.inner { padding:0 20px; } 
#container.main .mv .txt_box { width: 100%; text-align: center; } 
.main_introduce_1_img { float: initial; display: block; text-align: center; } 
.main_introduce_1_text { float: initial; text-align: left; width: 600px; margin: 0 auto; } 
.main_introduce_2_img { position: relative; left: 0; top: 0; width: 100%; text-align: center; } 
.main_introduce_2_img img { max-width: 625px; width:100%; } 
.main_introduce_2_text { float: initial; margin-right: 0; width: 600px; margin: 0 auto; } 

.main_content02 { padding-bottom: 0; }
.main_content03_bg h3 { text-align:center; } 
.main_content4 .main_title .next_prev { position: relative; width: 120px; font-size: 0; left: 0; bottom: 0; margin-top: 50px; margin-bottom:50px; } 
.main_content4 .main_slider { float:initial; width: 100%; margin:0 auto; }
.main_content4 .main_slide01 { text-align: center; }
.main_content4 .text_box { width: 100%; }

#videos {
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
}

#videos a {
    width: calc(50% - 10px);
    height: 100%;
    flex: initial;
}

#videos a:first-child {    
    width: 100%;
}