing: border-box;
        margin: 0;
        padding: 0;
        text-align: center;
        width: 77vw;
        height: 8vw;
        line-height: 8vw;
        font-size: 4vw;
        font-weight: bold;
        color: #00A0B0;
    }

    #sample-title {
        box-sizing: border-box;
        margin: 0;
        padding: 0;
        text-align: center;
        width: 77vw;
        height: 8vw;
        line-height: 8vw;
        font-size: 4vw;
        font-weight: bold;
    }

    .sample-li {
        box-sizing: border-box;
        margin: 0;
        padding: 0 4vw;
        width: 77vw;
        height: 12vw;
        line-height: 6vw;
        font-size: 4vw;
    }

    #camp-div {
        box-sizing: border-box;
        margin: 0;
        margin-bottom: 5vw;
        padding: 0;
        width: 90vw;
        height: 115vw;
    }

    #camp-title {
        box-sizing: border-box;
        margin: 0 auto;
        margin-bottom: 5vw;
        padding: 0;
        text-align: center;
        width: 80vw;
        height: 7vw;
        line-height: 7vw;
        font-size: 4vw;
        font-weight: bold;
        color: white;
        border-radius: 5vw;
        background-color: #00A0B0;
    }

    #camp-ul {
        box-sizing: border-box;
        margin: 0;
        padding: 5vw 6vw;
        width: 90vw;
        height: 103vw;
        border: 0.5vw solid #00A0B0;
        border-radius: 3vw;
        background-color: azure;
        list-style: none;
    }

    .camp-li {
        box-sizing: border-box;
        margin: 0;
        padding: 0 4vw;
        width: 77vw;
        height: 6vw;
        line-height: 6vw;
        font-size: 4vw;
    }

    .camp-li:nth-child(1),
    .camp-li:nth-child(5),
    .camp-li:nth-child(9) {
        font-weight: bold;
    }

    .camp-li:nth-child(4),
    .camp-li:nth-child(8) {
        margin-bottom: 10vw;
    }

    #entry-div {
        box-sizing: border-box;
        margin: 0 auto;
        padding: 5vw 0;
        width: 90vw;
        height: 82vw;
    }

    .entry-content {
        margin: 0 auto;
        padding: 0;
        text-align: center;
        width: 80vw;
        height: 8vw;
        line-height: 8vw;
        font-size: 4vw;
        color: white;
        border-radius: 5vw;
        background-color: #00A0B0;
    }

    .down-arrow {
        margin: 0 auto;
        padding: 0;
        text-align: center;
        width: 80vw;
        height: 8vw;
        line-height: 8vw;
        font-size: 4vw;
        color: #00A0B0;
    }

    #youtube-div {
        box-sizing: border-box;
        margin: 0 auto;
        padding: 5vw 0;
        width: 91vw;
        height: 173vw;
    }

    .youtube-title {
        box-sizing: border-box;
        margin: 0 auto;
        padding: 0;
        text-align: center;
        width: 80vw;
        height: 7vw;
        line-height: 7vw;
        font-size: 4vw;
        font-weight: bold;
        color: white;
        border-radius: 5vw;
        background-color: #00A0B0;
    }

    .youtube-title > p {
        margin: 0;
        padding: 0;
    }

    .inform-content-div {
        box-sizing: border-box;
        margin: 5vw auto;
        padding: 5vw;
        text-align: center;
        width: 91vw;
        height: 67vw;
        font-size: 3vw;
        border: 0.5vw solid #00A0B0;
        border-radius: 3vw;
        background-color: azure;
    }

    .inform-content-div:last-of-type {
        margin-bottom: 0;
    }

    .youtube-inform > p {
        margin: 0 auto;
        margin-bottom: 5vw;
        padding: 0;
        width: 80vw;
        height: 6vw;
        line-height: 6vw;
    }

    .inform-content-div > iframe {
        width: 80vw;
        height: 45vw;
        border-radius: 3vw;
    }

    #top-button {
        position: fixed;
        bottom: 8vw;
        right: 8vw;
        box-sizing: border-box;
        padding: 0.5vw;
        width: 11vw;
        height: 11vw;
        border-radius: 2vw;
        background-color: #00A0B0;
        cursor: pointer;
    }

    #top-button > p {
        box-sizing: border-box;
        margin: 0;
        padding: 0;
        text-align: center;
        width: 10vw;
        height: 5vw;
        line-height: 4vw;
        font-size: 4vw;
        color: white;
    }

    #top-button > p:last-child {
        font-size: 3vw;
    }

    @media screen and (min-width:500px) {
        #top-button:hover > p {
            color: black;
            transition-duration: 1s;
        }
    }

    footer {
        box-sizing: border-box;
        margin: 0 auto;
        text-align: center;
        width: 100vw;
        height: 10vw;
        line-height: 10vw;
        background-color: #00A0B0;
    }
    
    footer > p {
        margin: 0;
        font-size: 3vw;
        color: white;
    }

}

/* 
    1. position
    2. top/bottom
    3. left/right
    4. float/clear
    5. display
    6. box-sizing
    7. margin
    8. padding
    9. text-align
    10. width
    11. height
    12. line-height
    13. font-size
    14. font-weight
    15. font-family
    16. color
    17. border
    18. border-radius
    19. background-color
    20. cursor
    21. text-decoration
    22. list-style-type
    23. transition-duration
    24. z-index
    25. etc.
*/