.contents{
    margin: 0;
}
#con_bg{
    content: '';
    position: absolute;
    width: 100%;
    height: 100vh;
    background-color: black;
    z-index: -1;
    clip-path: polygon(0 0,100% 0,100% 100%,0 100%);
    -webkit-animation: bg-animation 2s cubic-bezier(0.39, 0.07, 0.15, 1) both;
    animation: bg-animation 2s cubic-bezier(0.39, 0.07, 0.15, 1) both;
}


section{
    width: 100%;
    min-height: calc(100vh - 240px);
    margin-bottom: 180px;
    box-sizing: border-box;
}
.dt_con{
    width: 100%;
    margin: 0;
    margin-top: 100px;
    padding: 0%;
    text-align: center;
}
.dt_con h1{
    font-family: broadacre-medium-0, ryo-gothic-plusn, sans-serif;
    font-size: calc(18pt + 2.5vw);
    animation: translate-in2 2s cubic-bezier(0.39, 0.07, 0.15, 1) both;
    line-height: 40px;
}
.dt_con h1 span#sub{
    font-size: 0.66em;
}
.dt_con h1 span#sub small{
    font-size: 0.66em;
}

.dt_con .comment{
    padding-top: 30px;
    margin: auto;
    font-size: 0.9em;
    max-width: 600px;
    width: 90%;
}
.comment span{
    font-weight: bold;
}

#design-thumb {
    width: 70vw;
    max-width: 800px;
    animation: translate-in 2s cubic-bezier(0.39, 0.07, 0.15, 1) both 0.25s;
    margin-top: 30px;
}

#youtube, #niconico{
    display: inline-block;
    width: 70vw;
    max-width: 800px;
    height: calc(70vw / 16 * 9);
    max-height: calc(800px /16 * 9);
    animation: translate-in 2s cubic-bezier(0.39, 0.07, 0.15, 1) both 0.25s;
    margin-top: 30px;
}
.twitter-tweet{
    width: 100%;
    animation: translate-in 2s cubic-bezier(0.39, 0.07, 0.15, 1) both 0.25s;
    margin-top: 30px;
    margin: auto;
}
.caption{
    color: #868686;
    font-size: 1em;
    animation: translate-in 2s cubic-bezier(0.39, 0.07, 0.15, 1) both 0.5s;
}
#credit, #overview, .comment{
    color: #868686;
    font-size: 1.2em;
    width: 100%;
    margin-top: calc(40px + 3vw);
    line-height: 1.8em;
    animation: translate-in 2s cubic-bezier(0.39, 0.07, 0.15, 1) both 0.5s;
}
#credit div{
    margin: 30px;
}
#credit .space{
    margin-top: 60px;
}

nav{
    position: fixed;
    left: 50%;
    right: 50%;
    bottom: 50px;
    transform: translate(-50%, -50%);
    -webkit-transform: translate(-50%, -50%);
    -ms-transform: translate(-50%, -50%);
    text-align: center;
    width: 100px;
    height: 100px;
    background-color: #acdb00;
    border-radius: 50%;
    transition: background-color 0.3s;
}
nav a{
    position: relative;
    display: block;
    width: 100%;
    height: 100%;
    font-size: 3em;
    text-decoration: none;
    color: white;
    margin: 0;
    padding: 0;
    border-radius: 50%;
}
nav a i{
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translateY(-50%) translateX(-50%);
    -webkit-transform: translateY(-50%) translateX(-50%);
}
nav:hover{
    background-color: #f0f0f0;
}
@keyframes bg-animation{
    from{
        -webkit-clip-path: polygon(0 0,100% 0,100% 0,0 0);
        clip-path: polygon(0 0,100% 0,100% 0,0 0);
    }
    to{
        -webkit-clip-path: polygon(0 0,100% 0,100% 350px,0 250px);
        clip-path: polygon(0 0,100% 0,100% 350px,0 250px);
    }
}
@keyframes translate-in{
    from{
        transform: translateY(50px);
        opacity: 0;
    }
    to{
        transform: translateY(0%);
        opacity: 100%;
    }
}
@keyframes translate-in2{
    from{
        transform: translateY(-50px);
        opacity: 0;
    }
    to{
        transform: translateY(0%);
        opacity: 100%;
    }
}